Just replaced the 190* t-stat in my 93 JGC with 229,000 miles. Old one opened at the right temp, but not all the way. So, while repairing a gasket leak, I opted to buy the stant part w/ 1 yr warranty (the least-cost stat, as opposed to lifetime warranty).
Once replaced, engine temp quickly rises to ~195, then slams down to 170. Then up to 195, slams down to 170. All day long.
Now, the h20 pump was leaking, so I just had it replaced. The new pump has slightly changed things... Does this now:
- warm afternoon: engine temp quickly rises to ~195, then slams down to 170. 195, 170, up to 200, stays put.
- chilly morning: engine temp quickly rises to ~195, then slams down to 170. 200, 170, up to 210... and keeps bouncing.
It cycles 2-3 times/minute.
Clues?
1. I suspect that there was air left in the system after pump replacement as the reservoir has dropped some.
2. No bubbles in the reservoir during hot idle, hot revving.
3. no oil or oil spoo in the coolant
4. no coolant in the oil
5. twice I've found where coolant has burped out of the reservoir cap. not sure why, it's only 1/2 full.
Anyone else seen this?
Mike
Once replaced, engine temp quickly rises to ~195, then slams down to 170. Then up to 195, slams down to 170. All day long.
Now, the h20 pump was leaking, so I just had it replaced. The new pump has slightly changed things... Does this now:
- warm afternoon: engine temp quickly rises to ~195, then slams down to 170. 195, 170, up to 200, stays put.
- chilly morning: engine temp quickly rises to ~195, then slams down to 170. 200, 170, up to 210... and keeps bouncing.
It cycles 2-3 times/minute.
Clues?
1. I suspect that there was air left in the system after pump replacement as the reservoir has dropped some.
2. No bubbles in the reservoir during hot idle, hot revving.
3. no oil or oil spoo in the coolant
4. no coolant in the oil
5. twice I've found where coolant has burped out of the reservoir cap. not sure why, it's only 1/2 full.
Anyone else seen this?
Mike