I just replaced my thermostat this weekend. I didn't think it was bad, but replaced it anyway. To my surprise, it's running a little bit warmer. Now the needle gets up to the O in Normal, but the odd thing is that when idling at a light, the needle jumps pretty quickly between the N and R and back every 20 seconds or so. Do you think the new thermostat is just cycling? I also just replaced the radiator. I have an early 95, water pump inlet is cast as part of the pump, this was a new Standt 205 thermostat.

 

might still have air in the system.

 

x2 on air, I cant imagine it JUMPINg if it was anything other than air or loose wire on sending unit.

 

Sounds like a loose wire on the sending unit

 

Where is the sending unit for the water temp, by the way?

 

 

Thanks, I'll check the sender connection. Entirely possible that it got bumped in the course of thermostat swap. I think the air should be out of it after 50 miles or so, but that could be too.

 

We have a water temp light?

 

Yeah I didn't know that Either lol

 

I wonder what temp that it goes off at? I've had mine up to 230 before and now light..

 

Not sure what it goes off at but it in the panel with the WTS and WIF lights. It just says "engine Temp". Bill, Rick and I were discussing this a while ago and I think we decided some trucks didn't have the light. Or was it the E's didn't have the light. I can't remember. Mine has a light and a gauge and an aftermarket gauge!

 

hight temp water light goes off at 241deg

 

And when it goes off you take notice. If I recall it says:
ENGINE HOT
I had mine go off when I blew a heater hose on route 66. It's very impressive.

Rog