Snake in the Engine (Serpentine Belt)

There's a belt that snakes through your engine.  It's even named for a snake, the serpentine belt.  It'll bite you when it breaks, possibly leaving you stranded.  So, it's good to know a little about this snake-like belt.

In early engines, there were lots of belts. They were used to convert the rotating power of the engine to turn a mechanical part.  But engineers had an idea.  Why not consolidate all those belts into one that ran a bunch of different parts simultaneously? Voila!  The serpentine belt.

It's found in the front or side of your engine unlike older belts which were often in a V shape, the serpentine belt has ribs on it which more effectively connect with the pulleys that power the other components.  A serpentine belt may power the water pump, power steering pump, alternator, and the air conditioning: all from one crankshaft. 

Now, all that's fine when everything is working well and the belt is intact.  But when a serpentine belt wears, gets loose, or breaks, it can affect many engine components at once.  Not an ideal situation. 

If you hear squeals coming from the engine compartment, see a battery light, or the engine overheats, those could be signs that your serpentine belt needs replacing.

The good news is that they usually last a long time, from 60,000-100,000 miles or 100,000-160,000 km.  Still, they don't last forever, and your vehicle's manufacturer usually recommends replacing them when they've gone close to the expected maximum.  It’s also recommended that you replace the pulleys and belt tensioner at the same time as they have the same service life. Regular maintenance and inspection of the serpentine belt is not only a good idea; it’s one of those things that you should not let "slip" by.

Tuffy Tire & Auto Service Batavia
301 S. Randall Rd
Batavia, Illinois 60510
630-879-9941