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Discussion Starter #1
Looking at an engine that is barely running, misses horribly and sounds like it is out of time. I checked the timing and it is in time. I done a compression test and 7 of eight cylinders read at 180 pounds, one read at 150. The motor manual says the engine should be at 150.

What could cause this? It had a valve job done do you think they screwed something up on the exhaust valves (the springs are shimmed) or milled the heads without mentioning it?
 

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Proper tightening of the pushrods????
 

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Discussion Starter #4
Checked and double checked the rocker adjustment, and triple checked the cables, has new MSD cables on it and most all of the ignition has been replaced with new items, i checked most with the old parts and the same thing.

Father noticed that when the rockers are up you can push the lifters back down about 1/8-1/4 of an inch. He says that should not happen but I don't know enough about them to know, I do know the lifters are fairly new Federal Mogul (or Speed-Pro) cheapies.

I don't know I will jerk the head off today, maybe I have a bad gauge and 7 cylinders are right and one low but I really doubt the gauge is that far off.
 

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No they shouldn't .. but if he didn't pump up the lifters before install or preoil the engine before start up then the lifters will collapse until they pump themselves up ... then you have to reset the rockers which you probably have set too tight right now.. Which will give you all the symptoms your having seeing the valves won't close all the way once the lifters do pump up.


ShaZam
 

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Discussion Starter #9
Well at least it is something to look into, but I may put this vehicle in somebody elses hands. I did not expect to find the problem but he already knew that, still saves $60 hour on some mechanic poking around and doing the same thing.

Looks to me like the "new" valve seals are only on the intake and old ones are still on the exhaust it appears a small (very) amount of oil might be going through. Looks like crooks are everywhere these days, sigh. Also found that the silicone on the intake was not properly beaded all the way across and leaking. Also found a small piece of un-identified pot metal in the lifter valley, obviously a piece of the heads as I can see nothing else that could have got there.
 

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I'll take a wild azzed guess and say you're looking in the wrong place. I'll bet on an electrical problem not related to the mechanical repair. Maybe somebody pinched or stretched a wire bundle...
 

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Discussion Starter #12
Yes but the wries have been checked, my last guesses are either the electronic spark control, computer. Other then the knock sensor all of the rest of the electronics are new.

I can read proper voltages/resistance everywhere. I agree mechanics seems to not be the problem and I felt electronics was likely the issue even before. The low cylinder was the big confusion there and likely the lifters needed replaced regardless.

I won't suggest any more purchases however, because I can take no responsiblilty for money wasted.
 
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