Serp Belt problem (yes I searched)

i got home from a nice vacation in California to find that my serp belt on my truck is ridiculously loose! It's so loose that the tensioner wouldn't even help! when i left two weeks ago the truck ran great! all the pulleys are still there and nothing is loose, so I was just wondering what could have caused it, more for the general knowledge of what happened. thanks guys

The only good way to diagnose the issue is to get a new belt, remove the old belt and compare their lengths. If the belt is stretched, I would say the belt is defective, since they should not stretch. It is always good to have a spare belt under the back seat anyway.

A common issue is the alternator. There is adjustment there as well. Maybe the alternator walked on the bracket and needs to be reset and tightened. Remember the bolt in the back of the alternator. If left out, the alternator will bend forward and cause a loose belt. There is a similar bolt on the back of the power steering pump.

4x4life05 said:

i got home from a nice vacation in California to find that my serp belt on my truck is ridiculously loose! It's so loose that the tensioner wouldn't even help! when i left two weeks ago the truck ran great! all the pulleys are still there and nothing is loose, so I was just wondering what could have caused it, more for the general knowledge of what happened. thanks guys

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Did the stupid metal piece that we call a tensioner snap in half while you were gone? The thing that the long bolt runs through.

BigBlackHeep said:

Did the stupid metal piece that we call a tensioner snap in half while you were gone? The thing that the long bolt runs through.

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I don't know yet, I haven't checked that because I was already late for work. I'll check as soon as I get back home. I didn't know that the alternator could be adjusted? Thanks I'll check for that too!

4x4life05 said:

I don't know yet, I haven't checked that because I was already late for work. I'll check as soon as I get back home. I didn't know that the alternator could be adjusted? Thanks I'll check for that too!

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Sometimes there can just be a hairline crack starting in it and you won't realize it. Check carefully.

I see from your profile that you have a 94. Make sure that you have loosened all the pertinent bolts holding the power steering, enough so that the so-called tensioner (aka "sad excuse for a tensioner") can move freely, and make sure that it really is moving the pump when you turn the jack screw. If you're really at the end of the travel of the screw, then you need to find out what's broken.

okay found it! The belt had started to tear at one point and it caused everything to stretch out. I took your advice and bought two, keep one under the back seat now. Thanks!!!

Yes, it is certainly a procedure to change a belt on the XJ. Remove air box, loosen nuts behind power steering pump, loosen nuts in front of and below the pump, and loosen the top bolt (maybe even remove)

Now it is strange, we have one device with a spring to tension a belt now adays