lsfanatic

What does everyone do to check and see if a used motor you have is any good? I have a used LS1 I got in another deal, and I want to swap it into another vehicle but don't want to put it in just to find out it has a spun rod bearing or something. I can't think of anyway to check without tearing it apart, and at that point you might as well rebuild it (not something I want to get into if I don't have too; just want to get the car running).

My thought is I should just try to start in on a stand and see if it runs okay. I have a wiring harness and a PCM but its my understanding they won't run the engine standalone without the security stuff removed. What are your thoughts? Thanks

allmotor1

Compression and /or leakdown tests will tell you a lot with out having to take it apart

lsfanatic

That's a good idea. Won't really tell me anything in terms of bearing condition though right?

LLLosingit

iTrader: (4)

Bad bearings almost always mean low oil pressure. You could hook up the starter and pull the plugs and hook up a mechanical oil pressure gauge and spin it over and see how it build oil pressure. Leak down test will tell you everything you need to know as far as ring/valve sealing condition.
If it still has the oil filter on it you could cut it open and look for bearing debris.

lsfanatic

That is a good point. No oil filter unfortunately. So between checking oil pressure build and leak down that pretty much covers the bases for what you can do without firing it off?

RockinWs6

Pull the oil pan and look around, if bearings are worn you will see signs of copper laying around and other shinny particles. You can also look for discolored bearing caps etc and move the rods a bit. You can feel worn loose ones. Also you can see the thrust bearing surface and the cam and cam bearings. Get a look at the cylinder walls without pulling off the heads too.

MuhThugga

Not really.

You can easily pull a few main and rod caps, inspect, and torque back down. The motor is already out and on a stand. Flip that bitch over, pull the oil pan, and take a look.

lsfanatic

That is a good point, I forgot the windage tray is not bolted under the main bolts.

Most of the motor work I have done in the past has been Northstar stuff, and with the split block and the windage tray under the main bolts you can't check anything without pulling the bottom end apart completely.
I have always been told you can't reuse rod bearings?

Though I did think about changing out the rod bolts so maybe I should do that anyway.