Serpentine Belt Shifting

[MEGARAM]

Interesting problem just cropped up on MEGARAM. Last weekend noticed the serpentine belt had shifted back toward engine one notch on the pulleys, cutting away one grove width of belt. Since I had 90,000+ miles on MEGA, I went to Advance and purchased a new belt and installed it. When I started the engine, the new belt shifted one groove back toward the engine with the edge running over the side of the air conditioning compressor pulley. Stopped engine, reset the belt in alignment on all pulleys and restarted with AC off. Belt tracked fine until I kicked air on. Then the belt tracked off one groove again. As the week has progressed, the new belt has shifted a total of two grooves and cut the new belt. Have an appointment with the local Dodge dealer tomorrow. Has anyone else had this problem or is there a TSB out on the problem? TSB link/page on this site is under construction. Any help appreciated as I hate to leave the dealer to his own imagination without some pre-help! By the way MEGARAM is a 1999 QC 3500 dually 2WD ISB 24V with enhancements!

 

[Alan Reagan]

Yeah, but it's an old TSB.



http://dodgeram.org/tech/tsb/1998/09_04_98.htm



You may want to check your belt tensioner pulley to see if it is loose or moving. I'll look around. I've seen something else about belt allignment and what to check. Is it making any noise (you know what I mean). I think the main cause for this shift is going to be the tensioner pulley because of its location next to the AC. When the AC is turned on it causes the extra stress on the pulley. It is probably shifting towards the engine, right?

 

[MEGARAM]

The TSB is for a 8. 0 L V10. I don't think it would apply to the Cummins but I will check for pulley alignment etc. Are there any TSBs particular to this problem on our Cummins?

 

[trning]

Hi

Your belt tensioner will be the problem. I work on a large truck fleet and I've seen this often with belt tensioners that are worn or weak. If the tensioner is weak when you put it under a load the can't keep enough tension on the belt and it moves over a groove.

 

[Alan Reagan]

That's what it sounds like. Get one of the Practical Solutions replacements. That's your best bet. (406) 727-5144. Ask for Gordon.

 

[TowPro]

Does the PS replacment come with the spring, or just the rebuildable pully?

Originally posted by Alan Reagan

That's what it sounds like. Get one of the Practical Solutions replacements. That's your best bet. (406) 727-5144. Ask for Gordon.

 

[Alan Reagan]

Just the pulley. But it's a bearing replaceable unit where the old one is throw away. That is a good point to think about. According to the service manual, incorrect tension will cause this problem, also. Usually it's the pulley bearings have a little play and allow it to move under load.



Edit: Here's the website. Just scroll on this page.



http://www.psdieselproducts.bizland.com/index.html

 

[MEGARAM]

Just so happens I ordered the pulley at the same time I ordered my boost module over a year ago. I installed the module but not the pulley. I'll install the pulley tonight along with another new belt. I'll let you know if this fixes the problem. Otherwise, its off to the dealer tomorrow!

 

[MEGARAM]

Installed new Practical Solutions heavy duty idler pulley and new belt last night. Everything tracking Ok for now. I priced the complete idler/tensioner assembly at Dodge dealer yesterday, $160. They're really proud of that part!

 

[Alan Reagan]

Megaram, That should take care of it for good. All it takes is a little movement in that pulley and the belt will start to track off.