Taking pistons out the top with engine in truck - 1500

[DacotaKid]

So long story short replaced cam / lifters timing chain water pump...other few items...to get rid of lifter tik. Cam lobe on cyl 3 was worn down very bad. Forgot to torque the cam bo;t so it spun and bent some valves / pushrods.

Tore it back down. Took heads to a great machine shop. they rworked everything. Did a great job. Put it all back togather. Cranked right up. Ran very well. Got it up to temprature and started hearing a missfire. Got continually worse. Got misfire on cyl 3 along with random missfires. Checked compression. 0 compression on #s 1 and 3 cylinders.

Removed driverside head. Looked great. Pistons lookes good. No crosshatch in any cylinder but no ridge at to to speak of. Re installed head without pushrods and lifters and rechecked compression.

No compression. poured in some Lucas oil and retested. Compression jumped right up, so looks like the rings got blown out maybe due to the heads being reworked with some new valves and all other rseated along with valve guides knerled except two that were rplaced.

so we're gonna remove the pistons out the top and rering, hone enough to take off the glaze being extra careful to keep everything clean.

Anyone pulled the pistons out the top with the engine in the truck? Got a set of clevite rodbearins and mahale rings arriving by tonight.

 

[DacotaKid]

 

[DacotaKid]

It'd down to the bare block right now. We're ready for the rings and bearings to do 1 piston at a time. So the pic's above are while we were working on it.

 

[Yardbird]

The low compression problem could have been nothing but the cylinders washed down with gas. You should have tried starting it after putting oil in the cylinder.

I have bought a car that had zero compression on all 4 cylinders. The fuel injection had hung open and flooded the engine.

Fixed the injection, put oil in the cylinders, spun it over several times, reinstalled plugs, and it ran like new.

I said all that to say this, the teardown should have waited until you checked farther. With the compression coming back up with oil in the cylinder, everything was probably OK at that point

I know it's too late now, but maybe this will help you or someone reading it before going deeper without completely checking everything.

I've dug myself way deeper into a hole than necessary from not doing one more easy step before tearing apart.

 

[DacotaKid]

We've had the heads off twice on this motor. I didn't believe it lost compression while running after all the crap we went thru...but we're now debating on removing the engine as opposed to doing it installed. Joked about the rear main seal will go out if we don't replace it....gonna start back on it tuesday or wednesday. The injectors and fuel seemed fine. I do appreciate the resposne.