At one point you said you pulled the valve covers to inspect for problems - I never followed up but I thought you’d have mentioned it if you found something.

An easy way to check for sure would be to perform a leak down test. There is a specific tester for leak testing (might be available for rent at a local parts house) but if you can adapt an air hose to your compression tester that will work as well. Given the extremely low compression, I’d recommend regulating the air to less than 30 PSI to start, then slowly increase it if you don’t hear anything.

Put #3 at TDC compression. Remove the oil fill cap and radiator cap. Supply air into the cylinder via the spark plug hole, then listen for air escaping at the oil fill, throttle body (open plates), look for bubbles in the radiator (or listen for air at the radiator if the system is empty), and at the tail pipe.

Depending on where you hear it will determine the likely cause. Keep in mind you may hear it from more than one location.

Oil fill = crankcase = rings or hole in piston
Throttle body = intake = valve
Exhaust = valve
Radiator = head gasket

As for methods of repair, if you don’t have a way to pull the engine (assuming rings are the cause), the easiest way will be to get it on jack stands. The front diff will have to come out to drop the oil pan, but the crank can be rotated to allow the piston to be removed without actually removing the crank. It’s time consuming but do-able.

I’ll let you know on the rings. I’m not sure which rings are recommended in this situation.

 

I am going to build a leak down tester to verify valve operation.etc

 

Lol I didnt see your post until after I wrote my last post. Makes sense not to assume and test. Appreciate all the pointers

 

I built a vac tester and I have air coming out of tbi plates and you can hear it major when i open them at 30 psi. I tried both tdc just to be sure and you can clearly hear it.

 

Time for head removal and inspection. Hopefully it’s just burned and not stuck.

 

I can definitely see what looks like a weld carbon puddle

 

Yeah that’ll do it. Is it built up more on the port side?

I’d suggest just trying to clean it up and reassemble but you have to answer the question of how it formed in the first place. A machine shop could crack check it and resurface, but if you’re gonna take one head in, my opinion is to take them both.

 

I wonder if it came from idling long periods. He would idle the truck for 3hrs lots.

 

I think it is snake skin or cockroach?

 

Now i can clearly see the problem