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Old 09-23-2019, 04:33 PM   #1
mrlaser
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Default 8BA compression issues

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.?
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Old 09-23-2019, 04:45 PM   #2
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Default Re: 8BA compression issues

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
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Old 09-23-2019, 04:51 PM   #3
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Default Re: 8BA compression issues

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


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Old 09-23-2019, 04:56 PM   #4
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Default Re: 8BA compression issues

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
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Old 09-23-2019, 05:06 PM   #5
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Default Re: 8BA compression issues

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.
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Old 09-23-2019, 08:46 PM   #6
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Default Re: 8BA compression issues

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
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Old 09-23-2019, 08:49 PM   #7
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Default Re: 8BA compression issues

Also, the engine has never been started either in the car or on an engine stand.
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Old 09-24-2019, 07:03 AM   #8
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Default Re: 8BA compression issues

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.
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Old 09-24-2019, 07:22 AM   #9
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Default Re: 8BA compression issues

I'd suspect your valves aren't fully closing.
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Old 09-24-2019, 09:43 AM   #10
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Default Re: 8BA compression issues

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.
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Old 09-25-2019, 07:42 AM   #11
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Default Re: 8BA compression issues

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.
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Old 09-25-2019, 03:40 PM   #12
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Default Re: 8BA compression issues

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.
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Old 09-30-2019, 01:31 PM   #13
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Default Re: 8BA compression issues

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.
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Old 09-30-2019, 02:44 PM   #14
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Default Re: 8BA compression issues

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.
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Old 09-30-2019, 06:13 PM   #15
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Default Re: 8BA compression issues

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.
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Old 09-30-2019, 06:28 PM   #16
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Default Re: 8BA compression issues

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.
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Old 09-30-2019, 07:03 PM   #17
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Default Re: 8BA compression issues

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.
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Old 09-30-2019, 08:24 PM   #18
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Default Re: 8BA compression issues

Thank you all for the suggestions.
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Old 10-01-2019, 04:50 PM   #19
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Default Re: 8BA compression issues

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
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Old 10-03-2019, 06:07 AM   #20
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Default Re: 8BA compression issues

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.
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Old 10-03-2019, 04:56 PM   #21
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Default Re: 8BA compression issues

I have used regular "shop air"--160 lbs or so
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Old 10-16-2019, 06:05 PM   #22
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Default Re: 8BA compression issues

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?
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Old 10-16-2019, 07:54 PM   #23
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Default Re: 8BA compression issues

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....


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Old 10-16-2019, 10:51 PM   #24
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Default Re: 8BA compression issues

Thanks for the suggestions. I'll do that in the next day or two.
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Old 10-17-2019, 01:36 PM   #25
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Default Re: 8BA compression issues

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.
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Old 10-17-2019, 02:06 PM   #26
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Default Re: 8BA compression issues

Also, as suggested earlier, I will lap the valves.
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Old 10-17-2019, 07:48 PM   #27
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Default Re: 8BA compression issues

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Originally Posted by mrlaser View Post
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.
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Old 10-17-2019, 11:34 PM   #28
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Default Re: 8BA compression issues

Quote:
Originally Posted by mrlaser View Post
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.

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Old 10-17-2019, 11:39 PM   #29
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Default Re: 8BA compression issues

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.
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Old 10-18-2019, 07:08 AM   #30
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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!


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Old 10-19-2019, 08:44 AM   #31
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Default Re: 8BA compression issues

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.
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Old 10-19-2019, 08:46 AM   #32
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Default Re: 8BA compression issues

A 3 angle valve grind was done during the engine rebuild, but the valves were apparently not lapped.
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Old 10-19-2019, 10:15 AM   #33
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Default Re: 8BA compression issues

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
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Old 10-19-2019, 09:36 PM   #34
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Default Re: 8BA compression issues

Quote:
Originally Posted by cadillac512 View Post
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...

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Old 10-21-2019, 09:05 AM   #35
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Default Re: 8BA compression issues

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?
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Old 10-21-2019, 10:35 AM   #36
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Default Re: 8BA compression issues

I am referring to the spring compression tool rather than the keeper insertion tool. But, suggestions for both would be welcome.
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Old 10-23-2019, 04:09 PM   #37
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Default Re: 8BA compression issues

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.
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Old 10-23-2019, 04:12 PM   #38
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Default Re: 8BA compression issues

Another view.
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Old 10-24-2019, 06:48 AM   #39
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Default Re: 8BA compression issues

I did mine in a drill press.
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Old 10-24-2019, 07:15 AM   #40
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Default Re: 8BA compression issues

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!
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Old 10-24-2019, 07:16 AM   #41
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Default Re: 8BA compression issues

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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).
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Old 10-24-2019, 12:12 PM   #42
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Default Re: 8BA compression issues

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.
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Old 10-24-2019, 01:02 PM   #43
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Default Re: 8BA compression issues

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.
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Old 10-24-2019, 01:42 PM   #44
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Default Re: 8BA compression issues

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!
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Old 10-24-2019, 03:43 PM   #45
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Default Re: 8BA compression issues

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.
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Old 10-25-2019, 10:00 AM   #46
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Default Re: 8BA compression issues

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.
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Old 10-25-2019, 10:29 AM   #47
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Default Re: 8BA compression issues

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.
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Old 10-25-2019, 04:35 PM   #48
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Default Re: 8BA compression issues

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

Tommy
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Old 10-25-2019, 07:29 PM   #49
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Default Re: 8BA compression issues

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)
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Old 10-26-2019, 10:53 AM   #50
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Default Re: 8BA compression issues

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.
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Old 10-26-2019, 12:26 PM   #51
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Default Re: 8BA compression issues

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.
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Old 10-26-2019, 01:39 PM   #52
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Default Re: 8BA compression issues

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
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Old 10-26-2019, 05:21 PM   #53
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Will do. Thanks again.
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Old 11-08-2019, 11:19 AM   #54
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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.
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Old 11-08-2019, 11:24 AM   #55
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Default Re: 8BA compression issues

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.
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Old 11-08-2019, 11:28 AM   #56
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Default Re: 8BA compression issues

Were all of the intakes leaking?
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Old 11-08-2019, 11:38 AM   #57
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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.
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Old 11-08-2019, 11:44 AM   #58
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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.
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Old 11-08-2019, 01:01 PM   #59
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Default Re: 8BA compression issues

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.
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Old 11-08-2019, 02:09 PM   #60
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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.
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Old 11-08-2019, 02:25 PM   #61
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Sorry for the double post. I had to edit the picture size.
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Old 11-08-2019, 04:37 PM   #62
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Default Re: 8BA compression issues

can you look down the intake port and see if the stem goes that deep into the guide?
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Old 11-08-2019, 06:29 PM   #63
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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?
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Old 11-08-2019, 10:08 PM   #64
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Default Re: 8BA compression issues

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.
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Old 11-09-2019, 08:41 AM   #65
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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.
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Old 11-09-2019, 11:22 AM   #66
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Default Re: 8BA compression issues

Valve spring preload would be a factor if it's not long enough to firmly hold the valve on the seat.
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Old 11-09-2019, 11:28 AM   #67
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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.
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Old 11-09-2019, 12:25 PM   #68
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Default Re: 8BA compression issues

Quote:
Originally Posted by mrlaser View Post
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.
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Old 11-09-2019, 10:20 PM   #69
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Default Re: 8BA compression issues

Might be time for new block seats.
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Old 11-10-2019, 01:59 PM   #70
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Default Re: 8BA compression issues

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.
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Old 11-10-2019, 07:56 PM   #71
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Default Re: 8BA compression issues

You must use the proper retainers with those springs. There are 2 types of retainers.
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Old Yesterday, 07:41 AM   #72
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Default Re: 8BA compression issues

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