leeboy

Its about 10 celsius here...(50 farenheit) Ive noticed sometimes after letting the truck warm up for a few minutes, and taking off driving normal down the highway to work, my temp gauge is climbing past the mid way point before it kicks in and starts to go down. Now last summer, i was towing my car ( 30 celsius, 86 farenheit) and i was climbing a hill to the track, and afer about 10 minutes of climbing the temp gauge was burried to the "MAX" ...i jumped out and looked, but no over flow or gurlgling of water. So , i let it idle and it didnt want to come down til it was shut off for about 20 minutes.....and then it was still warm. ANy ideas, do clutch fans malfunction or the gauge? Any tips on keeping it from overheating( if it was oveheating?) this summer?

HOHN

Here are my thoughts:

1) First validate that you actually have a problem. A basic water temp gauge is easy to come by and will validate the dash gauge. Jeg's has cheapos for less than $30.

2) Make sure that your crankcase vent hasn't gunked up the radiator. This is pretty common in that the crankcase's oily gases end up leaving a greasy film on the backside of the radiator that eventually gets gunked with dirt and will completely block airflow at times. This is a VERY common condition easily remedied by cleaning the radiator with a good degreaser like Simple Green, Purple stuff, etc.

3) Finally, you may want to change the T-stat to the Cummins 180º unit that replaces the factory 190º unit.

Clutch fans do malfunction, but they tend to lock up when the fail, not freespin. That would be very noisy and easily detected. It's POSSIBLE that your clutch is bad.

Will your clutch lockup in hot weather? When the fan on these things locks up, there's no mistaking it. It's so loud that you can clearly hear it over the roaring clatter of the Cummins.