Replacing Blown Motor, 5.7... suggestions?

Schurkey said:

I would have tried a cranking compression test, and a cylinder leakdown test BEFORE removing the cylinder head.

If you tap (not "beat") the "short" valve with a plastic-tip hammer, does it move, or is it jammed in place?

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It is jammed in place. I removed the nut that holds the lifting rod and it didn't budge. Engine sounded terrible, with a loud knock. I don't have a compression tester and never even heard of a leak down test (novice here)... sorry guys I wish I could say I was more mechanically inclined but I'm not.

GoToGuy said:

Why is it not at full height ? Broken valve spring - loose spring, valve stem bent jammed in guide- compressed valve spring. Short spring- valve face bent not seating. You just had misfire, any knocking, no oil pressure issues?

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No oil pressure issues, although, these oil pressure gauges are crap I've been told. BAD knock, have to keep on the gas pedal just to get it on and off the trailer. Current status is I have drained the oil, the coolant, and removed wiring harness and both valve covers. Other side of engine looks good, no stuck springs or short springs. Thinking if I remove the head I will see the stuck valve and either replace it or free it... or worse and replace the motor.

I just looked at your picture of the rocker on the "short" vale stem. Sorry that I didn't previously. The rocker has been tightened far too much and has almost certainly collapsed the lifter. You can tell by how much thread is above the nut compared to it's neighbors. If you remove the rocker you can see if the spring closes the valve or not. But you have issues to be sure that were caused by somebody haphazardly working on the valve train.

JeremyNH said:

I just looked at your picture of the rocker on the "short" vale stem. Sorry that I didn't previously. The rocker has been tightened far too much and has almost certainly collapsed the lifter. You can tell by how much thread is above the nut compared to it's neighbors. If you remove the rocker you can see if the spring closes the valve or not. But you have issues to be sure that were caused by somebody haphazardly working on the valve train.

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Well, that nut was tightened down by yours truly so I will back it off for sure, but it never ran with it that tight. I removed that nut to take the rod out and inspect and the spring did not release at all. It is stuck in that position. I know nothing of lifters or springs so thats why I tightened it down, was just trying to make it the same feel as all the others but... now I know that the spring is too depressed and thus the nut is too tight for when the spring needs to release. Thanks for the help guys. Honestly, I wish I could shake your hands. I really appreciate it.

Okay tough love time. If your not familiar or trained on certain mechanical systems or their operation, you really are out of depth here. Brutal honesty. Did you mention the knocking condition before? Do you know the diff' between preignition pinging and bearing knock? Do you have access to borescope or one of those that hookup to your smartphone? This is perfect opportunity to look through the spark plug hole and see whats going on with the valve seat and top of piston.
I reveiwed, you never mentioned the knock. That makes this a whole new problem. Most likely a terminal condition, verified by pulling the head with the valve condition and possible piston damage. Results of that visual will determine next steps. Good luck!

Why would somebody who admittedly and repeatedly say he’s not a mechanic and knows very little as an auto mechanic have a bore scope?

I dont even have a bore scope in my shop full of tools. those some beaches are expensive!

NW4x4Chevy98 said:

It started with a cylinder 3 misfire code. Accelerating up a hill started a heavy knocking and when I pulled over it completely died. Trailered back to the house, it won't stay running under its own power. Sounds terrible. So I removed the valve cover and the only thing I could see thus far was one of the rods and lifter was extremely loose, flopping around... pulled the rod, checked to see if it was bent, no bends that I could see even rolling on a flat surface. So I was told the best thing to do is remove the head, which... is a lot for me. No shop... snowing... the whole 9. But I have started the process of removing the heads to see if it is a stuck valve. Or worse... sound proper?

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Already mentioned the knocking. I'm good with tough love, like I said I'm way out of my elements here, hence the post and request for suggestions. No bore scope. I could probably purchase one. Should do that. But again, not a mechanic and there aren't many around that do good work in my area. Just a working guy thats trying to fix his truck by himself... I appreciate your continued attention to this thread and I don't take it personally, doing the best I can.

Borescopes are no longer the luxury of medicine(orthoscope) or aircraft engines. There dirt cheap technology now. Kids have them. Home repair. Inspection. How the hell would i know or not know whats in everybodies toolbox? You want answers ? Later, merry christmas.

that's hilarious. sure they are not as crazy expensive as they used to be but they are still not cheap. if your someone who is going to use on once a month, hell buy it. once a year or less? I'll put my money elsewhere.

I buy tools as I need them. I have a transmission jack and have used it 8 times in the 10 years Iv owned it. people tried to talk me out of buying it... well if your going to drop a tranny, you need the right tools or someone is going to get hurt.

fixing this motor was never a part of the OP's question. so he doesn't need a borescope. your just giving out advise no one asked for, just like your famous for.