Need help with serpentine belt

doc54

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Hi, I have a ‘97 TJ Sahara with power steering and AC. I recently had my water pump replaced and a few days later my serpentine belt snapped. I bought a Continental Serpentine Belt from AutoZone (Part Number 4060910) and after spending over an hour was unable to get it around all the pulleys/wheels (Too tight to get around). I then purchased a Dayco Belt (Part Number 5060910) and had the same luck. I am correctly routing the belt around everything and am wondering if anyone with the same setup as me (‘97, 4.0, Power Steering, AC) has changed the belt. Could it have something to do with the water pump that was replaced? If anyone has any suggestions I’d love to hear them. Thank you in advance.
 
Yes. Fully backed off the adjuster and still cannot get the belt to fit. I can get it correctly seated around everything but then will be unable to get it around the last one.
 
Can you confirm the belt is routed per this diagram?
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Yeah something must be up, I just replaced the belt on my 97 with zero issues. Can you compare length of old belt with new belt? Also, use the diagram above to confirm routing. Other than that, maybe wrong idler pulley(s) size?
 
Another piece of advice.. Make the passenger side idler the last pulley to go around
 
It's not impossible to get the belt misrouted.
Yes. Fully backed off the adjuster and still cannot get the belt to fit. I can get it correctly seated around everything but then will be unable to get it around the last one.
I happened to think about this last night as I was laying in bed and the thought occurred that you may not have known to also loosen the idler pulley bolt. The idler pulley, highlighted in yellow below, is moved in its adjustment slot by the idler pulley tension adjustment screw. If its bolt that it spins around is not loosened slightly, you can turn the adjustment screw all you want but the pulley won't be able to move in its slot to loosen the belt.

Make sure when you're done to get the belt tight enough that you can barely (!) deflect it 1/2" or so by pushing on it HARD with your thumb at a point halfway along its longest unsupported span.

Capture.JPG
 
I have been trying to route the belt using the diagram that Jerry Bransford posted; which is correct for my Jeep. I have compared the new belt lengths with the old one and they are right around the same size (Maybe a little smaller since they have not had tension on them). I have loosened the idler pulley bolt and tension adjustment screw. One video on Youtube said to leave the belt on the side of the fan/water pump pulley then slide it on after everything else is in place, this did not work. I also tried leaving the passenger side idler pulley for the last one also with no luck. Is it possible that the new water pump that was installed may have changed the position of the Fan/Water Pump pulley making it need a longer belt? Thank you all for the responses.
 
Had this same issue with a parts store continental belt. Correct application, verified numerous times that the routing was correct, but just a smidge too short. Got a mopar belt and it fit, try that.
 
There's no reason for the correct length belt to not fit unless the idler pulley never moved enough in its adjustment slot to give all the slack needed for the replacement belt. The idler pulley has a lot of available travel, enough to give the belt a loose fit until the adjustment screw is tightened. My first TJ was a '97 too with the exact same serpentine belt configuration. I'm thinking the idler pulley bolt was loosened but not enough to allow it to move down freely in its slot to release all the tension on the belt.
 
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For what it's worth, I have a 97 Sahara 4.0 and I used a Continental belt number 4060910 and it fit perfectly.
 
Agree with Jerry--you're missing something and it is most likely the pulley. There is the tension bolt, and the bolt that mounts the pulley. Both must be loose in order to slide the pulley enough to fit a new belt on.
 
For what it's worth, I have a 97 Sahara 4.0 and I used a Continental belt number 4060910 and it fit perfectly.
I had the same # continental belt. Triple checked it's correct for my application. Tried every possible sequence of mounting on the pulleys and it just wouldn't fit. Tried the old mopar belt and it slipped on just fine. Tried the continental several more times, no go. Finally just got a new mopar belt, and pulling the new mopar and continental belts taut side by side over a couple of large pipes the mopar one has just a bit more slack than the continental.
 
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I had the same # continental belt. Triple checked it's correct for my application. Tried every possible sequence of mounting on the pulleys and it just wouldn't fit. Tried the old belt and it slipped on just fine. Tried the continental several more times, no go. Finally just got a mopar belt, and pulling the new mopar and continental belts taut side by side over a couple of large pipes the mopar one has just a bit more slack than the continental.
I don't know... Definitely an odd one. This was the first time I changed my belt, also changed both idler pulleys and compared the oem to what I purchased and all was good. Belt was a hair shorter, which I expected but there's plenty of adjustment on the idler pulley. Everything went fine. Other than preferring a tensioner pulley!
 
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Just tried the Mopar belt with no luck once again. I have the tension bolt and idler pulley bolt both loosened and see no possible way to be able to get the belt to fit. Could it be that the new water pump is larger than original or is in a different position, requiring a longer belt? I’m not 100% positive if thats a possible problem but right now that seems like the only thing that makes any sense to me.
 
The water pump pulley is reused with the new pump. A change in pump pulley location would put the fan into the shroud.

Are all of the idler pulleys original? Maybe somebody replaced one with a larger diameter?

Post some pics of your setup.
 
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jerry correct me if im wrong it's been awhile. but seems like i remember having to turn the adjustment screw opposite of what you would think to loosen the idler pulley. i mean you turned the adjustment bolt clockwise to loosen it and counter cw to tighten. seems i remember tightening mine and bottomed it out and it never got tight enough ! then put a light on it and did some redneck syphering and saw i needed to turn the bolt ccw to move the idler to tighten the belt ? like i said its been awhile......
 
Another thing to consider is that the adjustment bolt can get rusty and bind prior to reaching it's limits when it actually has lots more travel. Spray the bolt with a good penetrant and work it a bit.
 
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