Community Forums

TurboDaveTX · 11-29-2021, 02:39 PM

We all know that the later model DEF System heads are a problem that will cause sidelines! We all try to watch out and get in front of issues like that.

To that end, I am having my '15 CS serviced and doing some preventative maintenance. I decided that it was also a good time to replace the engine fan belts, since any one of the three belts will sideline you. So I took pictures of the numbers on the existing engine belts, and ordered replacements.

Service people were working on it today and called and said the belt for the Alternator (which is one that had not been listed on belt replacement list) as a Cummins 5VX680. If your alternator belt breaks, you are probably going to be down on the side of the road shortly! Service people called and said the alternator belt I gave them was not the same as the belt that is on the coach. It is the same number, but it is NOT the same belt! Upon discussions with Cummins, it seems that this is something they are aware of, but they don't stock the double V 5VX680 they install on the alternator from the factory. In fact these double V 5VX680 is custom made to order and may take three weeks or longer to obtain a replacement! I didn't ask what this "customized 5VX680" belt will cost, but it will likely be the most expense engine belt I have ever bought!

This is a heads up! Don't know if the later model ISX 15's have this same belt arrangement or not, and I don't recall seeing a post on IRV2 that said the alternator belt on the coach is not the same one that crosses even to Cummins! Photo of belts is on Belt etc.

Turbojack · 11-29-2021, 03:38 PM

I have been wrong before but I believe the alternator comes from Spartan. So that may be why the belt difference.

When Foretravel was making their own chassis they were suppling the alternator.

777 Driver · 11-29-2021, 05:59 PM

Quote:

Originally Posted by TurboDaveTX

...To that end, I am having my '15 CS serviced and doing some preventative maintenance. I decided that it was also a good time to replace the engine fan belts, since any one of the three belts will sideline you. So I took pictures of the numbers on the existing engine belts, and ordered replacements.

Service people were working on it today and called and said the belt for the Alternator (which is one that had not been listed on belt replacement list) as a Cummins 5VX680. If your alternator belt breaks, you are probably going to be down on the side of the road shortly! Service people called and said the alternator belt I gave them was not the same as the belt that is on the coach. It is the same number, but it is NOT the same belt! Upon discussions with Cummins, it seems that this is something they are aware of, but they don't stock the double V 5VX680 they install on the alternator from the factory. In fact these double V 5VX680 is custom made to order and may take three weeks or longer to obtain a replacement! I didn't ask what this "customized 5VX680" belt will cost, but it will likely be the most expense engine belt I have ever bought!

This is a heads up! Don't know if the later model ISX 15's have this same belt arrangement or not, and I don't recall seeing a post on IRV2 that said the alternator belt on the coach is not the same one that crosses even to Cummins! Photo of belts is on Belt etc.

It's always good to have spare belts on board.

A failed alternator belt will disable the alternator as a source to keep the chassis batteries charged which will result in battery discharge...unless...another source of charging is connected to the chassis patteries. Don't forget that the generator will charge the chassis batteries thru the Battery Isolation Manager or thru the Auxillary (Battery Boost) Start System. I've also read that some have temporarily used a simple battery charger plugged into an inverted circuit and connected to the chassis batteries.

Those strategies would, I believe, work for a failed alternator to limp your way to a location where it would be more convenient to replace the alternator (or belt).

Take care,
Stu

Gary.Jones · 11-29-2021, 06:34 PM

Dave

I just dont think that any of these coaches have a belt on them that is made top order.... I just dont believe that. I also dont believe that there are any belts that are a double v belt. I have owned a 15 Anthem and a 19 Cornerstone and what I have seen are belts that are quite wide and flat and thick single "V" belts activating the 12 Alternator. Our alternators put out a lot of 12 volt amperage so they often have big thick belts, but anything I have ever needed on either coach were ready made, easy to get my hands on belts. Something is wrong with the information you are getting, or I dont understand what you are saying.

I carried a spare belt for every belt that I had on the Anthem and I have a spare belt (they are different) for every belt that I have on my Cornerstone. Every one of those belts was available from NAPA or on like at Amazon, or some other online truck supply company.

Call Entegra and Spartan and see what you hear. Maybe someone else with your same year and model of coach will come on here and be able to read their belt part number and get you going.

If I'm wrong, please come back and let us all know.

Gary