Hey guys, it's not an LS1 but same principles apply and you guys are smart. The engine is a brand new ZZ4 Chevy 350 ci. crate motor. We fired it for a couple of minutes, then it sat for 6 months. Today I tried starting it again and it locked up. I removed the spark plugs and coolant came out of 7 and 8. (not to mention i bent 3 pushrods trying to crank it initially) There is no coolant in the oil, so it isn't intake related? The only thing I could reason is a cracked head or bad head gasket. Any other ideas? I will pull the heads soon.
Your help is appreciated <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" /> , Ryan

 

I think your on the right track. Cracked head or bad gasket would be my first guess. How many miles? Did you recheck torque on everything before you fired it up the first time?

 

It was a new crate engine from GM. It was only fired once at the warehouse and then once again for 3mins. (no miles at all-just idle)
Next time I buy a crate, I think the torque on the heads is something I will definately check. I think the engine builder did not do this correctly.
Even though it isn't under waranty any longer, I received news that the dealership will look at it for me. I know the guy who owns the dealership, so I am hoping.
Thanks for the reply Greg, those were the only things I could think of that would cause this problem also (other than a cracked block, but that is iron...)
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" /> Ryan