LS1TA76

Straight to the point. So we had a leaky water pump on our 1996 C4 LT1, and we replaced it, the car used to run at 189 degrees and after the swap it ran at 193, the problem was that the coolent was boiling and steam was coming out from the cap and the overflow tank. Even with the car steaming the temperature remained at 193 degrees and did not changed. So we replaced the cap and still the same problem, coolent boils and steam from the cap. So i parked it, the next day my brother toop the car for a spin and it started to smoke with the twiking sound (belt like) from the back of the engine. While the coolent temp says 193 even with bearly any water left and oil temp got to 280 degrees!

so here's the problems now:
1- the car vibrates at idle
2- when cranking the engine the starter slows down at one point (grips) and keep griping at the same point until it starts.
3- twiking sound from the very far back of the engine.
4- water still boiling.

So i suspect blowen head gasket.. but the cranking grip made think it spun a bearing.

Any ideas?

Thank you

pdxmotorhead

Time to pull it and tear it down.. Hot engines don't get better driving them..

If you want to prove its got issues you can pressure thest the system, or put a bore scope in the cylinders and check for antifreeze.
The bore cameras are available cheap on EBAY that plug in to a smart phone,, absolutely a useful tool for the toolbox..

SS RRR

iTrader: (2)

If coolant was boiling over there was air in the system. There is a specific way the system needs to be bled because of the reverse cooling. As stated, if the engine is not running like it was before these problems happened there's a good chance it over heated and bearings could be shot. Hard to accurately diagnose on the internet.

BALLSS

Op

if you didn't, bleed the air from cooling system next time. LT1 is a reverse cooling motor