Engine/Transmission (1994 - 1998) engine gets hot

[JoelMartin]

My friend has a 1998 12 valve manual. Whenever he pulls a load up a hill the water temperature climbs to about 200 degrees and wont go down until you let off. He never hears the fan kick in either and this is the third fan clutch. It also has a new thermostat. Any input would be appreciated. Thanks

 

[FourBarR]

Radiator may be plugged. remove and have cleaned.

 

[JoelMartin]

It has a new radiator also. Sorry I didnt know it at the time.

 

[JoelMartin]

Apparently nobody knows whats wrong.

 

[JoelMartin]

Is there a certain brandname anybody would recomend for a new fan clutch and thermostat?

 

[BJMarshall]

Definitely get the thermostat from Cummins or the Dodge dealer. I would say same for fan clutch. 200 is not hot. That is about the area where my fan engages on the 2nd gen.

 

[Skydiver]

Joel, what was the outside temperature and how much weight was your friend towing?
200 is OK.

 

[JoelMartin]

BJMarshall;it has a dodge fan clutch but the thermostat is from Carquest. He is planning to put a thermostat in from Cummins. Skydiver;The outside temperature was around 50 degrees and the gross combination weight around 21,000 lbs. He is going to put a piece of cardboard across the radiator and run the engine at high rpms in neutral to see if he can get the fan to kick in. Is this a good idea?

 

[BJMarshall]

No, unless he cuts a hole in the middle of the cardboard to allow for some airflow. Definitely trash the thermostat and get one from Cummins.

 

[hsmith]

200 is not too hot under heavy hauling conditions. May want to replace the t-stat with one from Cummins.

 

[JoelMartin]

Thanks for all the input,guys.

 

[bdcraig]

Just went through this same ordeal with mine, except it would run in the 220 deg range and sometimes higher even in 50 deg. weather. After a new radiator, 5 fan clutches, and multiple thermostats some with holes drilled the heat was still their. I could never hear or feal the fan kick in. Some said I couldn't hear it because of the straight pipe. On my 2500 I could always hear it and even feel it kick in, so I swapped fans. Now the 3500 stays cool, I can hear and feel the fan kick in. It will barley climb over 190 at 80 deg. outside with a load on a good hill before it starts to cool down. As others have said 200 is not all that hot but mine started the same way about 7 years ago and gradually got worse. Thankfully i figured it out and can now roll on with a load.



Brian

 

[bmoeller]

Since he tows some weight, I'd get a 180* t-stat. Will run cooler.

 

[Vaughn MacKenzie]

If the needle is just going slightly to the right of the 190 mark then that's OK, pretty normal. If temps keep climbing beyond and start going to 210-220 then that's not so good.

If your friend's truck has Cal emissions then he might consider removing the EGR plumbing.

 

[JoelMartin]

The problem is he never hears or feels the fan kick in. He just rebuilt the engine because it got to hot once. I dont think it has CA emissions. BCraig;what difference did it make to swap fans.

 

[JRS]

when you all say "feel the fan kick in" are you talking about the factory engine fan with clutch? How can you check it to see if it's still good?

 

[bdcraig]

The first four fans put on after the factory fan was thought to be bad made no difference. That was what confused everybody. No way that many fans could be bad. But with a known working fan from my 2500 it cools great. Before it would get the temp way up and then 5 minutes later the fan would kick in, well after it needed to. Know it kicks in at 190 deg and starts to cool.



Brian

 

[JoelMartin]

BCraig,are you saying the fan was bad or the fan clutch?

 

[bdcraig]

The fan clutch is what was bad. I just replaced the whole thing. Two were actually damaged in wrecks.



Brian

 

[JRS]

can you test the fan the old way, just by grabbing it and trying to spin it?