No compression

By jumping into tearing it down, you have already made the problem harder to diagnose.

The first thing to do when it won't start, is listen. If it turns over with a normal cranking sound, you probably have compression. In that case, go look at spark and fuel.

If it spins over and a higher than normal speed, and sounds like it spins freely, you probably have a compression issue. In this case, pull the distributor cap of and watch the rotor while cranking it. If the rotor is not spinning, you probably have lost some timing gear teeth. Now is the first time I'd consider pulling out any tool, and that tool would be a compression gauge.

If you measure no compression on all or most cylinders, it's time to pull the timing gear side cover, and carefully watch the teeth on the cam gear, while cranking it over with a hand crank. It will take to full revolutions of the crankshaft to see all the teeth, so go slow, and make sure when you turn the crank, that the timing gear is actually turning too. ( If you don't watch the fiber gear turn, you may just see teeth after each crank, because you are looking at the same teeth!)

If all this checks out, only now would I remove any other engine parts. ONLY AFTER ALL THESE CHECKS, WOULD YOU REMOVE ANY OTHER ENGINE PARTS!
 
Was the starter actually engaging the flywheel? Easier to check the starter than it is to pull a head. Bendix May just be spinning which may make it appear there’s no compression. An actual compression test would’ve been step 1 with readings on all 4 cylinders.


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I agree that PERHAPS pulling the head was a bit premature without first running a couple other checks (compression, distributor shaft rotation, starter operation), but the situation as it stands now is not without an advantage. With the head off, the OP can push the starter rod and check the operation of ALL the valves, as well as whether the starter actually turns the engine over. It's highly unlikely that between the time the OP parked the car in the barn and when he went out the next day to start it that at least one valve in each cylinder became stuck, a couple valve springs broke or that the head gasket blew out in each cylinder. Pushing the starter rod when the head was still in place would have told him whether the timing gear was stripped, the head gasket had blown and/or whether the Bendix drive was inoperative In all three cases, the starter would have turned the engine over at a noticeably faster rate than usual, which the car's owner should have recognized by the difference in sound. One poster already suggested this. Too late in this case, but a good sleuthing method to keep in mind for future problems of a similar nature.
If the valves open and close through a few revolutions with the starter, the OP can observe their operation and eliminate stuck valves from the equation. If only a few valves open and close as they should, but others remain stuck open, then there is a problem possibly with them sticking in the guides. If they don't move at all, the timing gear is stripped or possibly the oil pump drive gear is stripped or the shaft's pin sheared off. Easy to spot this by re-inserting the lower distributor shaft into the engine (assuming there is the two-piece shaft in place) and push the starter rod. If the lower distributor shaft doesn't turn, then we're back to a stripped timing gear or a problem with the oil pump drive. You could also just look down onto the distributor shaft hole and see if the oil pump drive gear is turning. That requires more gymnastic ability while holding down the starter rod than watching the lower shaft turning above the deck of the block.
If the starter spins, but the pistons don't go up and down, the starter's Bendix spring is either broken or a drive mounting bolt has sheared. Easy to check this operation.
If all the above work o.k., then about the only thing left to explain zero compression is a blown head gasket, unlikely as that would be. But all four cylinders blowing out - while the car is parked? I'm leaning more towards a stripped timing gear/oil pump drive or trouble with the Bendix. Pistons go up and down, the valves operate fine = what else could explain zero compression - if a zero compression situation actually did exist and the signs were not misinterpreted?
Marshall
 
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egm said:
Thought gas was bad, rebuilt carb no go, checked compression 0 at all 4
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Bad gas or no gas, new carb, rebuilt or whatever has nothing to do with the loss of compression. Me thinks a good review of 4 stroke engine operation is in order. Post 17 & 26 explains it all, there HAS to be some compression in at least 1 cylinder.

John
 
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Czee said:
Thats your opinion!
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Your right. What I meant to write is "You really do NEED to read the whole thread". I think you missed part of it... :p:p He stated in post #7 the valves are "moving up and down" (opening and closing) so that kind of shows the engine was turning over.
 
Whats the deal here? Is egm the O.P. and Czee with the problem? Nothing makes sense with this thread or the alleged problem. :confused:

John
 
Y-Blockhead said:
See post #7... Distributor lifting??
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What I meant to ask was,
Are the valves lifting when using the starter?
Are the valves lifting when using the hand crank?
Is the distributor turning when using the starter?
Is the distributor turning when using a hand crank?

The OP hasn't posted in over a day to simple questions.
 
There have been so many condescending responses I'd be surprised if the OP hasn't just left the site in disgust. However, I agree there is something strange going on with his engine. Obviously more to the story.
 
eagle said:
There have been so many condescending responses I'd be surprised if the OP hasn't just left the site in disgust. However, I agree there is something strange going on with his engine. Obviously more to the story.
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I really don't see any condescending responses to the O.P. and sincerely believe everyone was trying to help. Now we have a new member who joined within the past couple hours tossing in a 1st post that doesn't make sense in context with previous posts. I agree something strange is going on - maybe not with the motor.

John
 
Removed in.ex. Manifold valves very sluggish, intake ports heavy layer of black tar. Bad gas? Have used start bill since new valves maybe try marvel or sea foam next. Well have to clean up the mess thanks for the help
 
egm said:
Removed in.ex. Manifold valves very sluggish, intake ports heavy layer of black tar. Bad gas? Have used start bill since new valves maybe try marvel or sea foam next. Well have to clean up the mess thanks for the help
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That finally makes sense. Thanks for the update.
 
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