Shredded Belt 9/27/2010

That's a timing belt around my neck for a v-6 engine.









My car broke down. I pressed the gas and the serpentine belt shredded. The car quit running. Would not crank back up. It cranked over fast, like no compression. It was dead.
It was raining that day and I think it may had something to do with running through water, causing it to jump off. I am also replacing the belt tensioner. When belts jump it is usually oil leaking on it or a belt tensioner going bad unless the belt it just that worn out.

This is on my 1993 Acclaim (Chrysler) with a 3.0 v-6. It is used on a mail route.


So I figured a piece of the serpentine belt that shredded that wrapped around the crankshaft pulley also did on the lower timing sprocket which is right behind it, causing it to jump time. The timing belt was not broke because you can take off the oil cap, crank it over, and see the valve rockers moving, so the cam was moving by the timing belt.

Here you can see where the serpentine belt wrapped around the crankshaft pulley. It needs to come off. It it wound very tight. It came off like spaghetti.









After removing the crankshaft pulley this is the lower timing sprocket. See the notched timing belt around it? This is where a piece of the shredded serpentine belt wrapped around it and caused it to jump a notch. That belt was not even damaged. Good news not to have to take apart half the motor to change out the timing belt. I could see by the marks it had jumped one notch of time. It can be corrected without removing the timing belt since the belt appears undamaged.









The way to take off the belt without taking half the motor apart to get to the tension adjuster is to loosen the center nut on the cam sprocket to where you can just barely slide the belt off and later back on. The way you set a timing belt is by aligning marks on each of the sprockets with the ones on the housing around it. You will have to make sure you get all the marks on all three of the sprockets aligned, both camshafts and the crankshaft on a v-6. Getting the belt slid back on while keeping the marks lined can be a real pain, so persist, it can be done.








I also replaced the serpentine belt of course.
Now it's running fine.

Next day observations: Throughout the next day it done fine. I believe the problem was that belt tensioner. The belt should run in the center of the pulley on it. If it is running towards the edge, it means the spring in it is getting weak. It does not take it being much off-center to cause the belt to jump off, especially when you are accelerating like I was. They make these things cheap, but the price sure is not. Almost 60 for mine.
Stop-and-go driving, increasing and decreasing the engine's RPMs, causes more pressure on the tensioner. So keep it checked. Also keep checked to make sure you do not have oil leaking getting onto the belt. That will cause it to stretch, jump off and maybe shred.