97 ctd running 160 degrees. new thermostat. removed and put in hot water it opened between 185 and 190. have never had an engine i couldnt warm up. been playing with this one all summer. any suggestions?

 

Bad temp gage?

 

nope checked water temp as it came out of block with ac thermometer. temp varies between 155 and 165 degrees.

 

Do you have both of the rubber seals? It sounds like water is leaking past the thermostat.
Bruce

 

Sounds normal to me, unless under load these engines run cold, it's the nature of a diesel engine. You have an engine that could pull a freight train, cruising around empty is no work at all for it.

 

I had the exact same problem. Fan clutch doing it's thing without you knowing it! You honestly can't hear it either. Anyway, I had replaced everything too. All I can tell you is that it isn't really something you can hear. But, sounds like the same problem I had. As soon as I put the new fan clutch on, the average temps immediately went up to about 185 or so. That temp is now the "new" average. Funny, now whenever I start the truck I can hear the fan clutch engage, then about 10 seconds later turn off. I guess that's what their suppossed to do--build up pressure within the clutch assembly and then turn off.

Tom

 

I agree with Infidel, the temp seems normal,
that is about what my 97 has always run for temperature.
It does cycle down, then slowly build up, then way back down again.
I still have the original thermostat, so wide swing is normal.
Pulling a 10 pct grade at 7000 feet won't bring it up to 180.
The fan clutch locking engaged is not as common as the opposite, yet it does happen.

 

this is the rad that came off my 90 ctd, same fan clutch. do have both rubbers. 90 ran hot with this set up. changed 90 to 93 cooling components. 90 runs about 185 now. this is the first vehicle i have ever owned that didnt run hot or i couldnt make it warm up. take my 89 yr. young mother to work with it would like to keep her warm. need step ladder to get in 90 or would use it.

 

Did I mention the problem was also on my 97. The engine had 165K miles on it.

How many miles on your fan clutch?


Tom

 

ok guys and gals i have been in this business for 40 plus years and i appreciate all the replys. now i probably need to be educated. under normal conditions the thermostat will not open until the engine reaches a predeterminded temp. now under most conditions engine has to reach this temp before it will open. water temp 160 degrees themo should be closed. it has to be by passing somewhere and i dont understand. it cannot possibly do this without by passing the thermos stat. water flows freely in rad. at 160 degrees. it should not do this if thermostat is closed. i am missing something somewhere. I submit that no matter what the fan does until the thermostat opens the fan or radiator has not control whatever. educate an old man HELP

 

It's bypassing though the heater core. My feeling is that except in the hottest weather or under heavy load you don't even need a radiator, the heater core will do.
When it's below zero I've watched my temp gauge drop down to the bottom of the safe zone from about 160 instantly by just switching the control from recirc to one of the positions that draws outside air though the heater core.

I run a winter front and remove the fan for at least six months out of the year just to keep the heater going.

 

ok if that is true i turn on ac which will shut of water through heater core and temp should rise. ac isnt hooked up yet. will be worth a try. it has to be by passing somewhere. thanks, all suggestions are welcome and appreciated.

 

ok guys it aint by passing through heater. radiator cap off engine cold no water circulation. as engine warms up water starts circulation with thermometer water is 160 degrees. i am going to try another stat. it is not supposed to start opening till 190. water on stove has to be lying to me. will post results when they are in

 

How could it not be passing though the heater core?
There is no valve in the heater line, only an adjustable door (blend door) in the ducting.
Coolant is always flowing though the heater core unless you've done something to stop it.

 

Check Your Fan Clutch!