How hot can you really run a flathead safely?

[G.M.]

Who cares about how hot it needs to get to boil the water out?? It should never get to the temperature of 212. If it does there is a problem that needs to be fixed. Again I say look at the temperature gauge in ANY old Ford and you will find what temperature normal and hot is. G.M.

[Old Henry]

Originally Posted by G.M.

Who cares about how hot it needs to get to boil the water out??G.M.

Me. And many others, since below that temperature there's no problem. Over that temperature you got problems.

212 deg. is only the limit at sea level with no pressure radiator cap. Any pressure cap will raise that boiling temperature and reduce anxiety about boiling over. That's why Ford added them and why most of us use them. And most that understand that don't worry about it as much as others that don't. Capish?

[FlatheadTed]

High flow pumps are not nessarly a good thing in a pre 37 motor because it creates a low pressure zone in the block . on post 36 its a different story because its pushing water so you can get a high pressure zone in the block providing you have a restriction on the out side eg Thermostats therby lowering the boiling point .This is what Ford Engineer Emile Zorrline was striving for when he moved the pumps in 37,

[Old Henry]

Originally Posted by G.M.

look at the temperature gauge in ANY old Ford and you will find what temperature normal and hot is. G.M.

Ah. But what many mis-think is that the cooler the engine the better and hot is bad. Not so. That's why Ford installed thermostats so that the engine doesn't run too cold and why the "circuit breaker" temperature sender on the engine doesn't open until well past H on the gauge. Even then, if the water doesn't boil out, no problems. So, no need for anxiety if the gauge gets above the middle position - what one might think of as "normal" - or even rides on the H in hot weather. My 160 thermostats don't even open until my gauge is at about 5/8ths and I've never boiled over even though my gauge reads H a lot in the summer. So, "chill out." Don't worry. Be happy!

[George/Maine]

Up here in Maine we run 50/50 not for Flatheads but good for -30 degs.
Runing to cool 160 degs I wish I had that problem.
I did run water the other night, because I just removed the 180 terms.
It went from 160 to 220 230 maybe just the gauge.
When I was running 50/50 and 15lb cap going to 260 280.degs
That maybe fine for some, but you could blow a gasket,hose,Its to hot.
I am at sea level.
Question for the enginers.
Say idle waiting at light, traffic jam,How much should a water pump put out the top hose at 800 rpms.
I ,m going test mine tommorow.
I,m doing both sides and see what its pumping.

[Fibber Mcgee]

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Originally Posted by geri.hilton

Most flatheads run hot always have & always will. You can fix it with a SBC

That's a pretty brave statement for this website. By the way neither one of mine runs over 190 and that's in Florida.

[G.M.]

It's really strange you guys have no idea about cooling early Fords. The 4 lb pressure cap on the early Fords was to keep the water or coolant from going out the over flow not to raise the boiling point. Also check the parts in the early parts books and see what temperature the stats were. Any restriction of the coolant flow will cause the the engine to run hot in hot weather. This includes ANY modern stats with small flow opens, any modern stats I have seen that fit in old Fords have small openings and restrict the flow. The high volumn pumps have the same effect on the 32 to 36 as they have on the 47 to 53 engines. Stock 36 pumps deliver 55 gallons in 5 minutes and Skips 92 gallons. stock 37 to 48 stock 65 and Skips 110. 49 to 53 stock 70 and Skips 110. There has been over a 100 posts from people on this site over the years that changed nothing but Skips pumps and report 20 to 30 degree cooler temperatures. Ted there are 4 or 5 types of impellers for the 36 pumps, the real truck or industrial pumps were not as bad as most others. Some have 3 small inpellers smaller than my thunb nail. With this type impeller and no pressure cap or 3lb pressure valve the engines will all run hot in hot weather. Not only do poor slipping impellers not produce enougth coolant but stir large amounts of air in the coolant. Coolant with air does not cool like solid water. George I haven't measured stock pumps for years but they haven't changed. I do know that in measureing Skips pumps if the RPMs are doubled the amount of water pumped doubles. So the water flow increases as RPMs increase. But remember at 800 RPMs the "hot water heater" is on low. The pistons are like a frying pan the more heat on the top the hotter it heats the oil spashing up on the bottom. With an oil temperature gauge as the gas pedal is increased the oil temperature rises much, much faster than the the coolant. Hot oil also increases the coolant temperature. Henry the stuff you read is what that person "thinks" and they can write anything they want just as you do with no documented temperatures or results. I'm coooler than most. G.M.

[Old Henry]

Originally Posted by G.M.

It's really strange you guys have no idea about cooling early Fords. . . . I'm coooler than most. G.M.

Once again, G.M. you are off topic. This thread is not about how to cool flatheads, which "us guys" know as much as we need to know, i.e. we run them as Ford built them and the water doesn't boil out. What more do you need to know? You're just not getting that stuff about cooling the flathead on this thread because that's not what it's about. Re-read the original question asking how hot can a flathead be run safely and the posts on the thread answering that question. Your posts are not answering that question, they are just bragging about how much you know about cooling a flathead and ridiculing the rest of us because we are not responding to your posts that are off topic.

Just keep on being "cooler than most" by anwering questions that are not asked and getting mad when no one listens to your answers.

[Old Henry]

Originally Posted by G.M.

The 4 lb pressure cap on the early Fords was to keep the water or coolant from going out the over flow not to raise the boiling point. G.M.

OK. You like real life experiments? Do this one: Run your engine at a fast idle without any air going through the radiator measuring the temperatures of the block, head and/or radiator top and see what temperature the water finally blows out of the radiator with a 4# pressure cap on. Then do the same thing again without the cap on or a non-pressurized cap on and see what the temperature is when the water boils out. I predict, based on the laws of physics without having actually done the experiment, that the difference in temperature will be 12 degrees F. i.e. the water will boil out without the 4# pressurized cap at a temperature 12 degrees below what it took to boil it out of a pressure cap. Let us know how it goes.

[Old Henry]

Originally Posted by G.M.

It should never get to the temperature of 212. G.M.

G.M. Why did you pick 212 as the temperature that a flathead should never get to?

[donald1950]

old henry, you seem to forget that lws of physics do not apply to his cars. remember: his cars oil never gets dirty from combuston blow by. always stays clean between changes.
besides most of his posts are like the old days: advertisements for his pumps and twisting his arm around to pat his back about all the knoledge he has and that no one else has on cooling.... we sure a uneducated group of people here on the barn... poor us, we will never understand, never ever........................................

[George/Maine]

I have done some tests as to what i,m looking for.
I took a gallon jug with a 1" hole full,emptyed it took 20 secs.x 3= 3 gallons in 1 minute.Thats 100% so half would be low speed is 1 1/2 gal in 1 minute.Poor flow think 1 gallon per minute .
For my problem i,m looking for a difference each side.
New style pumps.

[cuddles1]

Yho Henry: Sounds like tempers are over-heating? (ha) I am driving a 47- Ford flathead with the standard dash temp gauge; How do I know what the temp is by looking at this dash gauge? Your car looks similar to mine; 47-of 48?? Do I have to add a temp gauge??? Thanks for your reply......Dave

[Old Henry]

Originally Posted by cuddles1

Yho Henry: Sounds like tempers are over-heating? (ha)

The question is - how hot can they get before they blow??? Does it have to do with pressure or altitude? Or, just the color of the face?

Originally Posted by cuddles1

I am driving a 47- Ford flathead with the standard dash temp gauge; How do I know what the temp is by looking at this dash gauge? Your car looks similar to mine; 47-of 48?? Do I have to add a temp gauge??? Thanks for your reply......Dave

I recorded temperatures of the heads at various readings on my gauge and show them in this thread that may give you some idea. https://www.fordbarn.com/forum/showthread.php?t=61815

[cuddles1]

Thank you Henry; thats a darn good post; I have saved it for further reference. Also, must get "me" one of those temp-gauges..... Thanks again.....Dave

[G.M.]

I don't have to do any tests I did all the testing required about 12 years ago. Skip has modified several thousand sets of old Ford water pumps that have solved the over heating problems on the engines they were installed on if the instructions with the pumps were followed. George how do you measure the flow of pumps with 1 3/4" hoses through a 1" hole?? That restricts the flow just like modern stats with the small flow openings. With Skips pumps I would say 7 gallons a minute at 800 RPMs and maybe close to 3 gallons with stock pumps through 1 3/4" hose. G.M.

[Old Henry]

Originally Posted by G.M.

I don't have to do any tests I did all the testing required about 12 years ago.G.M.

So, if I understand you correctly, you learned everything there is to know 12 years ago, have known everything there is to know every since, and there is nothing new to learn?

[George/Maine]

Originally Posted by G.M.

I don't have to do any tests I did all the testing required about 12 years ago. Skip has modified several thousand sets of old Ford water pumps that have solved the over heating problems on the engines they were installed on if the instructions with the pumps were followed. George how do you measure the flow of pumps with 1 3/4" hoses through a 1" hole?? That restricts the flow just like modern stats with the small flow openings. With Skips pumps I would say 7 gallons a minute at 800 RPMs and maybe close to 3 gallons with stock pumps through 1 3/4" hose. G.M.

On the 8ba the term housing is smaller think its 1 1/4 at most.
Now is good time to test only water and no terms.
I think this block is pluged and has low flow,i expect one to be less.
I,ll check back with results.

[G.M.]

Henry I told you many times the temperature the water boils at with various caps is not an issue with the old Fords. 212 degrees is the known boiling point of water and varies a little with altitude. AGAIN I refer to the heat gauge in ALL old Fords for what is normal and what is hot. Plus the low opening temperatures of the thermostats supplied in the Ford parts books. The opening temperature has no effect in hot outside temperatures because they are wide open and it's like they are not there if the flow opening don't restrict the flow. In cooler outside temperatures the stats brings the coolant temperature up to the stats rateing and constantly opens and closes holding that temperature. There is NO reason an old Ford should run above 180 driveing down the road over 25 MPH. If it gets hotter there is a cooling system problem. The 4 lb cap is only to keep the coolant from going out the overflow and the engine running over a gallon low on coolant which causes the engine to run warmer or hot. The 4 lb cap also functions as a safety valve If the coolant temperature gets over about 212. At 212 the pressure in the system is about 4 lbs so the cap or pressure valve opens to release the pressure preventing damage to the radiator and other parts. Also if there is a compression leak this builds up even higher pressures than the hot water and releases this pressure. With a WORKING 4 lb pressure cap or Skips 3 lb pressure valve, the coolant filled up to the neck and not running much over 200 degrees occasionally in heavy traffic the coolant will remain filled for 6 or more months. Coooly your's, G.M.

[George/Maine]

Ok the results for my 8ba .060 with 4 sleves on one side.

I run 2 1/2 minutes got 6 quarts or 1.28 gallons per minute.
Other side 7 1/2 quarts 2 1/2 minutes 1.60 gallons per minute.
What I think is due the sleves/dirt one side is less.
I would feel safer with electric fan.