Community Forums

snl2106 · 04-27-2012, 02:47 PM

I have a 1990 Monaco Crown Royale. The hydrolic pump belts (p/s) keep going out way to soon. Sometimes in 200 - 2500 miles. Checked the angle of the pump and corrected that but problem still occurs. Ran a straight edge to check alignment and can not find anything else. Anyone with an Idea I havent tried or someone had the same problem with a solution Id appriciate it. The pump does not bind either, forgot to mention that. My other thought is the hydrolic fan. But upon talking to a few other fellow techs they dont have much of a problem with them. So Im stumped
Thanks

ga traveler · 04-27-2012, 05:04 PM

A few years back, one of the engine mfg added a idler pulley to a belt. It seems the distance was too long and caused too much flexing in the belt.

winnbrave1 · 04-28-2012, 08:50 AM

Certain "dumb" questions must be asked. Is it the right belt(s)? Are they routed correctly? Is anything rubbing the belts? Sometimes a worm screw clamp will rub the back side of a belt when too much clamp is sticking through the screw. Is any fluids getting on the belt? Are you using any belt dressing? Are you "rolling" the belts on? Has any accesssory (belt driven) been changed out before the problem started. It may have the wrong pulley size, if so. Are motor mounts good? If one or both are bad, motor could be torgueing and letting the belt hit something. A lot of questions, but belts are usually fairly "forgiving." Maybe this will help to think outside the box.

Gary RVRoamer · 04-28-2012, 09:51 AM

I just found a tiny rock lodged in one of my pulleys (it's a serpentine rather than v-belt) and it was chewing up the belt I recently replaced.

You didn't mention how the belts are failing. Do they just snap, or are they worn or gouged on one edge or another? Flat serpentine or v-type belt?

greystroke · 04-28-2012, 12:01 PM

I will be ordering some belts for my coach next week. Monaco could not help me and sent me emails that they could not. I found my proper belt number at accessfreightliner but they could not give me the AC belt. I have not called Freightliner yet.

My AC belt presently has a NAPA part number so when I put the partnumber into their online database it come up with 4 different belts all slightly different with the same pn. Then I notice my belt had an XL qualifier printed on it. So that is what I will order. The XL is a much stronger belt.

Make sure your belt is the right one. May take some time for an older coach.

snl2106 · 04-30-2012, 08:32 AM

To answer a few things. They are V belts. I did hear about the belt deflection before & think Im gonna make a braket and put an idler pulley on and try that. They belts run true and yes they are the correct belts. In fact Ive used the green HD belts & blew them.
Thanks for all the input guys I really do appriciate it. Anything else to add please feel free

gfs1943 · 04-30-2012, 09:26 AM

Quote:

Originally Posted by snl2106

To answer a few things. They are V belts. I did hear about the belt deflection before & think Im gonna make a braket and put an idler pulley on and try that. They belts run true and yes they are the correct belts. In fact Ive used the green HD belts & blew them.
Thanks for all the input guys I really do appriciate it. Anything else to add please feel free

I worked on some vehicles with GM 6.2 diesels and a $#@%-load of V-belts. Couldn't keep the belts on; they would throw off almost every trip! One of the belts was very long, with a long unsupported run. It's the one that caused the problem. We got an idler pulley for a serpentine belt, fabricated and installed a bracket to let that pulley run against the outside (back) of the long belt, about halfway across the long unsupported run. That cured the problem, so we did the same with all those vehicles.