Checking radiator for overheating problem with 1956 Thunderbird

[zuburg]

I am trying to diagnose overheating problem with newly remanufactured 292 in a1956 Thunderbird. I took some infrared temperatures of various places to try and determine if new thermostat (I believe I used a 180 degree) and new water pump are working, as well as is the radiator restricted. Here are the temps:
225 Timing cover
216 Thermostat housing
198 Top radiator hose close to water pump
194 Top radiator hose close to radiator
220 Top radiator inlet tube
197 Water pump
174 Lower radiator hose
172 Lower radiator outlet tube
160 Heater hose from water pump
170 Heater hose from heater control valve

What do these temps indicate? The only thing that makes any sense is a restricted radiator, as everything else in the mix is new. I had the radiator cleaned out and pressure tested years ago, but while it sat in my garage waiting for the delayed new engine installed, mice found their way into the lower inlet tube bringing bird seed with them. I poured over 50 gallons of water through the radiator until I saw no more bird seeds, but I wonder if some could have gotten stuck in any tubing? Some of the seeds were shells from sunflower seeds. Is the tubing small enough that they could get stuck?

I also read after taking the initial temps that I should check temps on the upper, middle and lower part of the radiator looking for cold spots. It was 5-10 min. Before I read that but went ahead with taking the temps without starting the engine again. The temps got progressively less as I went from top to bottom. Is that typical? or should they be close to the same throughout?

[Dobie Gillis]

On a down flow radiator you should see a temperature drop from the top to the bottom, so it seems to be working. How well it's working is a horse of another color. Since the mice got in there and brought their buffet with them I think I'd have a radiator shop check it out and make a recommendation.

[KULTULZ]

I also read after taking the initial temps that I should check temps on the upper, middle and lower part of the radiator looking for cold spots.

If any cold spots are found in the core, it indicates blocked tubing at that point. Maybe it is safest to have the radiator flow tested and then roded if necessary.

Look through the upper tank radiator cap opening at the size of the tubing and you will realize it doesn't take much to cause blockage.

Is the car overheating? In traffic or highway?

Many factors in the BIRD COOLING SYSTEM design can cause overheating. It wasn't all that well designed.

[zuburg]

I wasn’t on the highway, but also not in traffic. I was driving in town with little traffic and 45mph for much of the time.

[Dobie Gillis]

In case it needs to be rodded out here's one way to do it:

https://www.youtube.com/watch?v=mcH-H9B1Rc8

[zuburg]

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Wow. Is this what radiator shops do as well?

[Dobie Gillis]

Essentially, yes. There are different methods. If you check YouTube there are several videos about it.

[dmsfrr]

Is the thermostat the type with the standard opening or an oversized one?
The version with the larger opening may allow better flow out of the engine into the top of the radiator. The side of the thermostat with the coiled spring faces into the intake manifold.

https://www.ctci.org/1957-thermostat/

https://www.classictbird.com/Thermos...uctinfo/8575C/

[KULTULZ]

The extension is threaded into the valve and can be removed by turning it counter clockwise. Once removed the NAPA # 6 thermostat can open fully. Removal of the extension does not effect the operation of the heater control valve.

Gil Baumgartner

That statement is not quite true. He should have added IMO.

[40cpe]

Your temperature drop of 48 degrees from the top (inlet) tube of the radiator to the bottom (outlet) indicates excellent cooling within the radiator. The even, steady drop and absence of cool spots top to bottom is consistent with good cooling. I've also read that the infrared thermometers don't read accurately on rubber, which I assume is the reason for the wide difference between the upper radiator hose and the upper inlet tube.

[zuburg]

Thanks, that’s the kind of info I was hoping for, before I start tearing into the radiator. Maybe I should check the thermostat first. Maybe it is stuck closed?

[40cpe]

Thinking of some possible causes on a newly built engine and install: Sometimes the thermostats are installed backwards. the spring/pellet end goes to the engine. You seems to have coolant flow, so that might not be your case. You could take it out to eliminate it as the problem. Being a newly built engine, it could be exhaust in the coolant if a head gasket didn't seal. There are kits to check for exhaust gasses in coolant if you don't find another cause. Also check for cooling fan installed backwards.

[zuburg]

Follow-up on overheating problem:
Replaced new water pump with new high output water pump.
Replaced thermostat with large opening thermostat (Gil Baumgartner)
Drove car in 75 degree outside temp for 15 min. in very light traffic going about 45 mph most of the time, and the temperature gauge was steady about at the red line in photo (appeared to be about the thickness of the needle past the center of the large white line on the gauge. Continued to drive another 15 min. in some heavier traffic including some long red lights and the temperature climbed to a little above where the photo shows, but never got to the end of the large white line on the gauge. I drove home as it started to move towards the end of the large white line for fear it would overheat and force me to pull over in traffic.

Does this appear normal as temperature gauges go during operation? Or should the temperature stay closer to the middle of the large white bar in these conditions?

If it appears my car is overheating in these conditions, there is a chance we installed a head gasket upside down on the drivers side as we pulled this head and reinstalled to fix another issue. Just wanted to try everything else before having to go to the trouble of pulling the head.

One other question about the radiator. I was looking at the overflow tube coming out of the side of the neck where the radiator cap goes and noticed it was loose and a small piece of plastic tubing was inserted into the overflow tube and inserted into the hole in the neck, more or less attaching the tube to the neck. Is this how it is supposed to be or was this some kind of hack by the previous owner?

[dmsfrr]

It seems quite normal to me. Especially since the old gauges can be inaccurate & tend to read high.
The handheld infrared temp gun will confirm the readings you're getting. 180* to 200* on the thermostat housing is normal. Photo 3
If it isn't spitting out coolant it isn't overheating. Coolant level should be an inch or so below the filler neck when cold, to allow for expansion.

When installing head gaskets one of them should look upside down compared to the other, it's the way they're made. The matching squared off corners of both gaskets should peek out from the upper front corner of the heads when they're installed correctly. Photo 1

A short metal tube should be soldered into the radiator filler neck, with a flexible tube on it, leading off to the bottom corner of the radiator (photo 2) or an overflow bottle.
.

[zuburg]

Thank you DMSFRR. You don’t know how relieved I am to now know my head gasket is on correctly. Thank you for that picture.

Regarding the overflow tube, are you saying a very short metal tube is soldered to the filler neck, and then a flexible tube (rubber hose) is attached to that and routed across the top and down the side of the radiator? My tube is metal across the top and down the side. The end of the tube is wider than the rest of the tube and looks like it could be soldered to the neck.

Should I solder the existing metal tube to the filler neck?

See photos.
Photo 1: metal tube pulled out of filler neck with plastic tube still inserted. Notice the expanded end of the metal tube.
Photo 2: the plastic tube pulled out of the end of the metal tube.
Photo 3: A view of the hole on the side of the filler tube.

[dmsfrr]

I wouldn't be concerned that it's a metal tube as compared to a rubber one...
But the top end should be soldered to the filler neck.

For whatever it's worth... on my '55 radiator the tube seems to also be soldered to this raised area of the top tank, apparently for additional stability.
.

[Late model]

Originally Posted by 40cpe

Your temperature drop of 48 degrees from the top (inlet) tube of the radiator to the bottom (outlet) indicates excellent cooling within the radiator. The even, steady drop and absence of cool spots top to bottom is consistent with good cooling. I've also read that the infrared thermometers don't read accurately on rubber, which I assume is the reason for the wide difference between the upper radiator hose and the upper inlet tube.

Your right about the problems with IR guns. This link pretty well explains them.
I was kind of wondering about the 48 degree drop. The normal radiator water temp drop is usually between 10-30 F. A large drop can indicate an obstructed radiator, the reduced flow receiving more than enough air causing the high temp differential. A low temp differential (10 degrees or lower) usually indicates low air flow. The radiator is not getting enough air for the conditions it's running in. In rare cases too high of water flow (no thermostat, over sped water pump etc.) can also cause a low temp drop. The water is passing through the radiator so fast there isn't time for good heat transfer.
To accurately diagnose overheating problems you need to know the radiator inlet and outlet water temps, the inlet and outlet cooling air temps, and the radiator flow.
That's an awful lot of work, and checking the obvious things first makes more sense, but at some point checking these things I just mentioned can help.
In this case if the drop is that high I would suspect that the mouse problem and the high temp drop are connected.
I would try to see if I could find a couple of thermocouples and an electronic
thermometer that read them and get a close check on the radiator drop. I use a couple of hose clamps to hold the thermocouples against the radiator necks just forward of the hoses and if the leads are long enough, carry the thermometer in the car.
Try and find a heating and air conditioning technician and see if they might be able to do a test for you.

https://www.fluke.com/en-us/learn/bl...ed-thermometer

Don

[Ford blue blood]

Do you really have an over heating issue? Are you loosing water? Have you tried just idling and watch the temp gauge? Will it blow water out sitting and idling? You will not hurt the engine if you let it sit and idle to see if it blows water. Just shut it off if that happens and wait for everything to cool off before you do anything else.

[zuburg]

Before I installed the high output water pump, it did overheat with the gauge going all the way to H while driving, and the engine starting to run rough. Radiator and hoses were very hot, and lots of pressure and steam in the radiator. I will try the idle test you suggest next. If coolant does blow out, will that be through the overflow tube or through the cap?

[Old Redneck]

My 56 T-Bird has a 292 bored out 40 Thousands. I just installed a new 4 core radiator, High output Water pump, Electric Fan and Air Condition plus a Over flow tank so I don't lose antifreeze. I am finishing up installing the Air Condition with the Help Dave Lyle. He sure know what to do from installing Air Conditioning in his 57 T-Bird. We are installing Insulation inside the floor completely so the inside will be cool when using the Air Conditioning. Yes also installed a Alternator 100 AMP. Lots of work. This T-Bird should not overheat now.

[55blacktie]

Ted Eaton (eatonbalancing.com/y-blocksforever.com) has drilled and tapped the thermostat housing for a temperature sending unit, the location of which provides a more accurate reading.

[JimNNN]

I personally would never trust a factory gauge from that era. I was convinced my '54 Y block ran a bit too warm for years until I bought an aftermarket mechanical gauge of decent quality. I checked it with boiling water before installation to verify accuracy. I then discovered it had likely been running too cool. I bought a new t-stat with a higher temp, and now it reads pretty much where it should.

And don't get me started about the factory oil pressure gauge on my '65 T-Bird that said my pressure was too low....

[zuburg]

Just finished another 40 min test drive with no overheating problems. I think this one is put to bed. Now I have to try and get a Fordomatic fluid leak sorted. It is leaking around the shift linkage. Trying transmission sealer additive first.

[Dobie Gillis]

Snake oil may reduce or seal your transmission leak temporarily but eventually it will start leaking again, and maybe worse than it is now. It works by swelling the seal which also softens it while also swelling and softening all the other seals in the transmission. Best to reseal it IMHO.

[rotorwrench]

The seals for the shift and TV control are small and deteriorate like any other type seal. They should be replaceable in the car but I don't have the later manual that would cover the later type medium case units so I can't confirm that.

I wouldn't put any sealing additives in one of the old FOM or COM transmissions. Stuff like that can affect the way the unit shifts and it's basically a band aid fix anyway. If it's just a little puddle then put a drip tray underneath to catch it until you can get a round tuit.

[55blacktie]

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C I buy "a round tuit" at Harbor Freight? If so, does it come with instructions?

[55blacktie]

Maybe the instructions "can" tell me how to type, too.

[Dobie Gillis]

Amazon has a pretty good selection of round tuit goods.

https://www.amazon.com/round-tuit/s?k=a+round+tuit

[Ford blue blood]

Originally Posted by zuburg

Just finished another 40 min test drive with no overheating problems. I think this one is put to bed. Now I have to try and get a Fordomatic fluid leak sorted. It is leaking around the shift linkage. Trying transmission sealer additive first.

Most excellent! What was the "fix"?

[zuburg]

I’m still fighting my overheating problem. I borrowed a coolant system pressure test kit from Autozone and pumped up the pressure through the fill neck. It identified several hoses leaking that didn’t leak coolant after driving (I assume because it never pressurized the system with the other leaks.

I tightened all the clamps and tested again, and I thought it held pressure, so I went for another test drive and it overheated again. When I got home coolant was spraying out pretty good from that short hose from the tube below the upper radiator hose and the water pump. I believe it was leaking from the side of the hose like the clamp cut through the hose. I have a piece of hose but will go to see if I can find better hose clamps (I thought the ones I had were really good ones).

Question: Should I be able to change that short hose without removing anything like the thermostat housing? I remember it was very difficult putting it on the first time as there was not enough room to bend the short hose to fit on both nipples. I put the hose on the thermostat housing before attaching the thermostat housing. Hoping to avoid that.

Oh, and is the hose 5/8” like the heater hoses?

[dmsfrr]

It's the same size as the heater hose. Remove the upper radiator hose from the thermostat housing to gain some room to work.

On these two parts check for corrosion & leaking of the small metal tubes for the bypass hose.

[KULTULZ]

I tightened all the clamps and tested again, and I thought it held pressure, so I went for another test drive and it overheated again. When I got home coolant was spraying out pretty good from that short hose from the tube below the upper radiator hose and the water pump. I believe it was leaking from the side of the hose like the clamp cut through the hose. I have a piece of hose but will go to see if I can find better hose clamps (I thought the ones I had were really good ones).

When you found the leaks and repaired, the system was able to maintain pressure (dictated by cap rated pressure). That pressure then found a weak spot (WP by-pass hose).

The pressure checker ... ... er TESTER, should also be able to test the pressure cap for it's ability to hold designated pressure. The rated system pressure (along with correct coolant) lowers the boiling point of the coolant.

How old are the cooling hoses? Do they need replacement? If you do need to remove the thermostat housing to replace the by-pass hose, now would be a good time to go to a wide-mouth thermostat (IMO).

OFFICIAL KULTULZ EDIT -

1955/ Used a 12-15 lb Cap.

Is the rating stamped on your cap?

[paul2748]

You say it is overheating again. What are the temperature figures ? Just because the bypass hose leaked does not mean it's overheating - it just mean you have a leak at pressure.


To get a new hose on the bypass, make it a little shorter that the distance between the mounting points of the nipples (make sure it's long enough so clamps work on the nipples). I have been successful in replacing the hose there, but it took some work . The alternative is to remove the nipple at the water pump, slide it in the hose (still a little shorter as noted above and with a new gasket and some rtv reconnect the nipple to the pump, then install the clamps. Easier to do this than remove the stat housing in my opinion.


The nipples on the by pass hose is one of those spots that I think the engineers went south on because they did not have a raised section on the ends to help seal.

Originally Posted by zuburg

I tightened all the clamps and tested again, and I thought it held pressure, so I went for another test drive and it overheated again. When I got home coolant was spraying out pretty good from that short hose from the tube below the upper radiator hose and the water pump. I believe it was leaking from the side of the hose like the clamp cut through the hose. I have a piece of hose but will go to see if I can find better hose clamps (I thought the ones I had were really good ones).

Question: Should I be able to change that short hose without removing anything like the thermostat housing? I remember it was very difficult putting it on the first time as there was not enough room to bend the short hose to fit on both nipples. I put the hose on the thermostat housing before attaching the thermostat housing. Hoping to avoid that.

Oh, and is the hose 5/8” like the heater hoses?

[55blacktie]

Here is a quote from Ted Eaton: "I have not had any issues with the extension tube interfering with the thermostat. But I typically just use auto store bought thermostats. I have heard of interference issues but have yet to see it with the thermostats that I use. On the flip side of all of that, I do not see a problem in removing or shortening the extension tube if it looks like there is going to be an interference issue."

[KULTULZ]

Originally Posted by 55blacktie

Here is a quote from Ted Eaton: "I have not had any issues with the extension tube interfering with the thermostat. But I typically just use auto store bought thermostats.

I have heard of interference issues but have yet to see it with the thermostats that I use. On the flip side of all of that, I do not see a problem in removing or shortening the extension tube if it looks like there is going to be an interference issue."

I think Ted is referring to the possible interference of the heater control valve pickup with a wide mouth thermostat and that being limited to the ECZ-B intake as the carb pad was moved forward.

The reason for the deep pickup tube on the valve is so that it draws coolant from the bottom of the coolant runner as it will likely contain less air bubbles (coolant aeration) than in the top (in an open system). It needs that deep pickup tube unless possibly you are running a closed system with an recovery bottle.

[blucar]

Reading through the majority of the comments about overheating I did not see any mention about the baffle plate between the water pump and the timing case cover.
The Birds had a baffle plate, well maybe I should mention that my '56 292 T-bird special and '57 312 had the water pump baffle's. Over time the baffle's rusted out, replacements were very hard to find.
When I trained as a mechanic in the early '50's it was mandatory that all thermostats were tested in a pan oi boiling water prior to installation.
I am a firm believer in coolant recover systems. I have utilized them on every vehicle I have owed since the mid seventies.
I had my '57 Bird for 45 years, still have the '56 Bird, second owner since 1980..

[delco1946]

Didn't see anyone else mention it, but as memory serve practice was in the day to use a 160 thermo in the summer and a 180 in the winter (in places like the dakotas!). Pretty sure my 292 also has a 160 degree thermo.

[KULTULZ]

Originally Posted by blucar

Reading through the majority of the comments about overheating I did not see any mention about the baffle plate between the water pump and the timing case cover.

You are describing the actual WP spacer (8A510) as used on the BIRD exclusively?

[blucar]

Originally Posted by delco1946

Didn't see anyone else mention it, but as memory serve practice was in the day to use a 160 thermo in the summer and a 180 in the winter (in places like the dakotas!). Pretty sure my 292 also has a 160 degree thermo.

I don't recall seeing any printed difference between summer/winter stats. The factory spec is 180 on the majority of pre-emmission engines. Most people do not understand just what the importance is to maintain the correct operating temp of an engine.. Many myth's and old habits prevail.
I am not to sure just what the purpose of the baffle plate between the water pump and the timing case is, I have never seem one on a truck Y block. I don't think it is a spacer plate because the plate is only about 16/18 gauge which is less than 1/16 of an inch.

[KULTULZ]

There were generally two differently rated thermostats in this period, one rated for water based coolant (160) and another for alchohol or permanent coolant (172). Pressure caps were rated @ #7 and #14 as the system pressure has much to do with the cooling system boiling point.

The alcohol ... ... based coolant was to be changed to water and a can of water pump lubricant/anti-rust in spring. Then again changes to alcohol based coolant in the fall. Usually the thermostat was changed to 160 for summer and 172 for winter.

When permanent coolant was introduced, this all changed.

[cokefirst]

I have owned 7 little thunderbirds and it has been my experience that the normal operating temperature on the factory gauge is at the end of the red line closest to hot. Purchase an infrared temperature checker (you can buy and inexpensive one from Harbor Freight) and check the actual operating temperature.
With a 7 # cap at sea level, the boiling point of water is about 228 degrees. So if your temperature at the top of the radiator is less than that (say 218 degrees) you are good. The 180 thermostat is supposed to keep the coolant at the minimum of 180 degrees. Once it reaches that temperature, the thermostat opens and should be fully open at 200 degrees. Remember that what we call a temperature gauge is really an indicator since it is not calibrated with actual numbers.

[KULTULZ]

What happens if and when the coolant temp exceeds the boiling point, the cap (if operating properly and the correct pressure rating) will open and expel coolant to somewhat normalize internal system pressure. The trouble is as the coolant cools, that open cap will draw outside air and that is where your air pockets and aerated coolant comes into play.

It needs a recovery system.

EDIT -

The above is also true when the engine is shutdown and heat soak heats the coolant to a point where it forces the cap pressure release to open and burps coolant all over you nice cobblestone driveway. As the engine cools, the coolant contracts drawing outside air into the system before the cap relief fully closes. You then have air pockets in the cooling system which may cause further overheating problem(s).

[Ford blue blood]

I live by a simple rule....If it ain't losing water it ain't over heating....engine will be fine as long as it has coolant in it.

Got caught in traffic in Memphis on a 100 plus day, temp went up to 220, turned the air off much to the wifes ire, finally got back on the road and all was well. That was some 60K miles ago on that ol 351C in my 36.

[blucar]

I generally run aftermarket improved fan blades on my vintage vehicles, have a couple old cars with AC, electric fan with shroud or a thermal clutch type.
Many years ago I had a '65 Chevy C20 camper special, V/8 AT with a large RV camper on it. The first two years I had THE '65 I had nothing but trouble with it running hot, gauge almost maxed out.
Tried everything to cool the engine down, larger radiator, HD fan assembly, larger trans cooler coolant recovery system. I finally put a mechanical temp gauge on the engine, leaving the stock gauge in place. The mechanical gauge never got above 200/215, 15 lb cap and 50/50 coolant put the boiling point to about 250, the engine did not boil over and the coolant recovery system did it's job.
Going over the Donner Pass in August 1970 towards Reno the trans over-heated and burped fluid from the fill tube onto a hot manifold, lots of smoke, thought the engine was on fire, then noted the smoke was intermediate, just short puffs, pulled over as soon as I could, leaving the engine running I grabbed my fire extinguisher and slowly opened the hood. Seeing what the problem was I let the engine idle for awhile to lower the temp then continued on to Reno.
I went to the GMC agency in Reno to have the truck checked over, other than the trans fluid being a little low everything seemed to be fine. Myself and a mechanic took the truck for a test drive, he suggested that I run the trans, a TH400 a little low on the dip stick to avoid oil boil over from over heating.
The mechanic then asked me what year was the truck, I told him '65, he replied that GM had a lot of trouble with the '65 C10-20's running hot, there was a factory recall on the trucks, their shop saw a lot of them coming out of California with reputed overheating problems. The problem was a faulty gauge, the fix was a factory supplied resister in the wire to the gauge.
Moral to the story, it is very common to make a minor issue into a big deal, a mole hill becomes a mountain.

[zuburg]

It was over 240 and rising. At that point it was bubbling coolant at weak hose points. When I checked the bypass hose, I notice the nipple on the thermostat housing was corroded and Deformed so I bought a new housing and bypass nipple while I was at it. I just finished putting it all back together earlier today. I did use the technique you described of putting the bypass nipple in the hose, connecting the hose to the housing first, then just dropping the bypass nipple in place. Went nice and smooth for a change.

I plan to add coolant tomorrow and doing another pressure check to make sure everthing is tight. Then a test drive on a 94 degree day.

[dmsfrr]

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Originally Posted by zuburg

It was over 240 and rising.....

Can you see coolant moving thru the radiator?
Remove the radiator cap when the engine is cool or at least not too hot. Then let it run (with the garage door open) until the engine gets up to operating temperature and look into the top of the radiator. You should be able to see the coolant circulating.

[zuburg]

I have tried that to confirm it is circulating, but I have heard it won’t circulate if under 800 RPM. I wonder if that is why I can’t tell if it is circulating. Next time I will get my wife or a friend to help by increasing the RPM. I have taken temperatures of the thermostat housing, upper/lower radiator hose and 3 places on the radiator fins (top, middle and lower). The temps on the radiator fins progressively got cooler from top to bottom. I thought that indicated it was circulating?

[KULTULZ]

Originally Posted by zuburg

I have tried that to confirm it is circulating, but I have heard it won’t circulate if under 800 RPM. I wonder if that is why I can’t tell if it is circulating. Next time I will get my wife or a friend to help by increasing the RPM. I have taken temperatures of the thermostat housing, upper/lower radiator hose and 3 places on the radiator fins (top, middle and lower).

If you look into the upper tank with the cap off (be careful here) and the thermostat has opened, if you don't see coolant movement, you need to increase the speed of the water pump, i.e. a smaller dia water pump pulley. Just reach over and operate the throttle linkage by hand. If you see flow at a higher RPM, you will likely need a smaller WP pulley. You have a 4-blade fan?

The temps on the radiator fins progressively got cooler from top to bottom. I thought that indicated it was circulating?

That indicates it is cooling. It does not indicate fluid flow rate which is going to dictate rate of cooling..

This is one problem with BIRDS, the other being a bad pump and/or WP spacer (8A510) volute and/or timing cover volute.

How long has it been since a complete cooling system service, hose/thermostat and coolant replacement?

1st EDIT -

Here is a basic tutorial - https://www.ctci.org/gilsgarage/1955...d-overheating/

Your IGN SYS is LOAD-O-MATIC and if the ignition advance is inoperative, will definitely cause over heating (1955/56 BIRD).

2nd EDIT -

https://thunderbird.us/

[55blacktie]

The cheap, infrared temperature readers aren't particularly accurate; my HF gun can be off by several degrees.

[zuburg]

I’ve just recently rebuilt this car. Remanufactured engine, all new hoses and belts, new large opening thermostat, new coolant, and even installed the special high flow water pump with the two impellers.

I do have the original 4 blade fan and original water pump spacer. I do know plan to increase the RPMs on my next test to confirm the coolant is circulating. I have read about the smaller pulley, that might be next.

Will it only overheat on days with very high temperatures like 85 degrees or higher?

[Late model]

Zuburg,
After reading these posts again I would like to circle back to the original post. I still see two things in there strongly indicate a radiator problem.
1. Mice made a restaurant out of the radiator while it was sitting for a long time.
2. When checking the radiator temps with a temp gun, if the readings were accurate, the difference between the inlet and outlet temps was 48F. This much higher than the usual 10 to 15F in a typical radiator. The link below has some great info on cooling system operation, especially in the first two pages.
https://www.enginebasics.com/Engine%...ing%20Pg3.html
Another concern is which way did the radiator get flushed, from inlet to outlet, or outlet to inlet. I assume inlet to outlet so as to drive the out the mouse dinner out, rather than in.
Because low coolant velocity through the system can also cause high temp drop you need to make sure you have some coolant movement at idle. If you do, then I think the next step is to verify the temp drop with a couple of thermocouples and an electronic thermometer. If it is actually that high, pull the radiator for rodding out or high pressure washing.
Don

[zuburg]

I was hoping to not have to drain all of the new coolant and pull the radiator. I’ll finish wrapping up my latest work and do another test and take temps with an IR thermometer & get some data to help decide.

I did flush the radiator from top to bottom. I kept pouring water through until no sign of bird seeds which was over 25 gallon jugs of water.

I heard the early birds did not circulate coolant under 800 RPMs (idle). Is that also the case with the special high flow water pump that has two impellers?

[dmsfrr]

Originally Posted by zuburg

....
I heard the early birds did not circulate coolant under 800 RPMs (idle). Is that also the case with the special high flow water pump that has two impellers?

Coolant flow at idle isn't quite that bad but it is less than half of the flow at 1500 RPM.
See this link...

https://www.classictbird.com/pdf/H2O...st-results.pdf
Please excuse the fact that this linked page is nearly 20 years old. The water pump shown was a diy example that was quickly replaced with a much better looking version.

I find myself agreeing with Late model, your initial temperature readings from post #1 could easily indicate poor coolant flow.

Originally Posted by blucar

Reading through the majority of the comments about overheating I did not see any mention about the baffle plate between the water pump and the timing case cover...

The baffle plate is shown and discussed at the link above.
.

[KULTULZ]

Originally Posted by zuburg

I did flush the radiator from top to bottom. I kept pouring water through until no sign of bird seeds which was over 25 gallon jugs of water.

That's not flushing, that's rinsing. If the RAD was (is) that bad, it needs to be tanked, pressure flushed and then flow tested.

The flow test will determine if rodding out (or a new radiator is necessary).

I heard the early birds did not circulate coolant under 800 RPMs (idle). Is that also the case with the special high flow water pump that has two impellers?

All year BIRDS had cooling problems. Measure the DIA of you WP pulley. Your BIRD came (assembled) with a 3- or 4-blade fan?

EXACTLY which pump did you buy and install?

EDIT -

Originally Posted by paul2748

CASCO's pump does not eliminate the spacer/usage. It has longer impellers that reach back into the spacer to move water.

Incorrect statement removed from text -

http://Was it one of CASCO's new cas... spacer usage?

CASCO 8501HO - It is used with the spacer ...

[KULTULZ]

- Repairing a Radiator by Rodding or Recoring -

CLICK HERE - https://www.roundforge.com/articles/...g-or-recoring/

[paul2748]

CASCO's pump does not eliminate the spacer/usage. It has longer impellers that reach back into the spacer to move water.

Originally Posted by KULTULZ

T
EXACTLY which pump did you buy and install? Was it one of CASCO's new castings that eliminates the spacer usage?

[dmsfrr]

Originally Posted by KULTULZ

... Your IGN SYS is LOAD-O-MATIC and if the ignition advance is inoperative, will definitely cause over heating (1955/56 BIRD) ...

Photo example of a Loadomatic distributor, used on Y-blocks from '54 thru the '56 model year.
Four pins with two springs.
If the plate the points & condenser are mounted on is stuck or does not move with vacuum applied, the ignition timing is not advancing. This will make the engine run hot.

https://www.ctci.org/gilsgarage/crac...aust-manifold/
.

[KULTULZ]

Originally Posted by paul2748

CASCO's pump does not eliminate the spacer/usage. It has longer impellers that reach back into the spacer to move water.

My mistake and stand corrected.

My reading comprehension seems to be lacking ...

[KULTULZ]

Originally Posted by zuburg

one other question about the radiator. I was looking at the overflow tube coming out of the side of the neck where the radiator cap goes and noticed it was loose and a small piece of plastic tubing was inserted into the overflow tube and inserted into the hole in the neck, more or less attaching the tube to the neck. Is this how it is supposed to be or was this some kind of hack by the previous owner?

Overflow Tube - CASCO 8005b

[zuburg]

What if you have a 13 # cap, which is what I have. That was supposedly the right one for this car.

[zuburg]

Is there an easy way to determine if the distributor is working correctly? It seems to run well at idle and while driving.

[paul2748]

As far as advance, put a timing light on and run up the engine speed. You should see the advance.

Originally Posted by zuburg

Is there an easy way to determine if the distributor is working correctly? It seems to run well at idle and while driving.

[KULTULZ]

Originally Posted by zuburg

What if you have a 13 # cap, which is what I have. That was supposedly the right one for this car.

You're Good!

[paul2748]

I believe that was stock. On old systems, especially an old radiator, a lower rating is advised, around 7 lbs. The higher the pressure rating, the higher the boiling point of the coolant. If your radiator is in good shape, the 13 s/b ok

Originally Posted by zuburg

What if you have a 13 # cap, which is what I have. That was supposedly the right one for this car.

[cokefirst]

Originally Posted by 55blacktie

The cheap, infrared temperature readers aren't particularly accurate; my HF gun can be off by several degrees.

You could be correct, My son has a Fluke one and I have the cheapo Harbor Freight one. They are withing 5 degrees of each other, so maybe I am just lucky.

[zuburg]

Sponsored Links (Register now to hide all advertisements)

Well, hopefully, the cheap one will be off 5 degrees all the time, so the temperature differences will be relatively accurate?

[paul2748]

You can overheat regardless of the outside temperature if there is a problem with the cooling system. Hot weather only makes it happen sooner.


In a good system, overheating should not occur.


Be sure the head gaskets are installed correctly - the square corner should be in the front and on top. Something some rebuilders do not know.

Originally Posted by zuburg

Will it only overheat on days with very high temperatures like 85 degrees or higher?

[zuburg]

Thanks. I finally have the cooling system holding pressure. The head gaskets are installed correctly with the square corners on the front. My next step is to ensure I don’t have any air pockets in the system, and if that doesn’t help, move to cleaning out or replacing the radiator. It may have some partial blockages.

[KULTULZ]

- THIS THREAD WAS CONTINUED HERE -

- MAXIMUM ACCEPTABLE COOLANT TEMP 292 FYB -

https://www.fordbarn.com/forum/showthread.php?t=316470

- COOLANT RECOVERY SYSTEMS -

https://www.fordbarn.com/forum/showt...=1#post2154741

[zuburg]

I thought some of you might get a kick out of the thermostat housing I replaced to solve a coolant leak. Me thinks me tightened the hose clamp a little too much on an old corroded tube. That was never going to stop leaking.

[KULTULZ]

Originally Posted by zuburg

Me thinks me tightened the hose clamp a little too much on an old corroded tube. That was never going to stop leaking.

Now that is gnarly but shows what else in the system may be corroded badly. One reason I hate worm clamps as other than appearance (not correct - gnarly) is that a big fella can put a lot of torque on one.

[paul2748]

You can new tubes for that

[KULTULZ]

Is the original cast iron or aluminum?

[dmsfrr]

Originally Posted by KULTULZ

Is the original cast iron or aluminum?

The main housing is cast iron and the original small tube is usually steel.

[KULTULZ]

Originally Posted by dmsfrr

The main housing is cast iron and the original small tube is usually steel.

THANX! for that.

I guess the repros are alum? I have seen different older styles with some having the by-pass as a part of the casting?

BTW -

That one is pretty gnarly also ...

[KULTULZ]

Originally Posted by zuburg

I thought some of you might get a kick out of the thermostat housing I replaced to solve a coolant leak. Me thinks me tightened the hose clamp a little too much on an old corroded tube. That was never going to stop leaking.

What shape is the tube at the WP?

[paul2748]

All the repros I've seen were cast iron.
And the water pump nipple also is available repro.

Originally Posted by KULTULZ

THANX! for that.

I guess the repros are alum? I have seen different older styles with some having the by-pass as a part of the casting?

BTW -

That one is pretty gnarly also ...

[dmsfrr]

Originally Posted by KULTULZ

. . .
BTW -
That one is pretty gnarly also ...

It's on my shelf as a leftover 'if you're desperate' spare part. The surface for the upper hose is a bit rougher looking than in the photo. It might work ok for a while with some JB Weld used for filler ???
.

[55blacktie]

As far as I know, only Mummert (ford-y-block-com) has an aluminum thermostat housing; it matches his aluminum intake manifold. Any Tbird supplier will have an original-type, cast-iron thermostat housing. The part # is 8592, which should cost about $50. Before you spend $50 + shipping, you might check with your local parts stores or Rock Auto.

[cokefirst]

If that is an original thermostat housing, you may want to fix it. You can remove and press in a new pipe. The replacement units do not have the casting identification of the OE part. I have fixed several of these for my cars.

[paul2748]

Looks like he's gone awol on us. No acknowledgements of anything

[zuburg]

I ended up buying both the housing and water pump nipple even though my old nipple was in good shape. I figured while I’m going through all this trouble, might as well use new parts. My car is just a driver, not a show car or numbers matching actual restoration.

All the above didn’t seem to fix the problem so I bought a replacement aluminum radiator. The new radiator came with a 16# cap. Is that OK to use or should I use a 13# cap I recently bought?

[KULTULZ]

The new radiator came with a 16# cap. Is that OK to use or should I use a 13# cap I recently bought?

- IMO -

I would use the 13# as you do not want to put too much pressure on things like the heater core and/or core plugs unless you are sure of their condition.

[KULTULZ]

Re-reading through this thread -

I borrowed a coolant system pressure test kit from Autozone and pumped up the pressure through the fill neck.

It identified several hoses leaking that didn’t leak coolant after driving (I assume because it never pressurized the system with the other leaks.

The pressure cap needs to be pressure tested also. It may not be holding the rated pressure

Originally Posted by blucar

I am not to sure just what the purpose of the baffle plate between the water pump and the timing case is, I have never seem one on a truck Y block. I don't think it is a spacer plate because the plate is only about 16/18 gauge which is less than 1/16 of an inch.

What period car did you see this on? It was a thin metal baffle plate? Did you see it on more than one BIRD application?

[KULTULZ]

- CASCO BIRD FYB HO WATER PUMP -

Detailed Description

Comes with 3 gaskets in a cardboard fold-over for protection. Do not discard as packing material.

Machined and assembled in USA

Work on non-Tbird engines? No - The pump only fits on Thunderbird engines. They can be identified by the 1" or so spacer that is situated between the water pump and the timing chain cover. It is the extra room created by the spacer that this pump exploits with extra fins on the back of the water pump impeller.

Knowledge Base

Install Directions

SOURCE - https://www.classictbird.com/Water-P...ctinfo/8501HO/

So now that I have received my education on this pump ... ..., it still uses the OEM WP SPACER 8A506 (BIRD UNIQUE) which is defective in design (along with possible poor casting of the volute in the timing cover), the over-heating problem is most likely still there.

It needs (IMO) to be used with the re-designed WP SPACER (PARAGON) and the timing cover inspected for poor casting - https://thunderbird.us/

[KULTULZ]

Sponsored Links (Register now to hide all advertisements)

- FlowKooler - The Leaders in Hi Flow Water Pumps -

FlowKooler water pumps prevent engine overheating. Each impeller is designed to generate higher flow rates and increase system pressure. Increasing coolant flow rate through the block reduces the cycle time between the engine and the radiator providing more opportunity for heat exchange. When flow rate is maximized, the higher flow rates raise engine block pressure to prevent the formation of steam pockets in the water jacket and the vapor barrier that can cause hot spots on cylinder walls.

If you are interested in a rebuild you are probably (A) restoring a numbers-matching car or (B) cannot find a new pump anywhere and either want a conventional pump or have experienced the benefits of hi flow. We have been helping restorers for 40 years in the construction of our radiators so it was an easy decision to use our hi flow impellers designs for numbers-matching cars and unavailable castings.

There are 3 scenarios we commonly see:

A. The casting volute, diameter, depth, angle and rotational direction match an existing pump impeller

B. The casting volute, diameter, depth, angle and rotational direction is close to an existing pump impeller but requires some modification

C. Nothing matches an existing impeller and we have to design from scratch

Contact us with your make, model and production year to purchase an impeller.

SOURCE - https://flowkoolerwaterpumps.com/

Here is your out if you want to retain the OEM WP w correct CASTING ID and DATE CODES.

The site says just the impeller is available and this along with a quality rebuild should cool the car down and retain originality (IMO).

They need to be contacted to see if the improved impeller fits PASS CAR and/or BIRD WP.

- HI-FLO Balanced Sleeve Thermostat

- https://flowkoolerwaterpumps.com/col...ns/thermostats

[KULTULZ]

Once you have a certified rebuildable block, the next step is to clean out the rust deposits in the water jacket. This step cannot be overemphasized! Occasionally these deposits are so solid that they must be chiseled out (Especially around the #4 and #8 cylinders). In some cases the rust affects the cylinder wall thickness and causes mysterious overheating problems. Rust deposits are the major cause of overheating problems in an otherwise good engine. So be very sure there are no residual rust deposits in the block after cleaning.

SOURCE - https://www.ctci.org/rebuilding-your...-block-engine/

[KULTULZ]

- IMPROVING FAN SHROUD DESIGN -

Now this gentleman has a GOD given talent -

https://www.youtube.com/watch?v=T4LslyotK44

Improved lower shrouds are available.

[zuburg]

Yes, I watched this video last week. He is indeed talented and has the tools and equipment to pull it off in a reasonable time.

[KULTULZ]

The reason for the posting was to demonstrate the need for a full shroud.

Full bottom sections are available at BIRD SUPPLIERS.

How is your BIRD doing?

[KULTULZ]

Is any of this discussion helping/informing anyone? I see 4200 hits but few comments or questions.

It seems any BIRD board you go to has endless questions regarding overheating and all of the available information was never brought together.

[KULTULZ]

- ... guess not ... -

[dmsfrr]

Originally Posted by KULTULZ

...
It seems any BIRD board you go to has endless questions regarding overheating and all of the available information was never brought together.

This linked page covers much of the overheating problems but folks may not be aware of it.

https://www.ctci.org/1955-56-57-thun...d-overheating/

[40cpe]

Originally Posted by KULTULZ

Is any of this discussion helping/informing anyone? I see 4200 hits but few comments or questions.

I would guess that the ratio of early Bird owners on this forum is low to be the reason for the lower interest. I had a '55 in the middle/late '60s, went on my honeymoon in it. It gets hot in the summer here. I remember watching the temp gauge while in traffic, don't remember it ever boiling though. I also remember the lack of air circulation in the cabin.

[paul2748]

Lack of air circulation in the 55's was the reason they put the side vents on the 56's and 57's.

Originally Posted by 40cpe

I would guess that the ratio of early Bird owners on this forum is low to be the reason for the lower interest. I had a '55 in the middle/late '60s, went on my honeymoon in it. It gets hot in the summer here. I remember watching the temp gauge while in traffic, don't remember it ever boiling though. I also remember the lack of air circulation in the cabin.

[Patrick brophy]

I have read every word,and I have also taken some good advise.
I installed one of the paragon water pump spacers, and I also went the lower full fan shroud route.
I really cannot comment on the performance, as I have not yet got the car road worthy. Soon I hope.

[KULTULZ]

Originally Posted by Patrick brophy

I have read every word,and I have also taken some good advise.
I installed one of the paragon water pump spacers, and I also went the lower full fan shroud route.

I really cannot comment on the performance, as I have not yet got the car road worthy. Soon I hope.

THANX!

I thought I was preaching to the choir there at the end.

It seems to draw interest as there are 4000 hits. I was trying to bring out more detailed info that was loosely scattered on the net.

There is more to discuss. Just wondering if I was farting in a windstorm ...

[KULTULZ]

Originally Posted by dmsfrr

This linked page covers much of the overheating problems but folks may not be aware of it.

https://www.ctci.org/1955-56-57-thun...d-overheating/

I don't have their manual but I would like to see how far involved with this subject they go -

11- See page 386 & 387 of the restoration manual on how to relieve hot spots between 2 & 3 cylinders on the right bank and 6 & 7 cylinders on the left bank of the engine block.

[dmsfrr]

11- See page 386 & 387 of the restoration manual on how to relieve hot spots between 2 & 3 cylinders on the right bank and 6 & 7 cylinders on the left bank of the engine block.

Originally Posted by KULTULZ

I don't have their manual but I would like to see how far involved with this subject they go -

It's a brief paragraph & description of how to use these two pre-cut holes in the head gaskets as a template to mark the block & heads for a pair of added holes and the drilling process: start with smaller bits and work up to the final size of...
11/64 for the upper hole and 1/4 for the lower hole.

[55blacktie]

There is a lot of controversy regarding whether or not to add the steam holes. You'll find an in-depth discussion on y-blocksforever.com. I think the consensus is don't plug existing holes, but don't add holes. Also, there could be sealing issues using gaskets with holes if your engine doesn't have the holes.

[dmsfrr]

Originally Posted by 55blacktie

There is a lot of controversy regarding whether or not to add the steam holes. You'll find an in-depth discussion on y-blocksforever.com. I think the consensus is don't plug existing holes, but don't add holes. Also, there could be sealing issues using gaskets with holes if your engine doesn't have the holes.

The owner of the old-school machine shop that rebuilt my two Y-blocks recommended leaving the blocks & heads 'as-is', without additional holes.
.

[KULTULZ]

Originally Posted by dmsfrr

It's a brief paragraph & description of how to use these two pre-cut holes in the head gaskets as a template to mark the block & heads for a pair of added holes and the drilling process: start with smaller bits and work up to the final size of...

11/64 for the upper hole and 1/4 for the lower hole.

THANK YOU! for that info ...

[KULTULZ]

Originally Posted by 55blacktie

There is a lot of controversy regarding whether or not to add the steam holes. You'll find an in-depth discussion on y-blocksforever.com. I think the consensus is don't plug existing holes, but don't add holes. Also, there could be sealing issues using gaskets with holes if your engine doesn't have the holes.

!!! VERY IMPORTANT POINT !!!

As hot as some of these BIRDS get, I wonder why there are not more failures.

Here is the info thread from y-blocksforever -

http://forums.y-blocksforever.com/To...ate=1#bm161912

[KULTULZ]

- INFO BROUGHT OVER FROM y-blocks.forever -

SOURCE - http://forums.y-blocksforever.com/Po...arentID=162051

[paul2748]

Those pumps have been superceeded by a new design.

Originally Posted by KULTULZ

- INFO BROUGHT OVER FROM y-blocks.forever -

SOURCE - http://forums.y-blocksforever.com/Po...arentID=162051

[KULTULZ]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by paul2748

Those pumps have been superceeded by a new design.

They are still advertising the impeller modification -

https://www.classictbird.com/Service...tinfo/8501HOY/

This service includes installing our three blade modification on the back of the original impeller.

[KULTULZ]

Another excerpt from !!! - Y-BlocksForvever - !!!

Sand/dirt build up in the blocks is common but I don't think it's casting sand. This is not just a Y-Block nuance but all engines in general. I call it ‘Mud’ and it gets packed in there very tightly or hard. Most older engines in the shop for rebuild have it and it is attributed to using tap water for the cooling system. While distilled water is recommended for cooling system use, that is not a standard practice. That ‘Mud’ typically accumulates at the back of the block around the rear cylinders where the water flow is slowest and then has to transition up to the cylinder heads to make its way forward to exit the engine. That transition upwards has the solids in the coolant dropping out at that point. Because it accumulates mostly around the rear cylinders, it does add to abnormal heating of the engine at the rear of the block. Not thoroughly cleaning the block during the rebuilding process has that new engine running hotter than normal than it should.

Removing it requires some serious cleaning of which manually breaking it up and digging it out is required before actually doing a wash on the block. Using a caustic tank or wash initially is not enough to remove that sludge without some initial digging first. The really bad blocks will have a quart or more of that sludge in each side.

- TED EATON

Read thru the entire thread here - http://forums.y-blocksforever.com/Topic161202-1.aspx

EDIT - ADD'L INFO

If you folks install aluminum radiators, aluminum timing covers, aluminum heads, or aluminum intake manifolds, you should consider using anti-freeze that is designed for aluminum parts. If you don't you will have a short lived radiator, or corroded aluminum engine part. Joe-JDC

ADDENDUM- (Fr. For Edit)

Originally Posted by dmsfrr

This linked page covers much of the overheating problems but folks may not be aware of it.

https://www.ctci.org/1955-56-57-thun...d-overheating/

11- See page 386 & 387 of the restoration manual on how to relieve hot spots between 2 & 3 cylinders on the right bank and 6 & 7 cylinders on the left bank of the engine block.

It's a brief paragraph & description of how to use these two pre-cut holes in the head gaskets as a template to mark the block & heads for a pair of added holes and the drilling process: start with smaller bits and work up to the final size of... 11/64 for the upper hole and 1/4 for the lower hole.

There is a lot to consider and figure to solve the problem(s) in one fell swoop.

[KULTULZ]

I am not to sure just what the purpose of the baffle plate between the water pump and the timing case is, I have never seem one on a truck Y block. I don't think it is a spacer plate because the plate is only about 16/18 gauge which is less than 1/16 of an inch.

You are describing the actual WP spacer (8A510) as used on the BIRD exclusively?

... chirp ... chirp ... chirp ...

https://www.classictbird.com/pdf/H2O...st-results.pdf

The baffle plate is shown and discussed at the link above.
.

If what is being discussed as a baffle plate is as shown below, it is ineffective and not needed -

[KULTULZ]

Regarding the overflow tube, are you saying a very short metal tube is soldered to the filler neck, and then a flexible tube (rubber hose) is attached to that and routed across the top and down the side of the radiator? My tube is metal across the top and down the side. The end of the tube is wider than the rest of the tube and looks like it could be soldered to the neck.

The overflow tube being metal is for safety. If you open the cap (1st safety position) while checking coolant level (while hot), the coolant will scald your fingers instead of being discharged to the ground.

Reproduction tubes are available.

*****

Just because the bypass hose leaked does not mean it's overheating - it just mean you have a leak at pressure.

But it will overheat @ some point, if not overheating when the leak is discovered. You have a loss of coolant volume and loss of system pressure which will lower the boiling point of the coolant still left in the system.

[paul2748]

There is no problem running a rubber hose as the overflow tube. My 48 with a 302 has been running one for 40 years.



My 56 Bird has the overflow tube on the right (passenger side) with what looks like a stock radiator.

[KULTULZ]

Originally Posted by paul2748

There is no problem running a rubber hose as the overflow tube.

Paul, you forgot to add IMO.

IMO, one would want to keep (I would hope) a BIRD as original as possible. We aren't talking RESTO-MOD here.

If someone just wants a cheap fix, AUTOZONE is the place to be to ask questions.

[paul2748]

And we are not talking a Concours car either.

Originally Posted by KULTULZ

Paul, you forgot to add IMO.

IMO, one would want to keep (I would hope) a BIRD as original as possible. We aren't talking RESTO-MOD here.

If someone just wants a cheap fix, AUTOZONE is the place to be to ask questions.

[KULTULZ]

There are certain things you do to an automobile and certain things you don't. I don't think he is using the car as an everyday beater.

Can you guess as to a person's ability when he opens the hood and all that is seen is duct tape and baling wire?

[paul2748]

I hardly think that a rubber overflow hose is in the same league with duct tape and bailing wire.. Of course, everything had to be done correctly.


Just to let you know, I have a 56 Bird - and I take special pains to make sure anything I do is done correctly, safely and neatly. Same with my other two cars. And I wouldn't suggest to any one else to do something different.


And I resent the hint/suggestion that I would advise someone to do a hack job on a car (or anything else)

Originally Posted by KULTULZ

There are certain things you do to an automobile and certain things you don't. I don't think he is using the car as an everyday beater.

Can you guess as to a person's ability when he opens the hood and all that is seen is duct tape and baling wire?