I take it you had the oil pump and timing set off? Did re use same woodruff key on the crank? Check your cam/crank alignment to each other? if you get the plugs out and the valve covers off and roll through the firing order with a breaker bar you may see what went wrong.

 

UPDATE

Today I took the valve covers off, all the springs look in perfect condition they are .650" prc dual springs. rockers have no pay at all. Took the spark plugs off and turn the engine by hand, and there is an interference every 1/4 of a turn, it gets very hard to turn for a moment then it continues really smooth. I remove all the valvetrain and turn the engine engine and it turns very smooth no interference, So I think the problem is in the heads valves. Gonna try to take them off in the next days.

 

sorry to hear about that! hope its an easy fix for you..

 

Dang that sucks. There is obviously something in one of those cylinders. If you removed all the pressure off the rockers and no valves are sitting lower than the others, something got in there one way or another which you were seeing the interference when you were turning over with rockers on.

 

Yesterday I received the pushrod length check tool, I put cylinder #1 at TDC and measure and it gave me 10 turns so I did Im at 7.300 length at zero lash, How much preload would be good for the ls7 lifters, .081"?


I gonna take the heads off tomorrow and found out how bit is my problem.

 

Did you check timing gear bolts? Maybe they are backing out. Hope you find out

 

what do you mean by backing out, I haven't check them

 

No need to pull the heads yet. Loosen or remove all the rockers. Spin the engine over by hand. It should rotate freely without any binding. If it does NOT, forget about PTV issues. You have a problem with the shortblock. If it turns over OK, then pull the cylinder heads.

 

I loose the rockers and it turns freely with no interference, So for sure there is something wrong with the heads

 

Sorry to hear about your bad luck. I'm I'm the middle of a cam swap myself and wasn't planning on checking my pushrod length since I'm staying with stock heads and lifters . But now I'm having a change of heart.

 

Tell me about it , check everything twice to avoid this!!!

 

Hardened pushrods??? or did you use the OEM 7.4s?? Maybe you bent one or maybe bent a valve.

 

I took the heads off today and found the problem, 3 lifters collapse, one of the is stuck in cylinder # 2 the exhaust one, here are some pictures of the damage, the cam looks scratch really bad, in cylinder #6.





Heads are in good condition



I think the cam is done, Im gonna take it off tomorrow. So this is what happens when you don't measure your pushrod length !!! the only good thing about it, is that it wasn't a head valve or a broke cylinder, or a bearing.

 

what thickness head gasket did you go with?

 

I got the GM LS1 MLS Head Gaskets that are .054" thickness

 

sub'd for pics of scratched cam, btw are you some kind of teleporter? How do you have an update from 10-27-2013??? I hope all goes well.

 

LOL I didn't realize that, Im getting the cam out tonight, I will post pics of the damage.

 

Damit. Sorry about the bad luck. This is without a doubt the fault of a pushrod that was too long? You didnt miss any shifts beating on it or anything?

 

Are the cam bolts loose? Did you locktite them?

 

[QUOTE=leeluther252;17267790]Are the cam bolts loose? Did you locktite them?[/QUOTE

I didnt put locktite on them, torque them to specs and they dont seem to be loose