If the Serpentine Belt Breaks, What Exactly Happens?

Kayteg1 wrote:

I never bought the story about keeping old belt.
How long you think used, 10 or older belt will last when you reuse it?
I always carry new belt and tools to replace it.
New era belts can last 200,000 miles on cars. Don't know about RVs but once you see the cracks on ribs, you better have new belt handy.

How long do you think that "new" 5yr old belt will last?

It's similar to tires, the rubber gets old even if it's not being used. I wouldn't trust a belt that has been sitting for years.

Keeping the old one will likely give you just as much likelihood of making it into the next town where you can find an actual NEW belt.

My 8.3 ISC is a lot different than the 5.9 truck.
I changed the belts on the Newmar shortly after we to the coach, because of their age, but kept the old one in my emergency pac.

On US 2 in the rest area west of Spokane we pulled in for rest and saw a coach setting with the rear engine compartment open. Being a mechanic with a tool box aboard, I asked if I could help. he showed me his broken belt. we compared it to my spare and it was a fit. Changed it out for him. and told him to pay it forward.

On the ISC in my coach, there isn't much that a belt can hit.
Yes my A/C has its own belt, but runs off a serpentine belt driven pulley.

Brett Wolfe had the right answer like usual; You need to find out what is driven by the serpentine on your coach. If you don't know, ask the mechanic. Our power steering and hydraulic fans are powered by an engine-mounted pump, so loss of the serpentine does not affect the power steering. We have lost the AC compressor belt. We considered a coach with a C-12 engine, and I noticed the serpentine belt powered the AC compressor as well as the alternator. If I had bought the coach, I would have gotten a belt to bypass the AC compressor. In either case, keep spare belt for your coach. If the belts coming off are real bad, I would replace the belts after a year or so to have better spares.

path1 wrote:
I'm venturing into Class A dept and out of Tow vehicles...But maybe might help someone. Not sure if Cummins has same set up if in MH or in pick up?

My Cummins 5.9 in my tow vehicle(2001 Dodge)the a/c compressor froze up and melted my serpentine belt. Wife noticed little poofs of smoke were coming out from hood. Belt was gummy and very warm. Just a matter of time before it broke. When looking for new belt at part store, I had option of "with or without A/C".

LOL Now ask for the 5.9 belt with A/C and a exhaust brake for a 2006.
Took almost a week to get it from Cummins NW. I was in no hurry though, just regular PM stuff for me. Replace before DOTSOR. MH picture is a bit different but just follow the dots. These should last 100k miles easily.

I'm venturing into Class A dept and out of Tow vehicles...But maybe might help someone. Not sure if Cummins has same set up if in MH or in pick up?

My Cummins 5.9 in my tow vehicle(2001 Dodge)the a/c compressor froze up and melted my serpentine belt. Wife noticed little poofs of smoke were coming out from hood. Belt was gummy and very warm. Just a matter of time before it broke. When looking for new belt at part store, I had option of "with or without A/C". I got both belts. I put the "with out a/c" belt on. Being the A/C compressor was still broke and the big town of Royal City WA didn't have any. It allowed me to by pass the a/c pulley and keep all other pulleys going until I could replace a/c compressor on my schedule and not at a garage miles from home. Then after new compressor was installed the "with out a/c" became my spare. So if A/C or belt ever broke again I would be covered both ways, was my way of thinking. I went out to glove box to find notes and of course can't find it. So here is pic from tech manual. Look at diagram at bottom and see "with AC and "without AC" if I recall right I also had to change the belt tensioner in another mounting hole, then change it back. Anyways info is book if your interested, doesn't take PHD.






Again not sure if Cummins in MH is different than in pick up. Sure looks the same to me. Except put in backwards. At our perminate camp cite I've worked on guys DP next to us several times. He spent over $1,000 of overheating problems one year. Kept overheating between AZ and WA. I tested everything (water pump, elec at fan switch etc) And for about 50 cents of dish soap and rinse with water several times solved the problem as dust and road grime plugged up radiator fins and just needed a good cleaning. He still thinks I'm a miracle worker.

When mine broke it took out the wiring to the fan hub. Had a hard time finding a new one. Now I carry a spare.

DICK

OP, on your rig which has a side radiator I believe... the only thing you would see is the red battery light come on. In about a minute your water temp will start to go up as you've lost both the alternator and the water pump. Power steering is part of the side radiator hydraulic system and is not belt driven. The AC is driven by it's own V belt so it may still work too.

One of my friend learned this the hard way. His belt snapped and got a hold of the radiator hose and broke it. The antifreeze coolant drained out and it over heated the car. Honestly, it was his fault. He does not stay on top of his maintenance as it was long over due to replace the belt. Also, when the belt snapped, he did not pull over and stop. He wanted to make it home. His $15,000 car has a busted engine now. Maintenance is a lot cheaper!

Long enough to get me to the next town.

Kayteg1 wrote:

I never bought the story about keeping old belt.
How long you think used, 10 or older belt will last when you reuse it?

The answer is totally depends on the engine and what the chassis maker drives off the serpentine belt.

Our first two DP's had a separate belt driving only the water pump. Serpentine belt ran the alternator and A/C compressor.

Our current coach's serpentine belt drives water pump and alternator, with a separate belt for A/C compressor.

Please check YOUR owners manual for the information on YOUR coach.