Engine/Transmission (1994 - 1998) Thermostat question!

[Jim Fulmer]

Those of you that have had thermostat problems what exactly did it do. I was sitting in traffic the other Morning for 15 Min waiting to get on Base and when it was time to drive through the gate I looked up and transmission was at 190... OK fine I was in gear idling but the engine was at 210 or so..... this was a first in 28K. As soon as I started moving it cooled down to 190 range and stayed there but I didn't hear the fan engaged..... hum. I have never seen this truck get over 200 unless the fan was taken off and it won't do it again and the fan clutch work's and did a bunch of times on my 5800 mile trip with no problems. I was thinking about changing the stat for the heck of it.



Jim

 

[Dieselnerd]

It's been my experience that a bad thermostat runs too cool. The rubber ring around the thermostat gets partially sucked into the passage and water flows all the time. Other times when they fail, they seem to stick in the open position.

 

[WDaniels]

I've been getting hay for the hay bags before and the engine would top 200 and higher due to extended idle times when it's warm out. 80+degrees. Doesn't sound like anything is to amiss there. If it was hot out and you sat for 5 minutes on pavement that is hot it won't take long for the engine to heat up. I have seen thermostats stick closed before. You or anyone else use any kind of stop leak for the radiator? Just keep an eye on it and determine how long you idle, how hard you were running it before you stopped, were you towing anything, temps etc... before you go and change a bunch of things.

Hope this helps.

WD

 

[Jim Fulmer]

WDaniels, I wasn't running it hard before the idle session just normal empty crusing, I'll keep and eye on it and see what happens.



Subject change: How is the cam doing, I was up at Piers's a few weeks back and they were shipping one out to Alaska!