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Is 180 psi in engine ok?


ebruns1

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Ok Fellas,

We just ran a pressure test in my 1958 D-24 project.  Not looking good.  Got about 30 psi in each cylinder (6 x 30 = 180 right?).  The car sat at least 20 yrs. but the engine did spin when I got it home.  My buddy pulled the head and found one or 2 valves stuck that he got loose.  New battery, points, condenser, head gasket, fuel and water pump, etc. installed.  Have spark.  Tried to start with some ether (gas tank not installed yet) and could not get any "pop".  Do you think the rings are stuck or is there any way to loosen them in the hope that I can start and run it as is?  I'd love to get this baby running and on the road any way possible!  Otherwise, I guess I'm looking at new rings at best, or a complete re-build at worst.  The car says 95K on the odometer and it looks like it!  Lots of floor pan and trunk rust through.  The PO just covered over them with sheet metal.  I'm not doing a frame off concourse resto...just looking to get back in running shape so I can drive while I slowly work on the sheet metal and other odds and ends.  Any thoughts on loosening up the rings?  PS - The cylinders were not scored when we had the head off, just a slight ridge at the top.  Any suggestions much appreciated!

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even with really low compression, with ether you should get something.  So I'd be checking for spark...  primary circuit, 12 to coil, points etc.  Points making and breaking circuit properly.  rotor, cap, wires and plugs.  If all that is good it should at least pop a few times. 

 

As stated Marvel Mystery Oil will help free the rings.  But, IMO a shot of ATF will work almost as well, especially with  50% acetone added. 

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You got my attention at 180 Psi. I was thinking per hole! 

 

When the head was off how did the cylinder walls look? Did you test for valve sealing? Maybe at least a good lapping of them all? Sure wouldn’t hurt. 

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14 hours ago, ebruns1 said:

The car sat at least 20 yrs. but the engine did spin when I got it home.  My buddy pulled the head and found one or 2 valves stuck that he got loose. 

 

Guess im confused. The rings are stuck but the engine spins?

Stuck in the piston grooves??

I think Keith had a good point since two valves were stuck. Be a good idea to test for valve sealing and use some lapping compound on them. An old trick for compression checks is to test each cylinder, write it down and then add just a spoonful of oil into the cylinder and recheck. A noticeable increase can show compression loss at the rings. 

 

Even so, even with low compression and a good spark should get something. 

 

Also I think when talking compression it’s more important to look at individual compression results for each cylinder. Not add them up. I thought it was 180 per also!

 

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