Cars like to run warm i guess?

[04_Sport_LS]

still running hot\fluctuating greatly,

That right there tells me there is air in the system. Shouldn't be any fluctuation in coolant temp.

 

[04_Sport_LS]

Dare I suggest that you have a head gasket leak... bad head, or a cracked block. That would explain all the Stop Leak.

 

[04_Sport_LS]

Some previous owner may have run straight water in it, and when a cold snap hit, the block froze.

I do realize that it gets cold in Nevada at night. Especially in the winter.

 

[SultanGris]

Yes, like I said this thread is 2 years old, that motor blew up, waiting for a newer one to be installed, hopefully solves all my problems, cars been sitting for 2 years. First motor they sent was no good, they dropped and broke the second one and mechanic just got the 3rd one so hopefully it's good and fixed within the next month or two.

 

[nghtshd88]

Went to put a new OEM thermastat in and fixed half of my running warmer issue on the new donor motor. Piece of plastic tab was lodged in the thermastat. Maybe it was laying in the donor motor.

About to compare the old OEM pump still on the old motor vs the new aftermarket pump that I have on the donor motor this week.

Manual says thermastat housing must come off to change the water pump. If thats really true I probably will live with it. Not looking to take that off again anytime soon..

 

[04_Sport_LS]

Yes... the tabs break off, but they are just for centering.

If you have a Gen 2 3.9... the water pump is the easiest thing to replace on the LS.