8BA engine

[whatdoyouwant]

Hey guys, I have an 8ba engine that has been setting several years. I can start it up, but runs terrible. I checked compression and I have 0 pounds on number 5,6,7. All the rest are at or over 100 pounds. I think the valves might be stuck because of just setting. Is there any way to free them without pulling the head. I can if I must, but am looking for something easier.

al

[marko39]

I’d pulled the head as you really should see what’s happening in those three cylinders.8ba is easier than the earlier ones as it has bolts instead of studs.

[cas3]

I have had good luck by soaking them in your favorite juice, and then reach in with an allen wrench and tap them down, turn the motor to get them up again, etc, repeat as necessary. Try to hit the center of the valve, not too violent. Might check to see if you have a mouse house in the intake too

[flathead4rd]

Pull the driverside side head. Thats where 5 6 & 7 are located. Agree it sounds like stuck valves.

[big job]

I can whip the intake off with a zip gun 20 sec., then fight with generator and fan 1 hr LOL BUT with intake removed now you can really see things valves stuck up gently tap down on valve springs and snake oil, its usually the valve guide / stem gummed up and a little rust on top of the guide. Fact is all side valve engines do get stuck caused / humid and moisture conditions ..........

[whatdoyouwant]

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OK, I pulled the left head and can tap the valves closed but I can't find anybody small enough to stay inside and keep taping the valves. I guess next I will pull the intake and see what I can do. The engine was only run 3 hours on a test stand years ago. Do you think I need to pull the valves and lap them? It does have adjustable lifters and I have never taken the valves out of a flathead engine.

[cas3]

If you have a starter on the engine, remove all the spark plugs, spin it over, and keep oiling it up and tapping them down until they go down by themselves.

[mfirth]

Use some Marvel Mystery Oil in the mix.

[whatdoyouwant]

Got the head off and am working the three valves with panther pee. They are getting better, so maybe that is as far as I will need to go for a fix.

[whatdoyouwant]

Well, I have tried freeing the valves for three days with only a little success. I have now pulled the intake and can see that the lifters are going down but the valves don't go all the way shut. I guess I will now pull out those valves and see if I can clean them and the guides.

al

[cas3]

Keep them in order !

[whatdoyouwant]

Well, bad news. I got the valves out and they are bent. I think now that I have a problem with the heads. I have a JR400 cam and 8BA heads. Could that be the problem? I don't know why only those three cylinders, but the valves must be coming up and hitting the heads. What do I need to do? The engine is in the car, so I don't want to change cams at this point. Are there other heads, or can I have these machined to fit? I don't know what to do at this point.

al

[Karl Wolf]

Some one may have done a compression test with a tester that was too long.
Valves get bent when the valve opens fully.

Karl

[tubman]

Are there any "witness marks" on the head where the valve may have hit? 8BA heads should have plenty of clearance. However, who knows what have have been done to them over the interim.

[whatdoyouwant]

I don't really see anything on the heads, but after bending they probably don't hit any more. Can I measure the distance from the block to the top of the valve when it is open, and then measure from the surface of the head to the valve cutout, and add a gasket thickness? Would that tell me anything?

al

[cadillac512]

First thing I'd do is install a head with a couple bolts left loose...maybe 1/8 " loose. Then rotate the engine and see if the valves lift the head with and without a gasket.

[whatdoyouwant]

Has anyone ever put two head gaskets on to solve this problem? Just a thought

[tubman]

Don't do it. Iron heads are cheap and easily available. Just check them before you bolt 'em down (foil balls or clay).

Late model heads are probably a lot cheaper than a new set of gaskets the way prices are these days.

[whatdoyouwant]

OK double head gaskets areout

[Seth Swoboda]

Originally Posted by whatdoyouwant

Has anyone ever put two head gaskets on to solve this problem? Just a thought

Not me personally, however I know it has been done and worked. Did you deck the block when the engine was built? Did someone remove too much material?