Inside the Brands: Episode 36 – A Look at EPDM Serpentine Belts

In this episode of CRP Automotive's Inside the Brands we discuss the materials used in the production of serpentine belts, how it’s changed in the last 15 years, and the effects of the change in materials used.

These days, vehicle and belt manufacturers have all but abandoned neoprene for serpentine belts, instead opting for EPDM rubber. Reasons for that change?
- EPDM has a broader temp range than neoprene. Depending on the specific composition, EPDM’s operating range goes from -40* to 300*F and neoprene goes from -40* to 250*F.
- EPDM stands up much better to ozone and oxidizers at high temperatures. Over time, ozone and oxidizers in the air attack rubber and lead to what is known as ozone cracking or dry rotting.
- Service Life. Rather than seeing belts last 40 to 50,000 miles we are seeing many go as long as 100,000 miles before they need to be taken out of service.

EPDM Serpentine Belt Inspection and Service:
Due to the friction and the environment some of the rubber wears off like tread on a tire, which leads to a lack of contact area and friction between the belt and the pulleys. We recommend using a tool like the ContiTech belt wear tester to check the teeth. If the teeth of the belt match up perfectly with the teeth of the tool the belt is fine, but if you can see light between the belt and the teeth, rubber has worn off the belt and it should be replaced.

During a belt inspection it’s very important to check the condition of all the accessories driven by the belt as well as the idlers and tensioners. Since this inspection is now happening closer to 100,000 miles rather than 50,000 miles, it’s a very good idea to remove any components that are showing signs of wear and not expected to last long enough to make it to the next belt change. If you run into a case like this, make sure you check out our accessory drive kits. These kits contain all the belts, idlers, and tensioners for the application and the components are all coming from OEM suppliers so you can feel confident that you are giving your customer the best service possible.

Published on September 9, 2016 Category Tag