Serpentine Fan Belt tearing edge off

[Blakers]

The serpentine fan belt on my 03 Ram just lost it's back edge today. I was sitting at the post office and heard some slapping noises going on, then it stopped. I looked and there is a strip of fan belt laying on the ground under the front of the truck. The rest of the belt is ok.

After getting home I find the belt is riding with proper alignment on the crankshaft pulley, the power steering pulley, and the top idler pulley. It is one groove back from where it should be on the alternator and air conditioner pulleys. Since the belt travels in a clockwise rotation, the point at which it moves back a grove is at the tensioning pulley (which is smooth). Alignment looks good on everything, the bearings in the idler and tensioner appear fine with no wobble. And everything moves nice and true when the truck is idling.

Could this be an issue with the belt itself? The grooves in this belt appeared to be shallower than some I have seen. It's a Gatorback belt made in Mexico I purchased from the local parts store I deal with all the time.

Thanks.

 

[Wayne M.]

Blakers, one edge frayed or damaged like that usually means there's a misalignment somewhere. A pulley is in or out from the rest. Even if everything is square, if one pulley is further out, it will cause havoc. Has any related work been recently done?

 

[seafish]

Possibly out of alignment, but more likely worn bearings on a pulley allowing wobble or a worn tensioner that is allowing too much play.
Need to remove the serp belt and then check EACH and EVERY pulley for excessive play or excessive noise or excessive tightness, which would indicate bad bearings at that pulley. It might even be more then one bearing. The PS pump is in fact allowed to have some in/out play, but no side to side. If those all check out, then likely the tensioner is worn and allowing the belt to wander due to lack of proper tension.

 

[Blakers]

Thanks guys! No recent work has been done. All the components are original except water pump, which I changed 3 or 4 years ago and shouldn't have any bearing on it anyways. I did change the power steering pump, and yes the pulley does move some in and out. Tightener idler bearings seem good with no play, and top idler bearing seems good with no play. Is there a way to check the tensioner with a torque wrench? It has quite a bit of tension, though I don't know what the specs are. It's a pretty good pull with a 20" breaker bar to release the tension.

 

[Wayne M.]

Here is a discussion dealing with the belt. #35 has my suggestion for holding off the tensioner so all the pullies can be examined. Don't overlook the waterpump even though you changed it. Some of them have reports of a short life.

 

[Blakers]

The water pump is from Autozone and leaks (third one so far), but the shaft and bearings are good.

I could take it back to Autozone for a replacement, but I am going to order a new one from Geno's that hopefully will not leak. For now I just put up with the occasional drip.

Here is a discussion dealing with the belt. #35 has my suggestion for holding off the tensioner so all the pullies can be examined. Don't overlook the waterpump even though you changed it. Some of them have reports of a short life.

 

[Wayne M.]

This is my water pump experience. So far so good as of today.

 

[Blakers]

I think these are the easiest water pumps to change on any vehicle. Other than draining the coolant, there is almost nothing to it. Loosen the belt tension, pull the belt to the side out of the way, remove two bolts, pull out pump, make sure surface is clean and o-ring is in place, replace pump, install bolts, re-install belt, add coolant and you're ready to run.

One thing I learned - after draining coolant, the easiest way to add coolant is through the vertical heater hose connection on the back of the engine. That way you don't have to worry about it air locking through thermostat and not getting enough in. Been there done that. Couldn't get it hot enough for the thermostat to open and let enough coolant circulate.

This is my water pump experience. So far so good as of today.

 

[Blakers]

I think I found my problem - tensioner pulley is worn some causing it to align belt in such a way that it directs it toward the back on the a/c pulley. Can these tensioner pulleys be easily replaced? Back edge on a/c pulley is not very high either, so it does not hold belt from riding up on it.

 

[seafish]

I think I found my problem - tensioner pulley is worn some causing it to align belt in such a way that it directs it toward the back on the a/c pulley. Can these tensioner pulleys be easily replaced? Back edge on a/c pulley is not very high either, so it does not hold belt from riding up on it.

How many miles on the tensioner?? If high miles, then the spring also wears out over extended time, and low spring tension can lead to unevenly worn pulley like you have. So that being said, perhaps it is just best to buy the entire new assembly instead of replacing only the pulley.

 

[Blakers]

209,000 miles, but there's lots of tension. And it moves smoothly. Takes a lot of effort to pull it down with a 20" breaker bar. Where is a good place to buy a tensioner or tensioner pulley?

edit: I see the tensioners for around $80 at Rock Auto and the pulleys for around $14.

 

[Dick Langendorff]

Cummins built your engine. Go to Cummins for your parts.

 

[Blakers]

Signs of belt tension failure http://www.rockauto.com/info/64/BeltTensFail.html

Gates http://www.rockauto.com/catalog/moreinfo.php?pk=960207&cc=1413470&jnid=452&jpid=0

 

[BigPapa]

For what it's worth, I'm still running my original '95 tensioner. Right at 20 years old and 500K miles.

Watch. It'll go out tomorrow.........

 

[Blakers]

Cummins doesn't make belt tensioners. The original was a Dayco.

Cummins built your engine. Go to Cummins for your parts.

 

[Blakers]

Well I purchased a Gates belt tensioner today and installed it. After the installation I would not recommend the Gates. First, on their site it says it is made domestically, but the box said it was Chinese. It seems to be constructed well, but after installing and relieving the tension with a 1/2" breaker bar, and having to pull it all the way to the end of its stroke, part of the aluminum webbing in the arm actually started breaking. I was able to get the belts on and they ran true and straight, so hopefully it will solve my problem.

After removal, I found that the original tensioner was a Dayco, so I would suggest replacing yours with a Dayco as well. Not sure where they are made, but seem to be built stronger than the Gates.

 

[rashwor]

Every time my belt on my 5.9s ('92, '99, and '05) has done this, it has been the belt tensioner assembly.

Yeah, I would pass on the gates tensioner and water pumps. They used to be good, but my recent experience with each say not any more.