Engine/Transmission (1998.5 - 2002) Serpentine belt, water pump, belt tensioner, thermostat....

[Gordon Maney]

I had a different thread regarding the fact that my truck threw a belt off. It was a quite new belt, and so I am uncertain as to why it would have done that. No surprise, it overheated quickly, though not badly.

In the interests of being thorough, I think I will replace the water pump [since I am at 125,000 miles], the belt tensioner [although I replaced the bearing at the same time as the belt, about 6,000 miles ago], and the thermostat.

Anything I am not thinking of here? I read in some threads I found where the tensioner in some cases had contributed to the belt coming off. So, as it is not so good to have a belt come off at road speed while out of town, or anywhere for that matter, I think I will replace it.

Any handy tips from those who have done this job on this engine before? It is a 2001. 5, HO, 6 spd. , 2500 4X4.

Thank you... .

 

[Gordon Maney]

... . also, would you get all of this stuff from the Cummins dealer, or would you go somewhere else?

 

[PC12Driver]

I bought my water pump and t-stat from my local Cummins dealer (as well as the Fleetguard EG pre-mixed coolant). I bought the tensioner from Geno's.



Swapping out the parts is a simple job. Two bolts on the water pump and three on the thermostat (I think). The t-stat and water pump bolts are torqued to 212 in/lbs (and that's INCH/pounds, as per the service manual). And when you add the coolant again, do it with the engine off. The thermostat has a "jiggle pin" that will allow the system to vent air from the system. If the engine is running, the pin closes and doesn't let the air escape (again, per the manual).



Abouth the only thing I would suggest in addition is to pull the radiator out and clean it while it's empty. These things collect an unbelievable amount of crud between the radiator and the intercooler, and the only way to clean them out completely is with it out of the truck. That'll also give you a bunch of room to work on the tensioner and water pump. Maybe swap the upper and lower hoses in the process (got mine from Geno's, along with the handy clamp tool for the hoses).



And I'd swap the belt, too. Just 'cause you never know...

 

[Gordon Maney]

I did end up getting the pump, thermostat, and tensioner from Cummins. I had not long ago gotten an idler pulley from Geno's. Interestingly, it has barely perceptible play in it, so I am going with the new one, an assembly, not cheap, either.

The radiator idea is good. Given some other things I have to do, I may not do it just now, but will soon.

I had no trouble with radiator drain valve, but have read of replacing its O-ring. I wonder if that valve simply pulls out, or is there some trick? Is the O-ring most easily sourced from the dealer, or elsewhere?