Changed thermostat, now runs cool

[Kain316]

ok thanks. so i just checked and the pin was around 12 o'clock but now i dont remember how the Ts was installed. Does the spring side go towards the engine?

Yes spring side towards the engine

 

[Kain316]

I just purchased mine in December and haven't had money to do my cooling system. My power steering system is new though. Couple days ago my rig blew the top hose barb off completely. Tore down and took tstat out and it was black and brown with no gasket left. My gauge wasn't functional so I took the opportunity to replace the coolant temp sensor and sender. Now I have to get a third radiator...

 

[Zekester]

Ok, so the tstat has the jiggle pin around 12:00 and I massaged the tstat before installing and it moved freely. Installed with the spring facing the engine. Took the rad cap off and hit it with some wd-40 and massaged it. everything seemed to be working as it should.
Let it run for about 20 mins. Never got hot. I was able to touch the engine just about anywhere but the exhaust and it was just warm.
Heater blew the same lukewarm air.
Like i mentioned before, Ive run cars with no thermostat and have never seen one run this cool.

 

[Kain316]

Next time you pull your tstat, look on the flange. There is a temp written on it for when it's supposed to open. The 4.0 is around 197-198 but the 5.0 is 190-195. Sounds like your parts store screwed up or you didn't bleed your system right. I just recently had to do the t stat on mine as the old failed. But it gave me the opportunity to fix the fact that my sender and sensor were both shot. Replaced the grimy corroded old ones pulled tstat to find no gasket left and a black tstat... It had literally burned...I had to pull my single wire connector with pliers since it had siezed on. Now I have to replace a blown radiator... Again

 

[1998Exp]

...
Like i mentioned before, Ive run cars with no thermostat and have never seen one run this cool.

Not very common, but your thermostat may be defective and is stuck open. Probably no choice but to remove and take a look.

 

[Zekester]

Update: it was the thermostat.

I pulled the defective one out and put a Stant in. Seems to be working good now.

Thanks again, everyone