8BA compression issues

[mrlaser]

I have been restoring a 1951 Ford Victoria for the past 6-8 years' The engine was rebuilt in a local machine shop 6 years ago. The engine sat unused until recently. It was in a dry, climate controlled building during this time. Every few months I added MMO to each cylinder and turned the motor over. The car has now been restored and placed on the frame. I have been unable to start the motor in spite of the fact that the carburetor, has been professionally rebuilt, the distributor ,which is NOS, has been set up on a Sun machine and the remainder of the ignition system is new. There is fuel coming from the accelerator pump and there is a good spark at the plugs when grounded on the block. The system is 6 volt and positive ground. The tdc was set by putting a rubber cork in #1 , turning the engine over until the cork popped. The pointer points at the bump on the crank pulley. When I did not get ant apparent firing, I decided to (belatedly since the engine was rebuilt) check the compression. All cylinders are 29-30 pounds. I am at a loss to explain this. I can understand that with the prolonged sitting some of the rings might have become stuck, but not all of them. BTW the engine was bored, the crank reground and the cam reground at a cam shop. New pistons,rings, bearings etc. Ideas.?

[flatford8]

Prolonged running on an engine stand isn’t a good idea but, was this one ever run at all?..... Do you know if it ever had compression after the rebuild?.....try some type of penetrant and turn it over with the plugs in..... ark

[Bob C]

Do a leak down test, that will tell you where you are losing your compression.


Bob

[Kurt in NJ]

I have gotten compression back on engines that have been sitting and had debris on the valves causing low compression be using a air hose blowing air into the cylinder and cranking, I used the hose adapter that is used to put shop air into cylinder - then crank with starter----- this assumes that engine was put together correctly

Possibly the cam timing is off, look at valve position, when ex is just about closed, and intake is just starting to open the piston should be at top center--- easier done if car can be rolled in top gear

[c612pro]

Fuel coming from accelerator pump usually means the carb is flooding. Check for dirt in the fuel system and check the needle and seat. Common on first fire up to collect assembly dirt in the system.

[mrlaser]

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Thank you all for the suggestions. I plan to do a leak down test later this week. The noted fuel is only when the throttle is opened. I don't remember whether this engine was rebuilt with adjustable lifters. I had a second flathead built by H&H at that time and I am not sure which one had them. Would insufficient valve clearance be a possible cause? It seems that the nearly identical readings in all 8 cylinders would be awfully coincidental without some common problem.

Unfortunately, I have moved away from the area where the rebuild was done and lost most of the paperwork on the build. I plan on calling the shop to see whether they may have some records in their files re.the work done

[mrlaser]

Also, the engine has never been started either in the car or on an engine stand.

[JWL]

With all the cylinders being low and equal it might have a cam timing problem. If the leakdown shows little problem that is something to consider.

[Mike51Merc]

I'd suspect your valves aren't fully closing.

[RalphG]

Fully, or partially stuck valves are pretty common on a flathead v8 that has sat for years. Both my 39 and 52 had zero compression on a few cylinders after a long rest and it took a little work to loosen them up before they would seat. Keeping the cylinders oiled is good but it won't get up to the valve area on a flathead.

[Frank Miller]

If you can easily hook up an air hose to your spark plug hole that will tell you everything. All you're looking for is where the air is escaping. If you hear it through the fill tube then it's rings. The carb is an intake valve and the exhaust will be coming out the pipe. Did you try oiling the cylinder with motor oil and redoing a compression check? I had a 70 chevy 6 cylinder I had to replace the head on due to a couple of cracks. It was running but I could not get it to start. Seems the coolant had washed down the cylinders and and there was no compression. A little oil in all the cylinders and it came to life. I imagine the rings were a bit worn also but it ran well enough.
Your rings have not been seated and even though you oiled them they may have dried out. Good luck.

[modeleh]

I just had a similar issue with a flathead 6 Continental on an air compressor when I went to sandblast my Model A body last month. The motor had sat unused for several years but was loose enough to turn easily by turning the fan by hand with the plugs in. Wouldn’t fire up for love nor money until I removed each plug and squirted a few pumps of motor oil in each cylinder with a pump can. Replaced the plugs and it fired and ran instantly. Smoky for the first few minutes but once it ran there was no issue again you could shut it off and restart it no problem. Give it a try you might get lucky like I did.

[mrlaser]

I did a leak down test with disappointing results. All the cylinders except one were at 45-50% with the air leak coming from the carburetor. The remaining cylinder was 80% with air escaping from the carb and the exhaust pipe on that side. Next I plan to remove the intake and that followed by the heads if necessary. The engine has adjustable tapers so I wonder about the valve clearance.

[drolston]

Have you verified that crank gear to cam gear is properly timed, per Kurt NJ suggestion?

Very unlikely that valve clearance is the problem on all 8 cylinders. Probably rusty valve stems causing sticking valves.

[mrlaser]

The crank gear issue is still an unknown. I did speak with the engine builder who assures me that the marks on the cam and crank were aligned. I have had a limited amount of time to work on the problem and garage temperatures near 100 haven't been conducive to my productivity.

Re: the valve clearance, in view of the fact that all of the cylinder compression readings are 40 ((except one at 20) I just wonder whether a small error in the valve clearance might prevent complete closing. Obviously, the one outlier is likely stuck as well.

[Fordestes]

When you check the timing marks make sure someone didn't add their own set of marks on the gears , I seen this happen when a person un familiar with the engine tried to do the right thing and put their own witness marks on the crank gear, thus creating a problem for a later rebuild. the crankshaft keyway will be at approx. 10 o clock when the cam and crank gears are aligned together.

[40cpe]

When you pull the intake and check the valve clearance you should know more about stuck valves. If valves are stuck the clearances should be more than spec.

[mrlaser]

Thank you all for the suggestions.

[Kurt in NJ]

Have you tried blowing compressed air into the cylinders while cranking, this I have found blows debris out of the valve seating area, I have used this to get compression back in several engines that have been sitting

[mrlaser]

I have not, but will before taking the disassembly step. It had been mentioned before but I forgot to try the suggestion. What kind of pressure do you suggest? Thanks again to everyone.

[Kurt in NJ]

I have used regular "shop air"--160 lbs or so

[mrlaser]

The leak down test resulted in leakage through the carburetor. I removed the intake manifold and the passenger side head. I checked TDC on number 1 and confirmed that with the piston at it's peak elevation on a dial indicator. The bump on the crankshaft pulley was aligned with the pointer. The valve lash was actually excessive being .018 at the narrowest. I have removed#2 intake and exhaust valve and guide. They were easily extracted. Unusually, both guides had the "o" ring installed. It makes me wonder whether the correct, later springs were used? The valve and the seats looked good. Any thoughts or suggestions?

[cadillac512]

If it were me at this point I would place #1 piston at TDC and slowly rotate the crank pulley 2"-3" left and right watching the valves on that cyl. If they don't move,rotate the crank a full turn and check again. (at this point #1 is on the overlap stroke and turning the crank slightly one direction opens one valve and slightly the other direction opens the other one). As the piston passes over TDC one valve will close while the other opens. If this occurs right at TDC or VERY close, the cam timing is correct and the problem lies elsewhere. If it's very far off, you'll have to pull the front cover to correct the cam timing by lining up the gears correctly.
There have been cases where gears were incorrectly marked....


Terry

[mrlaser]

Thanks for the suggestions. I'll do that in the next day or two.

[mrlaser]

Terry,
I did as you suggested and confirmed that the valves began to open when the engine pulley was moved 2-3" to the right and left of the bump on the crankshaft pulley. Number one exhaust when the engine was rotated clockwise and number 1 intake when rotated counterclockwise. So, I am assuming that the cam timing is correct. Would using the earlier style valve springs contribute to a loss of compression? In the Ford manual the later springs have 7-10 pounds more closing force than those used on the non rotating valves.

[mrlaser]

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Also, as suggested earlier, I will lap the valves.

[40cpe]

Originally Posted by mrlaser

Terry,
Would using the earlier style valve springs contribute to a loss of compression? In the Ford manual the later springs have 7-10 pounds more closing force than those used on the non rotating valves.

the rotating valves used a keeper that required shorter springs than the non-rotating valve. A pre-EAB engine would use the longer spring with a non- rotator keeper.

[cadillac512]

Originally Posted by mrlaser

Also, as suggested earlier, I will lap the valves.

It sounds like the next step since valve timing appears to be correct. The springs really shouldn't be the cause of your poor compression testing results. Any spring capable of closing the valve should allow an accurate compression test at cranking speeds if the valves are sealing well and they have lash.

Terry

[Tinker]

It's a rebuilt engine. run the shit out of it and then report back. Rings are probably not set or valves. A motor needs to be driven.


Certainly if there is a metal on metal issue...stop. otherwise.

[cadillac512]

Originally Posted by Tinker

It's a rebuilt engine. run the shit out of it and then report back. Rings are probably not set or valves. A motor needs to be driven.


Certainly if there is a metal on metal issue...stop. otherwise.

The problem with that is the engine won't start yet due to the extremely low compression issue. Hasn't ever been run since the years-ago rebuild. I do believe he's on the right track and following a logical troubleshooting sequence. It's just being obstinate like these things do...to test us!


Terry

[mrlaser]

I'm hoping that I may have found the issue. The valve on the left is before lapping while the valve on the right is after lapping.

[mrlaser]

A 3 angle valve grind was done during the engine rebuild, but the valves were apparently not lapped.

[big job]

Valve lapping is a good sign. However these days no one laps valves anymore a shame.
Heres how we do it; with out valve keepers we stick a shop vac onto a intake port and
the shop vac will snap the valve out of your hand, same with the exhaust then a little PB
blaster on said valve if it doesn't get dry or visual bubbles thats good. Should have said
drop all valves in and do one at a time using the shop vac. Due to I hate mate and the written BS. remove cam gear and rotate by hand to feel the heal of the cam, I learned
that in school my buddy totally blind 'those days there were no brail books. Blind people have superior feel and hearing. Teacher would scratch his head cause this kid would grind valve stems with in a tenth: You will be good with .010 intake and .014 exhaust.
As already said some re pop timing gears are not stamped correctly so watch that. Now
if satisfied put back together get the battery open throttle turn engine over'starter' put
your hand over carb. you now should feel vacuum, or try 12vt battery no vacuum and
no vacuum on your hand means no no way it will start ! (piston goes down it sucks fuel)
Hopes this helps. sam

[Tinker]

Originally Posted by cadillac512

The problem with that is the engine won't start yet due to the extremely low compression issue. Hasn't ever been run since the years-ago rebuild. I do believe he's on the right track and following a logical troubleshooting sequence. It's just being obstinate like these things do...to test us!

Terry a flathead will start with 30lbs compression. It'll run bad with no power, but if you have some vacuum and if you have a decent ignition/spark and fuel, it'll fire. It's not a diesel engine.


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


But who knows on this one...

[mrlaser]

I have seen that video before. It only increases my frustration that even after a complete rebuild , it won't even try to start .

I am nearly finished with the valve lapping. Does anyone have an alternative way of replacing the valve spring keepers since I assume that few people have the tool pictured in the green Ford manual?

[mrlaser]

I am referring to the spring compression tool rather than the keeper insertion tool. But, suggestions for both would be welcome.

[mrlaser]

While waiting for suggestions, I came up with this solution. I found a washer with an inside diameter which matched the diameter of the valve sleeve. I epoxied the washer to the valve spring compressor to ensure stability. This enables the valve spring to be compressed and the keepers to be put in place. The unit was placed in a vice to allow both hands to be used. It worked perfectly. I'm sure there are other ways to safely install the keepers but this worked for me.

[mrlaser]

Another view.

[Frank Miller]

I did mine in a drill press.

[Bored&Stroked]

Since you have the heads off - oil the bores a bit while you're at it (I use my hand to manually rub in some engine oil or assembly lube). Also, use some decent assembly lube on the valve stems (where they're in the guide) and might as well put some 'break in' lube on the bottoms of the lifters. This engine has sat awhile, so getting her "greased up" is never a bad thing.

On cam timing - I think your check is good, but just to further elaborate. If you have #1 cylinder on TDC (compression stroke), then both valves should be closed. As you rotate the crank clockwise, you should see the exhaust valve just start to open right before BDC and as you continue around the exhaust should fully open on the way back up (exhaust cycle) - and when you're back to TDC, the intake should have just started to open and the exhaust is just about closed. (This is the beginning of the intake cycle).

My bet is that the valves were not seating - due to however they did their work and the need (in this case) to lap them a bit. The valve you showed was probably an exhaust valve - given the big/wide seat on it.

Keep us posted - nice work on your end!

[Bored&Stroked]

Originally Posted by mrlaser

Another view.

Good Imagineering! I used a little "tool" I made on my lathe - on my drill press (pushes the retainer down so I can put the keepers in).

[mrlaser]

Thanks so much for the comments and suggestions. I will double check for the correct timing of the valve movement later today. I do have the necessary lubricants on hand and will be using them as things progress.

[mrlaser]

The valve movement was exactly as described. When reassembling the top end, would it be ok to place one head on without the intake to assess the compression on that side ? I certainly hope that there will be a significant improvement, but would like to see some actual numbers before reassembling everything. As has been suggested, I do plan to do a preliminary check on the sealing of the intake valves by using a shop vac on the intakes. Since the engine is in the car with an exhaust system installed, i'm not sure about doing that test on the exhaust valves. Any thoughts or suggestions would be greatly appreciated.

[Bored&Stroked]

If you're seeing a good solid "lapping" area on the valves/seats, you really should be good to go. I would blue die-chem (or magic marker) the seats as well - just to make sure that the seat has a really nice lapped area (that there is no issues with out of round or other sealing conditions).

On the intake side, I've turned the stand such that the deck is parallel to the ground (down) and poured a little lacquer thinner into the port (use a syringe) - then you can look on the chamber side of the valve for any weeping around the valve. If you find one, just use fine lapping compound and do it again - until none are weeping.

You can do similar tricks on the exhaust - is just a bit more of a pain to do . . . so the vacuum cleaner might be your friend.

Good luck!

[mrlaser]

I did do the Magic Marker on all the seats. The marker was removed with a few turns of the valve lapping stick.

Fortunately,or unfortunately the motor is in the car, not on a stand. That is the rationale for the shop vac and something like PB Blaster to check for leaks. I suppose that I could connect the vacuum to the tail pipe on each side to do the exhaust side. Thanks again for your Imput.

[Bored&Stroked]

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Me, I'd not want to pull a bunch of solvent onto the tops of the valve guides - might remove lubrication of the valve stems (just thinking out loud here). So I would trust my lapping and not worry about the vacuum cleaner.

[JSeery]

I'm with B & S here, don't really think the vacuum cleaner is going to tell you much on anything. If the valves are assembled correctly and seating correctly it should be good to go. If not I would thank removing the intake (and even the heads if it is required) would be less effort than trying to rig up a test using a shop vac.

[Desoto291Hemi]

The lapping looked very good to me,,,,a nice even pattern,,,centered in the valve face too.
Good job.

Tommy

[mrlaser]

Actually the heads and intake are still off while I check the valve lash. Thanks for all the help. I will post a follow-up when the engine is back together (and running...I hope)

[AnthonyG]

Im not an expert on Flattys for sure, done the normal pull plugs replace & tune it up. I e had many Mid ‘60’s GM engines apart & think after building startup should happen right after rebuild to seat everything, more time unstarted amplifies w Unstarted new rebuild low compression is possible until seating internals. That one left the garage so try this before disassembly. Drain a quart of oil & replace w STP poured equally in each spark plug holes & turn the engine over letting STP coat cylinders & rings. Lightly Redress plugs w point file reset & Replace plugs, prime carb w fresh gas (have fire extinguisher handy) no ethanol if possible & see if she fires up. If so if all sounds good don’t shut it down & let run for 30 or so minutes. STP should give compression a boost needed to more easily start as long as if as stated all setup right when built.

[mrlaser]

Currently the engine is still at the short block stage. When I am ready to try to start it, I will be changing the oil. As suggested, I will add a qt of STP at that time. Thank you for your help.

[AnthonyG]

Don’t forget, put STP in spark plug holes last & crank engine quickly after, sequence important to insure distribution of STP on rings & cylinder just before trying to start. BOL

[mrlaser]

Will do. Thanks again.

[mrlaser]

Update: I have adjusted all the lifters to the recommended settings. As mentioned before, all the valves have been lapped. After reinstalling the right side head, I repeated the compression test. All 4 cylinders were improved but still low at 65#. Added oil brought this up about 5#. ( this engine has never been started since the complete rebuild)The intake is still off so I verified that the valve lash was correct when the leak down device was functioning. The leak down test indicated that all the leak was from the individual intake valve oriface in the block.. I have no idea which valves were used in the rebuild. Is it possible that the valves aren't entirely seating because the stem is being held up slightly in the guide? The intake and exhaust valves are all identical and are stainless steel. Not sure what to do next. Help.

[mrlaser]

I should mention that I lapped the valves with the guide in place but without the clip in place to make the guide depth consistent. That might explain why the lapping was accomplished. When the valve lash adjustment was done it was the assembled valve unit in place with the clip installed.

[flatjack9]

Were all of the intakes leaking?

[mrlaser]

well, I have only tested the 4 valves on the right side of the engine, all of them were leaking about 60% on the leak down gauge.

[mrlaser]

I am wondering whether lapping without the clip in place might have masked the fact that the valve might actually be hanging up once the valve unit was clipped in it's proper position. In other words since the guide was not in a fixed position, if was free to move to whatever depth was necessary for the lapping to be accomplished.

[40cpe]

I think you might be on to something. If the guide is interfering with the valve, it can't be much. I thought about driving the guide down without the spring and see if the clearance changes, but probably not enough to measure. I think I would try removing about .005-.010 from the top of the guide. You might do some close measuring on one of the valves from the side with the head off.

[mrlaser]

Actually, I pulled the head on the right side and removed the #1 intake valve unit. The mid stem measures 0.342 while the area immediately above the guide measures 0.344. Above that there is a suggestion of a shoulder and the stem tapers up into the valve head. Pushing down on the valve head to compress the spring results in the valve stem becoming "wedged"in the guide opening. It seems that this might prevent the valve from seating properly once the clip is put in place with the resultant spring compression. Any other thoughts or suggestions would be appreciated. Thanks everyone for your help.

[mrlaser]

Sorry for the double post. I had to edit the picture size.

[40cpe]

can you look down the intake port and see if the stem goes that deep into the guide?

[mrlaser]

I'll try. I'm wondering about having the stem below the head ground to match the remainder of the shaft which slips easily in the guide. It is 0.004 larger than the lower shaft.Any thoughts?

[40cpe]

I looked at a 59 block I have and can see the port under the valve through the intake runner. I think you can see how far the head is from the top of the guide. With a good light I think you will be able to see if all of the stem is in the guide or not.

[mrlaser]

Forty CPE ,Thanks for helping me see the obvious. I'm afraid that in my hyper focus on the valve stem, I missed the "forrest for the trees" . I did as you suggested and (with a good light source) viewed the valve stem and it's relationship to the guide when the valve was closed ( with proper valve lash present). As can be seen, the slightly wider portion of the stem is not interfering with the guide. With that possibility eliminated, could valve spring preload be a factor? I had no way of testing the springs that I installed.

[flatjack9]

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Valve spring preload would be a factor if it's not long enough to firmly hold the valve on the seat.

[40cpe]

I see he had to fabricate a tool to install the valve locks, I don't see that as a issue. I have a measured 45-50 pounds and I installed mine by hand.

[JSeery]

Originally Posted by mrlaser

Forty CPE ,Thanks for helping me see the obvious. I'm afraid that in my hyper focus on the valve stem, I missed the "forrest for the trees" . I did as you suggested and (with a good light source) viewed the valve stem and it's relationship to the guide when the valve was closed ( with proper valve lash present). As can be seen, the slightly wider portion of the stem is not interfering with the guide. With that possibility eliminated, could valve spring preload be a factor? I had no way of testing the springs that I installed.

Then how did you determine the install height? You don't just stick the springs in there, you have to determine the spring height at the seat pressure you want and then shim to that install height on the valve assembly.

[Tinker]

Might be time for new block seats.

[mrlaser]

When the engine was rebuilt by the machine shop the cam,valves ,springs, and adjustable lifters were purchased by them. I do not know the source of the products. The intake valves are 4.829 in length. After lapping the valves and changing the valve springs to the shorter type shown in the Green Manual for the later rotator valves, the compression improved from the mid 40's to approximately 65 psi in all cylinders. With added oil there was an additional added 5 psi. At the time I did not check the height or set the proper spring pressure. I was aware of these steps but thought that ( as mentioned in Mike Bishop and Vern Tardel's book) this step was for a "performance engine". Being a novice at this, I incorrectly assumed that since my engine was to be a stock rebuild, I could simply put the springs in place without those two measurements. ( live and learn). I am now redoing the springs after making those calculations. I will report on the results when things are back together. The attached picture is of the intake valve and the initially installed taller spring on the left and on the right, the shorter spring used with the "51-'53 rotator valves which were in the engine originally. Thanks again for all your help.

[flatjack9]

You must use the proper retainers with those springs. There are 2 types of retainers.

[mrlaser]

Yes, I do have the spring retainer and sleeve type. Thanks for the advice.

[mrlaser]

I have now finished checking valve install height and setting valve spring pre-load via a spring scale and shims. And while I did follow the suggestions offered by Cadillac512 regarding cam timing verification, I would like to be sure that my current assumptions are correct before reassembling the heads and intake. TDC was established by bolting a plate across number one cylinder marking the crank pulley in both the clockwise and counterclockwise direction. TDC was determined to be 1/2 way between those marks as seen on Marts video. It also coincided with the "bump" on the crank pulley being opposite the existing pointer. At that time both valves were closed and the proper valve lash was present on both valves on number 1 cylinder. Number 6 piston was at also at TDC at that point with the exhaust valve closing just prior to number 6 reaching TDC and as the engine passes through TDC the number 6 intake just begins to open. This is my novice understanding of "valve rocking". I have seen some mention of valve overlap in other threads, but I am not seeing any point during this transition where both valves on number 6 are open at the same time. I am wondering whether this is more of a phenomena seen with higher performance cams? The cam in my engine is of the stock variety. I am new to most of these issues and want to be sure that the cam timing concerns have been properly sorted before moving on. I greatly appreciate all of your suggestions.

[flatjack9]

You know #1 is on the passenger side and is not the forward most cylinder as in most engines. Sounds like you have them mixed up.

[mrlaser]

I do hope that that any confusion was in my description. In the attached pictures, I believe that #1 is just below the thermostat on the passenger side of the engine, while # 6 is the second cylinder from the front on the driver"s ( left side of the engine)

[cadillac512]

You have it absolutely correct. Your description of "valve rocking" and assumption that more performance oriented cams will make the lift at tdc while rocking more apparent is spot-on. Well done...I'll bet she fires up now!


Terry (out in the shop building my new 260 Merc flattie right now!)

[mrlaser]

Thanks, that's a relief. Fingers crossed!! I will report back.

[Kurt in NJ]

On post 70 , the picture of the valve it looks like the (if it is one that is lapped in) it looks like the seat is very wide

[mrlaser]

You're correct. When I was lapping that valve (#4) I was leaning over the '51 front fender with one foot in the air and fighting the heater motor.. At the time I didn't realize that the valve guide had slipped down into the gallery. It was only for a few strokes. After realizing what had happened, I covered the valve with Magic Marker and checked the pattern. It yielded the same narrow band as the others. I would have replaced the valve itself. But I don't know who the valves were originally purchased from. Thank you for catching that mishap

[Bored&Stroked]

Can you take a close up picture of a couple of the cylinder bores? Close as you can, with some light and good focus? I'd like to see what the cylinder walls look like. Thanks!

[mrlaser]

B&S, These are the best pictures that I can get with my phone. There are some residual bits of the head gasket on the walls and the pistons which I haven't removed.

[Bored&Stroked]

Hey Mr. Laser - do you see any hone cross-hatch marks in the cylinders? I don't think I can make any out (might just be the pictures)? As this engine is new - was wondering if the rebuilder did the "normal" stuff that we always do . . . which is all about getting the new rings to seat.

[mrlaser]

B&S, it doesn't appear that there is any significant cross hatching. As I mentioned above, the records of the build were lost by the movers and the builder has passed away. I did notice a significant jump in compression, on repeat testing, with added oil. From 65 psi to 90 psi. What would you suggest might be my options? Thanks for your help.

[mrlaser]

It's a bit frustrating, coming at the end of an 8 year restoration project. But. As they say "you need to play the hand you've been delt"

[Sid]

If you're running close to 90 lbs on all cylinders button it up and start it. as long as there is not much over 5 lbs difference between cylinders. Once the motor is run and warmed up the compression will be even higher. Also the elevation plays a slight role in compression. The compression will be slightly lower a say 5,000 ft. as opposed to sea level.

[mrlaser]

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Will do. Thanks. Unfortunately, ( except for the weather) I'm at sea level.

[flatford8]

That’s a beautiful car!!!...what ever it takes to get to the end result.......will be well worth all your efforts.....Congratulations!!!......Mark

[Bored&Stroked]

If you're getting 65 - 90 lbs at cranking speed, I'd get it back together, get it started (check for leaks and retorque the heads) and then I'd put it under highway load as soon as possible. It will be key for the rings to seat and it kind of looks like there isn't much cross-hatching or honing in the cylinders.

Don't make the mistake of letting it idle/run for a long time in the garage - get it on the highway and do some heavy acceleration runs. The last thing you need is to glaze down the cylinders - the rings will never seat and you'll have perpetually low compression and low power.

Once you've done that at least a half dozen times, then drive it for a good length of time (couple hours) - with varying speeds and accelerations. Then take it home, let it cool down and do another compression check - you'll then know if things are in good shape or not.

Best of luck - you've been working your butt off on this - we're all hoping for a great outcome!

B&S

[cadillac512]

B&S has the same opinion as I do...Get everything ready to drive, fire it up, do a quick check for leaks,noises and check the ignition timing. Then get on the road and drive it as suggested. Nothing wrong with fairly heavy load for short bursts-it'll help seat the rings. Idling is bad so keep that to a minimum at first. Monitor the gauges and enjoy the ride!



Terry

[mrlaser]

Thanks everyone for all your help and suggestions. I will keep posting with any progress. Happy Thanksgiving to all.

[Sid]

With that being a fresh engine and I might assume a reground cam or new it may be wise to use a break in oil in the beginning. Due to the lack of Zinc in today's oils. And add a dose of additive at each oil change. I realize flatheads don't have the valve spring pressure a ohv has but it is good insurance. I myself use Royal Purple break in but I'm sure there are other brands just as good. Just be sure it states fortified with a healthy dose of Zinc

[mrlaser]

Will do. I am hopeful that there will be a need for the break in process. I appreciate everyone's thoughtful suggestions and help. I have learned a lot.

[cadillac512]

Hey, mrlaser- anything new to report? The anticipation is killin' me!
Terry

[mrlaser]

Sorry for the radio silence. I'm away for the Thanksgiving holiday. I will definitely report my experience asap. Thanks for your concern and curiosity.

[mrlaser]

I am getting ready to attempt to start the motor. The engine is installed in a '51 Ford. Everything is stock including a positive ground, 6 volt system with a 1 year old Optima battery. This was the first year of the later, more common key start ignition. During prior attempts to start the engine, the rate at which the starter turned the motor over seemed somewhat slow. Utilizing a 6 volt boost charger helped somewhat. Others have mentioned using a 12 volt battery to provide a faster rotation to facilitate starting. If I were to do that, would I connect the battery directly to the starter, or put it in place of the 6 volt battery. The only 6 volt accessory which is supplied with continuous, non switched, power is the clock. The coil is a new 6 volt variety supplied by one of the early Ford suppliers. Would it likely have an internal resistor? Any advice would be appreciated. Thanks in advance.

[tubman]

I have a '51 Ford with a 255" Mercury and Edmunds heads, which should be as hard, if not harder, to spin over that your engine. An Optima spins it over just fine. Before resorting to a 12 volt jump, I would spend some time inspecting and cleaning ALL of the connections, Including grounds. A 12 volt should not be necessary.

[Sid]

Many times with a rebuilt flathead the first time you try to start they crank slowly. This is usually because of the seal on the oil pan. Once you do get the motor started and it runs for a short time it will loosen up when the seal wears in. If you are concerned about 12 volt to your gauges etc. on the starter solenoid on the side from the battery you may see a other wire on that solenoid post also. If you remove that wire off that post (approx 10 ga.) that pretty much cuts power to the gauges radio headlights heater etc. You will need to then hot wire the ignition and cross the solenoid under the hood. The cable that goes from battery to solenoid. That post on solenoid to the small post on solenoid. If your coil is hooked up proper hotwire goes to - post on coil. Just stay away from the dist. side of coil so you don't cook points. Once the motor has run for 5 minutes or so it should start easily on 6 volt and remember not to let slow idle. You need to break the cam in.

[marko39]

You can use a 12volt but just hook to starter, you don't want 12 volts going to the rest of the car. If it turns slow when cold it will probably be worse when warmed up. Was the starter rebuilt?

[Ross F-1]

Are the battery cables #00 gauge, very heavy duty? Common cables carried in auto parts stores are #2 or #4, made for 12v systems, nowhere near up to the 600 amps a 6v car draws in cold weather.

[mrlaser]

Thanks for the input. I will , of course, try with just the 6 volt alone and possibly with the 6 volt boost. I did notice, before the latest tear down, that the compression readings were 10-15 PSI greater when the 6 volt boost was applied. That's why I wondered about the use of 12 volts to aid with starting. The cables are less than a year old and were purchased from a major early ford supplier. Unfortunately no description as to the wire gauge was listed in the catalog. They were, however listed for the '50-'53 V8. I will check on all the connections prior to attempting to start the engine. Should it actually start, I will only run it for a few minutes since the rings are not seated and it will not be under varying loads.

[mrlaser]

Oh, and as to the question about the starter, it was rebuilt at an auto electrical shop before it was installed.

[tubman]

Good luck. I find one of the most gratifying parts of this hobby is the initial start-up of a new (or revived long-slumbering) engine.

[mrlaser]

Thanks, I'll probably need that luck.

[Bored&Stroked]

You'll get through this Mr Laser . . . you have the right attitude and are not afraid to get your hands dirty. Best of luck with your startup!

B&S

[mrlaser]

I'm hopeful. Thank you.

[Sid]

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Any news on the 8BA?

[mrlaser]

Actually I am away for a week. I will follow-up when I can get back on the " problem". Thanks for your interest.

[mrlaser]

As promised I am again posting with an update on the issues that I have been experiencing.

As far as cam timing goes. What I have is identical to that shown on the engine in Mart's attached video, (as seen between approximately 18 min and 22 min in the video). I have verified the exhaust valve movement with the dial indicator shown in the attachment.

https://youtu.be/dn446jjCVR

He is demonstrating valve action on an earlier engine than mine, but it does look like a "crusty" old original. Also, since my cam was reground, I'm not sure what settings were recommended by the cam shop. As I may have previously mentioned, the original engine builder has passed away.

On previous posts, I have mentioned how slowly the engine turns over on 6 volts. When checking the grounds and the cable at the starter lug, I noticed that the starter case was stamped "12 V ". As a result, I connected a 12 V battery to the starter side of the solenoid leaving the "key" side connected to the 6 volt battery, then turned the key to the " on " position ( not using the "start" feature). When the starter was activated by directly connecting it to the 12 volt battery, the engine turned over rapidly. With that setup, repeat compression checks resulted in readings ranging from 78-90 PSI.

In spite of this, there was still no firing. I next checked the intensity of the spark which was regular, but very weak. It would only jump a gap of 1/16" when the center coil wire was held near a head bolt. I located a FoMoCo set of points and condenser and added another ground from the engine to the frame with no change in the intensity of the spark. I have a NAPA. Echlin coil coming next week to use in place of the "off shore" coil that I now have. The distributor is an unmodified, cast iron type LoadoMatic with the cast iron timing cover. We'll see if that helps.

BTW, the carburetor is squirting fuel when the accelerator linkage is pumped.

All very frustrating. Looking for any and all suggestions. Thanks to all who have contributed their knowledge and help thus far.

[Bored&Stroked]

Sounds like you're onto at least one issue. Given that it has almost no spark, it surely isn't going to start. Given your compression readings - seems like the rings really aren't seated (and as it's a new engine, not terribly surprising). Once you get a good ignition on it, we can only hope it will fire. Make sure the coil you're going to use has the correct voltage going to it . . . good luck!

[mrlaser]

Thanks once again B&S.

[Sid]

Be sure that the ignition wire goes to the - on the coil goes to the key and the + goes to the distributor. If you have an ohm meter check the coil. You put one lead on the + and the other on the - terminal. You want about 1.5 ohm. If all checks out Maybe hotwire the coil and see if spark improves. Neg batt. to neg - coil and see if you get better spark.

[mrlaser]

I'm sorry that I failed to mention that I have also tried to directly connect the coil to the battery as well as being sure that the coil was connected correctly. Early on I had connected the coil incorrectly and melted the fiber block on points. Haven't made that mistake again.I have also used a multimeter to check the coil but I haven't known what the exact specifications for this particular coil should be. It's hard to remember everything that has been tried when typing for this thread. I really appreciate any and all suggestions that the members of this forum have offered. Thanks to all.

[JSeery]

What coil are you running?

[mrlaser]

It is a 6 volt canister type, purchased from one e of the well known early Ford parts suppliers. There is no significant information on the box.

[mrlaser]

FINALLY!! After replacing the coil with the one manufactured in the USA, the engine tried to start. I had set the distributor to the TDC position on #1 to check the spark intensity. The grounded plug had a vigorous,bright blue spark . Without changing anything, I replaced the plug and plug wire and turned the key to the "on" position. The cylinder fired as the key was turned and moved the crankshaft pulley nearly 45 degrees from the TDC. position. I haven't tried anything else yet because of other commitments. Hopeful.

[Sid]

Coils don't really care if they are 6 volt or 12 volt. On a 12 volt system the resistor cuts voltage nearly in half anyway. It's the ohm rating to be concerned with. 1.5 or thereabouts on primary side is what you want. To test the secondary side put your meter on 20K. Put one lead on the + post and the other lead in the coil tower. You want a reading of around 9,000 give or take 1,000 or so. 3.0 ohm on primary side is usually considered a 12 volt coil. Also is there any chance you purchased a bad condenser?

[JSeery]

Originally Posted by Sid

Coils don't really care if they are 6 volt or 12 volt. On a 12 volt system the resistor cuts voltage nearly in half anyway. It's the ohm rating to be concerned with. 1.5 or thereabouts on primary side is what you want. To test the secondary side put your meter on 20K. Put one lead on the + post and the other lead in the coil tower. You want a reading of around 9,000 give or take 1,000 or so. 3.0 ohm on primary side is usually considered a 12 volt coil. Also is there any chance you purchased a bad condenser?

Sid, this depends on the coil. Different coils have different internal ohm ratings. A lot of the older coils were basically the same (around 1.5 ohm internal resistance) and would work on 6v without a ballast resistor and on 12v with something around 1.5 ohm ballast resistor. BUT, there are 3.0 ohm coils and coils with much less than 1.5 ohms and about everything in between, so you really need to know which coil you are working with. Examples:

The Flame Thrower 40,000V coils have internal resistance rated at 1.5 or 3.0 ohms.
Flame Thrower II coils have lower resistance at 0.6 ohms.
Flame-Thrower III coils have extremely low resistance of 0.32 ohms.

These are just Flame Thrower examples, almost all coil manufactures provide coils with different internal resistance.

Note: The extremely low ohm coils are used with different types of electronic ignitions and not with a points distributor, but some look a lot like a normal coil. It is best to check them if there is any question.

[mrlaser]

Well the first two coils that I had tried tested 4.2 and 3.7 ohms when the multi-meter leads were placed on the pos and neg terminals. When the secondary circuit was tested they had readings of 9.14 and 8.39 K ohms. The NOS NAPA 6 volt, Echlin coil that I installed today had readings of 1.5 ohms on the primary circuit and 9.53 K ohms on the secondary. While I don't pretend to know much about this situation, I do know that the spark was much stronger with this latest coil.
As far as condensers are concerned, I have tried 3 different ones but currently have a genuine FoMoCo one in place with a Motorcraft set of points. The other condensers are of unknown origin.

I'm hoping there's a light at the end of the tunnel and that it's not a train

[Sid]

The Flame Thrower 40,000V coils have internal resistance rated at 1.5 or 3.0 ohms.
Flame Thrower II coils have lower resistance at 0.6 ohms.
Flame-Thrower III coils have extremely low resistance of 0.32 ohms.

Yes that's true that you need to know what coils you're dealing with. I didn't think about factoring the aftermarkets like pertronix and the very low resistance coils. I was thinking oem point style coils from 50's to 70. I myself am running a Pertronix 40011 as a 6 volt positive ground rated at 1.5 ohm. I think that one also comes in a 3 ohm rating.

[Bored&Stroked]

One thing to know Mr Laser is that in many cases if you find a old NOS condenser, it can be shot inside. I would get a new NAPA Echlin condenser - but maybe wait until your next set of tests. It is never good to change two things at once!

[JSeery]

Originally Posted by mrlaser

Well the first two coils that I had tried tested 4.2 and 3.7 ohms when the multi-meter leads were placed on the pos and neg terminals. When the secondary circuit was tested they had readings of 9.14 and 8.39 K ohms. The NOS NAPA 6 volt, Echlin coil that I installed today had readings of 1.5 ohms on the primary circuit and 9.53 K ohms on the secondary. While I don't pretend to know much about this situation, I do know that the spark was much stronger with this latest coil.
As far as condensers are concerned, I have tried 3 different ones but currently have a genuine FoMoCo one in place with a Motorcraft set of points. The other condensers are of unknown origin.

I'm hoping there's a light at the end of the tunnel and that it's not a train

If you checked the first two coils correctly that would sure present a problem! Looks like your on the right track now. Never know what you have until you check.

[mrlaser]

I have checked both of the original coils with two multimeter. They gave similar results. The attached picture is with the inexpensive meter because it has a flat bottom. I needed that feature to free up mu hands to take the photo.

[JSeery]

Originally Posted by mrlaser

I have checked both of the original coils with two multimeter. They gave similar results. The attached picture is with the inexpensive meter because it has a flat bottom. I needed that feature to free up mu hands to take the photo.

Yep, that is not going to work well with a 6v system!

If your interested in the math, Voltage/Resistance = Current (V/R=I). In general terms you want around 4.0 amps at the points. So, at 6.0 volts and 1.5 Ohms resistance the Current would be around 4.0 amps. With the 3.5 Ohm coil it would be 6.0v/3.5 Ohms = 1.71 Amps which would result is a very weak spark.

The ignition system is somewhat more involved that this, but this should give you the general idea.

[mrlaser]

" Yep, that is not going to work well with a 6 v system"

EURIKA !!!

After months of wondering whether the engine would ever start, the thing fired up beautifully this morning. It turned out that the weak spark was due to a (2 actually) coil that I had purchased from a major early Ford supplier. When tested with a multi-meter across the positive and neg terminals they both measured 3.5 ohms. The 3rd coil, which was a NAPA, Echlin ,USA made product measured 1.5 ohms. This , unbeknownst to me , was the proper ohm reading. Anyway, I am pleased and relieved that things are now where they are. I appreciate the time everyone took to help me with this problem. Thank you.

[Bored&Stroked]

Glad you have it up and running . . . and I bet you learned a lot in the process. After all the time, effort and money - there is nothing like hearing it start for the first time! Now go drive it hard and get those rings to seat! Good luck and report back . . .

[Black Fifty]

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Good for you, Mr Laser! Fantastic news. I have been following along on your epic adventure. You should feel very good about your success.
Mike

[mrlaser]

Thanks. I have certainly learned a lot from the forum members. At times i felt rather discouraged, but took heart from the encouragement offered here. I also realize that others may be experiencing similar issues and benefit from the wealth of information supplied on this site. This is particularly true as fewer and fewer local mechanics familiar with the flathead engine are available locally.

B&S;

I will avoid running without varying loads. This, in spite of an overwhelming urge to "hear it one more time"

[Phil Gillespie]

A postive result where an actual faulty item was found, replaced with correct item and good result. logic progression and accurate fault finding.
beats the change out of several items at one time and crossing fingers and hoping for the best!
phil NZ

[Sid]

The parts man was probably thinking you were dealing with a 12 volt non resistor points ignition. That coil may be okay on 12 volt system. Just will not work with a 6 volt points type ignition.

[Roger W Gerow]

Re #12 above. Before any removal of parts I would try squirting regular motor oil in the cylinders first.-

[mrlaser]

I did do that very early on. It didn't result in an ignition. I actually did later squirt some assembly lube in each cylinder to temporarily boost compression.

[mrlaser]

The catolog image.

[Sid]

It just goes to show you that many of the parts suppliers and salesmen have no clue what they are selling. And if you ask them have they had any issues they play stupid and say they haven't. Just like JSeery stated earlier I don't think your car stood a chance of starting being a 6 volt with a 3.5 ohm coil.. If by chance it did start you wouldn't be happy with how it ran.

[mrlaser]

Actually, after going through some recent receipts, I found that one of the two coils with the high ohms reading (4.2 ohms in this case) came from a different supplier. After checking their website today, a 6 volt coil no longer appears when this part is searched for on the site.

[Bored&Stroked]

I'd surely talk to that supplier and inform them of the 'drama' that this whole wrong coil situation has caused you. They should at least take the coil back . . .

[Sid]

They should take back but we know they won't. It's electrical and been installed. What I can't understand is how someone can package a 4.2 ohm coil or even a 3.7 coil and say for a 6 volt system. You take it for granted that the manufacture and parts supplier have a clue of what they are selling. Also somewhere on the package the ohm rating should be shown. OHM rating is the most important thing to consider on coils especially with so many ignition systems available today and they all have the ohm preference they require. It was much easier 50 years ago when you basically had 1.5 ohm coils and 3.0 coils.

[mrlaser]

My main interest is to try to help others who may be experiencing similar issues. I'm still just ( kid in a candy store) happy that the problem has been solved. There were no specifications on the box or included in the box with the coil. The picture is of the top of the box. I did search the "B-12000 and found these coils in other supplier's catalogs. Incidentally, I did not purchase either coil from this source.

[Sid]

Sad part is that you could let these vendors know of your findings and they will still market these as a replacement early Ford coil and never research. Like you are talking to deaf ears or an illiterate. In the end it is the consumer that gets screwed. I've been there. If the car had happen to start it would not have run or start well and who knows how much you would have spent to find the problem especially with two wrong coils that you believed to be brand new and correct. It seems like quality and customer service are a thing of the past.

[JSeery]

When things come from China (the cheap stuff) there is no telling what you get. That is why you need to check. The other lesson is consider the suppliers you are purchasing this stuff from! Many of them are just in it to push parts and could care very little about quality or customer service. We have no one to blame except ourselves, there are venders who do care about quality AND customer service. A number of members here on the Barn provide quality parts, knowledge and service and are willing to help. When we learn to support those who care about the hobby this will stop.