I would see if you could get a hold of a borescope and take a look inside of the cylinder and get a look at the piston. but if you have air coming from your crankcase with the valves closed, it sounds like ring problems.

 

ive already dont compressoin test it measures 80 psi while normal pressure is around 125. also a leak down test would do me no good cuz the air leaks out through the crankcase as fast as i put it in. and... i went to my mechanic to use his boroscope, and it stopped workin correctly! it was all blurry. I plan to take everything off this weekend to see whats up. there are others with the same exact prolem. i hope i can help them out.

 

It looks like you have the perfect excuse to swap in a 6.0 and a nice cam.

 

im not buying a blown piston or rings for the simple fact i got 4 cylinders running 80 psi.. what are the chances? and to top it off,, they are paired up! also,, what are the chances a gasket blew inbewteen both cylinders? but how much more unlikely would 4 pistons or rings be blown instead!? the odds are in favor of a gasket problem i think.

 

You think it might be leaking into the area where the lifter retainers are?

 

could be. Ill find out for sure hopefully saturday. You should of seen the look on the head tech. at teh chevy dealership today when i drove in and showed him my truck. then told him all teh probs it has. i didnt have a clue as to what the prop could be.

 

LOL .. Where'd you go?

I always take mine to Alford's in Jefferson.
There's a guy named Matt there, he seems to know his ****.

 

It's a cracked ringland on #7 for sure. When you pull the head, it will not be pretty.
6.0L Time -don't detonate, it will tear a boosted motor up in seconds.

 

Sounds like the voice of experience ....

 

Actually I was just thinking about it, and I would not want to put a "for sure" on anything I cannot be there to hear. When I do valve spring swaps, I load the cylinder with compressed air so the valves won't fall. Well, you hear the same air leaking noise. And, yes, it is because it leaks past the rings and into the crankcase. And where does it vent...that's right the hose you have in the picture.
I would get a leakdown test to be sure, but I am almost willing to bet there is damage to some pistons too.