What's up guys? I recently purchased a 1999 LS1 for my 240sx and I had a few simple questions that maybe someone could help with. I've got a good amount of mechanical experience, but none directly with Chevy. I've taken push rod dodge v8 engines apart and understand the concept, but its always nice to have direct experience with a motor.

Anyway, I pulled the motor out and inspected it before installing the custom oil pan and mount kit for my car. It looks to have a few small leaks.

1. Where do you think this oil leak is from? It looks to be around the cam sensor or oil pressure sending unit. The o-ring on the cam sensor looks to be okay, but there is plenty of oil puddled up on the back of the motor. THe rear main sean and cover look to be sealed fine. I am guessing either valley cover, oil pressure unit, or cam sensor. Here is a picture:



Also, here is a picture of the sensors.



2. Everything else looks good, but there is a small amount of oil on the front behind the water pump. The front main seal looks fine, but maybe the cover is leaking?





3. The engine has 110k miles on it. I am at the point where I can pull the heads pretty easily. Should I replace the head gaskets just because I'm already in here? They seem to be fine and I've heard the engine run, but I was thinking as preventative maintenance to do it while its on a stand. Any advice? How long do stock gaskets usually last?

4. I've read about the car starter failure and block cracking issue. I want to upgrade to a truck starter, but wasn't sure about compatibility. Any specific year, make, model? Or will any LQ4 4L60E starter work?

5. Upon removing my valley cover I broke one of the knock sensor top plastics because it was seized onto the electrical clip. It looks like it will still fit fine, but the white plastic tip piece is missing a chunk. Does this need to be replaced? I don't have a picture, but I can get one.

Thanks guys!

 

my guess would be valley cover and front timing cover gaskets (and/or front main). pretty cheap to replace.

as far as head gaskets, theyre generally only designed to be compressed once. some guys spray them with copper and run them again, but at 110k miles I'd replace them. especially since they aren't that expensive (assuming you're using the stock MLS ones).

can't really speak to the other things. good luck with the swap