[KingLT1]

I didn't read all the posts so some of this has likely been mentioned.

-Failed lifter is usually collapsed and you wouldn't have any preload on the valve if that was the case. the push rod would move/spin freely.

-Valve issue would cause the symptoms you are having.

The LT1 heads are some what prone to valve issues. Pray now recommends the customer opt for fully worked stock castings with his heads/cam packages because of it. The LT1 heads flow great but they have valve issues like the LS7 stuff did. The only difference here is there seems to be less stock failures with the LT1 stuff compared to LS7. Once you increase lift, cam lobe intensity, seat pressure, and rpm, then this problem seems to show it's ugly head...it's almost always an exhaust valve too that bends or drops.

[cmitchell17]

Originally Posted by L78toLT1

Find a deep socket that is slightly smaller than the spring retainer, place it on the retainer and smack the hell out of it with a hammer. That will usually break the retainers loose.

Are you talking about the retainer or the locks? So are you saying to find a socket that's small enough to hit the locks? or the retainer?

[95 imp]

Originally Posted by cmitchell17

Are you talking about the retainer or the locks? So are you saying to find a socket that's small enough to hit the locks? or the retainer?

The retainer.

[cmitchell17]

I finally got it off after I bumped the valve from the bottom, but then I realized it was the exhaust side I just took off. So I tried the same thing on the intake side and it's not coming off.

If the valves had been floated (I also just raised my rev limiter a few weeks ago from 7200 rpms extreme fuel cut off to 7275 extreme cut off) that its what's making them harder to get off? I had to raise it to keep it from boucing off the rev limiter when it lost traction. I probably should have went the other way and just lowered my shift point.

The exhaust valve looked ok and slid in and out of the guide fine and didn't look bent.

If I keep hammering on this thing I feel like im going to break something.

[avalonandl]

Take the head to a good machine shop. You need to replace that cylinders valves, and if it were mine I would do all on the head.

Also lower your rev limiter to 6900. Thats pllenty with Hydr. rollers....

[Choda]

So the leak down showed #7 as not holding any air? And the head, valves and lifter look fine? I would say ringland then.

Im shocked you guessed on filling it with oil. You could have put half in, and checked the dip stick. Slow add and check oil level. 2+ qts is a lot.

[cmitchell17]

Originally Posted by Choda

So the leak down showed #7 as not holding any air? And the head, valves and lifter look fine? I would say ringland then.

Im shocked you guessed on filling it with oil. You could have put half in, and checked the dip stick. Slow add and check oil level. 2+ qts is a lot.

Yeah I got lazy with the oil, but I think I was just hoping it was becuase I overfilled it, in reality I think I have been revving it to high and just have too much cam with too much lift and its bent or somehow damaged the #7 intake valve.

I still can't get it off, even when I clamp the head down to the table where the intake valve is hitting the table top.

I would take it to a machine shop and have them at least check it, but being that I am away from home I don't know any good machine shops around here and don't want to take it to a random one and they end up taking 6 months haha, I mean I don't think that's very likely but I don't want my car to be sitting there that long. I guess I could ship them off but that costs hundreds in shipping cost.

Will heat do anything to loosen the keepers/locks?

[L78toLT1]

Originally Posted by cmitchell17

Are you talking about the retainer or the locks? So are you saying to find a socket that's small enough to hit the locks? or the retainer?

Use a socket slightly smaller that the retainer. Place the socket over the retainer and give it a good whack with a Hammer. The impact is enough to compress the spring & retainer a half inch or so and allow the keepers to fall off. Sometimes only one comes off and you need to smack it again.

[L78toLT1]

You can do a crude check to at least get an idea about the rings. I've seen big chunks of carbon buildup get sucked into the combination chamber, get smashed between the piston and head and compress the ring grooves enough to trap the rings.
What you do is position the suspect piston and any other random piston towards the bottom of the bore and pour in some thin oil, I have used ATF. If the piston or rings are damaged, the ATF will seep past much quicker than in the control piston

[cmitchell17]

Originally Posted by L78toLT1

Use a socket slightly smaller that the retainer. Place the socket over the retainer and give it a good whack with a Hammer. The impact is enough to compress the spring & retainer a half inch or so and allow the keepers to fall off. Sometimes only one comes off and you need to smack it again.

I tried it and they are just stuck in there, if my C clamp is big enough and I compress the valve at the combustion chamber and then stick a socket on the other end of the c clamp I am wondering if thats going to hurt anything? I mean the keepers/locks/whatever they are called have got to come out before the valve stem bends and buckles?

[cmitchell17]

Ok so I still can't get them off, but I just put the flashlight under the head and there is no light coming through, so the valve is sealing now?

So has anyone seen this before? Could it really have just been the valve seat clogged with something? I don't think so I still think I still have a bent valve maybe?

I mean if a valve was bent, it seems like it wouldn't open as easy as it does. If there was extra valve guide wear, it seems like it would still close and seat fully?

So maybe by beating and hammering on the springs it cleaned and lapped the seat and sealing surface off?

[cmitchell17]

Also I saw this, and this was only occuring in the #7 piston, the rest of the pistons looked ok.

I don't want to say this was detonation, because it seems to me it would be everywhere on the piston and not localized to only the outsides. Also I have run E85 basically 100% of the time, I do run quite lean but I run the same EQ ratio the GMPP LT535 crate motors run which is pretty lean which is 1.08 (which is 13.05:1 AFR on 100% gas) but this is the factory set calibration for the GMPP LT535 hot cam crate motor.

Anyway I don't know what else it could be but I don't think its coincidence it happened only on #7 and the valve also got messed up on #7?

[95 imp]

Flip the head so the CC in facing up and pour rubbing alcohol in the CC. If it is leaking into the port your still not seated.

The marks on the piston mean something has been banging in there.... Not good...

[cmitchell17]

Originally Posted by 95 imp

Flip the head so the CC in facing up and pour rubbing alcohol in the CC. If it is leaking into the port your still not seated.

The marks on the piston mean something has been banging in there.... Not good...

What do you think could have been banging? If eveything on the valve train is still intact and no marks of contact then what else could it have been?

So I tried bolting the head back up with just 6 bolts near the #7 cylinder and put the leak down tester back on it but I can't get it to seal it just blowing out, I guess that was a waste of time and ill have to pull the head off and do it with alcohol like you said.