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Frankenmotor problem - dead cylinder - No compression #3

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Block 97 EJ25D

Everthing else is 95 EJ22E

Cometic HGs

Delta Cams

 

Worked one night, but not the next morning.  It was running hot and probably detonated.  Has spark and gas but no compression.  I pulled the head and isn't apparently evident why there is no compression.  Exhaust valves are much darker on 3 than 1.

 

Zerocomp007_zps48206b21.jpg

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Dry the head thoroughly.

 

Set the head with the exhaust ports up. and fill the exhaust chamber with brake clean, or mineral spirits, or carb cleaner or whatever.  Some thin solvent.

 

Watch the valve area (combustion chamber side) for any signs of leakage past the valves.

 

Leave it overnight, 90 percent of the liquid should still be there, and no signs of wetness past the valves.

 

If the exhaust pass, repeat for the intake valves.

 

If the valves pass, inspect the headgasket again for any signs it had failed and was no holding compression.  If that is good, then suspect the piston.

 

pull the engine, the seperator plate, and then pull the wrist pin and piston for #3.

Edited by Gloyale

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I've had the hydraulic lifters pump up too much and hang the valves open. Check the drain ports on the rocker arms for obstruction, also remove and clean the lifters.

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Dry the head thoroughly.

 

Set the head with the exhaust ports up. and fill the exhaust chamber with brake clean, or mineral spirits, or carb cleaner or whatever.  Some thin solvent.

 

Watch the valve area (combustion chamber side) for any signs of leakage past the valves.

 

Leave it overnight, 90 percent of the liquid should still be there, and no signs of wetness past the valves.

You nailed it again!  It just started pouring out of the exhaust valves.  I wipe it dry and the combustion chamber is covered again in 15 or 20 seconds.  Looks bad enough to produce 0 compression, I would think.  Thanks again Dan.  I'll probably run out to pnp and grab a head tomorrow.  $50 w/o cam.  Hopefully I can get out of this pretty cheap.

 

So what, I just overheated those springs and they weakened and can't keep the valve closed anymore?

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Don't forget to tighten the lower engine stud nut when  you are all done.  :rolleyes:

 

If you don't find a good head I have a set in Colorado Springs.  Larry

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Hlas stuck wide open relase the oil preshure by removing hla and pushing in the ball on bottom and pumping the oil out at same time then can start with them down all the way and let them addjust

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That's a simple check really. Just remove the rocker arm assembly from the head and recheck the leaking valves.

Might want to compress the springs a bit and make sure nothing is wedged in the valve seats (carbon/crud).

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Did you pull the valves to see what the problem was ? bent ?

They didn't appear bent or damaged in any way.  Looks like the springs just couldn't keep them completely closed

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