QuestionQUESTION: My 1995 Dodge Dakota serpentine belt keeps slipping forward on the crank shaft pulley and then shredding. Why is this happening? It literally just started happening today. And we haven't replaced or changed anything having to do with the serpentine belt. We had just recently purchased the vehicle and it came with a new serpentine belt, and had ran fine until today. It happened randomly while we were driving. It was also so violent that it ripped the oil dipstick out, and bent the pipe it sits in. Leaving about 3 inches of the oil dipstick still down in the oil.
ANSWER: Hi Aleena,
Usually when the belts come off it is because the various pulleys that are associated with it are not in the plane of rotation. So take a straight edge and place it between various pairs of pulled to see if there is one pulley that is too foraard or too aft of the others or possibly is tilted from the other pulleys plain of rotation. The most likely pulley is the one that tensions the belt and it may be worn out or loose where it mounts to the engine.
Another possibiilty is that one of the devices being driven is getting a bad bearing which is causing the drive belt to slip on the pulley which then overheats the rubber and breaks down the belt, so try turning each of the pulleys by hand to see if one in very hard to turn.
Please let me know what you find.
Please 'rate' my answer (see below).
Thanks,
Roland
---------- FOLLOW-UP ----------
QUESTION: Ok. Well all of the pulleys spin freely, except the crankshaft, which i don't believe is supposed too. And the tensioner one does wiggle a tad and its plastic, could that have any effect? And we will be trying the straight edge when the weather gets a bit better, and I will get back to you if that isn't our issue.
AnswerHi Aleena,
Treat that pulley similarly to all the other pulleys as regards its plane of rotation. If it either moves forward or back of the plane of rotation of the other pulleys (and if all those pulleys seem to be in the same plane of rotation with one another) then the only pulley that might be either fore or aft of the plane, or twisted/at an angle to the common plane of rotation could be the tensioner pulley. Perhaps the arm upon which it is mounted is twisting because it isn't fastened firmly where it attaches to the engine, or the pulley bearing may be worn and is allowing it to wiggle too much. But if all the devices are appearing to rotate easily then a pulley is suspect.
The other possibility is that A/C compressor is binding up when called upon for action, such as whenever you request windsield defrosting, then the A/C compressor clutch is closed and the compressor is forced to rotate. So even though it is winter that compressor still comes into play. When you rotate the pulley it will feel fine, but when you request A/C or defrost then the clutch connects the pulley to the compressor. If it were binding up the belt would be subjected to alot of fricticn and then breakdown as the result. You could test that theory if the belt is now on by standing nearby at curb idle and have a helper choose the defrost mode and listen and watch to see what it looks and sounds like at the A/C compressor/pulley. Or if the belt isn't on, then start the engine just briefly, long enough to ask for defrost, and then see how easy it is to turn the pulley by hand. There should be some resistance but not feel really locked up.
Please 'rate' my answer (see below). Thanks for rating my first answer, you can do it again for this answer and if you would be so kind as to say 'yes' to the question about a nomination
for 'volunteer of the month' I would be most appreciative.
Thanks,
Roland
