Alternator & Serpentine belt replacement.

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Drag Line

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Hi all,

70k+ miles & the alternator burned up.

I will replace with a new alternator & I was thinking I should replace the belt as well.

Should I also consider replacing the Idler & Tensioner pulleys as well? I looked to see if there was a write up on this but didn't see one. Do these go bad after a certain mileage or years or are they fairly bulletproof? If they go bad at an approximate time limit, I was thinking about doing it now while I have it apart.
 

JRB

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I've always checked my pulleys by hand after the belt is off. Checking to see how free they spin, are they nice and smooth, any play, etc.

If they feel iffy and the funds are there, couldn't hurt to change them for preventative maintenance.
 

LibertyTC

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Yes generally best to replace belt at 70k, ensure it is an "EPDM" quality. (most now a days are EPDM)
The OEM are plastic pulleys, I'd also just replace pulleys as well. Measure each pulley to ensure you have the correct replacement size diameter.
What year is your Jeep?
 

Drag Line

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Yes generally best to replace belt at 70k, ensure it is an "EPDM" quality. (most now a days are EPDM)
The OEM are plastic pulleys, I'd also just replace pulleys as well. Measure each pulley to ensure you have the correct replacement size diameter.
What year is your Jeep?
2011 KK Renegade. Bought New off the lot to replace an Outback with a slipping CVT transmission.

The idler is steel but the tensioner is plastic. There is no perceptible play in either, side/side or up/down.
Should I replace both anyway or replace the whole idler assembly?

What is EPDM Quality?

I do plan on keeping the old belt 7 idler assembly/pulleys as a spare.
 

Drag Line

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I've always checked my pulleys by hand after the belt is off. Checking to see how free they spin, are they nice and smooth, any play, etc.

If they feel iffy and the funds are there, couldn't hurt to change them for preventative maintenance.

I did check the rotation on each pulley, there is no grinding or binding at any point. They turn smoothly & appear to stay within alignment with no fore/aft wobble. Neither maintain a fast, free spin of more than 2 revolutions after the initial turn. I don’t think the sealed bearings are under lubed or compromised.
I believe they will last quite a bit longer, although I’ve been wrong before. At least they will be easy to change out, at 2 in the morning, on the side of the road, in the rain.

Approximately, where are you in S. FL? I’m NW of Tampa.
 
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LibertyTC

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EPDM stands for..ethylene propylene diene monomer, in other words it's one tough belt and should last 100,00 miles.
The Mopar belts are EPDM, Gates and other companies should all be EPDM today.
It is always a good idea to have spare pulley's just in case something fails.
 

JRB

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I did check the rotation on each pulley, there is no grinding or binding at any point. They turn smoothly & appear to stay within alignment with no fore/aft wobble. Neither maintain a fast, free spin of more than 2 revolutions after the initial turn. I don’t think the sealed bearings are under lubed or compromised.
I believe they will last quite a bit longer, although I’ve been wrong before. At least they will be easy to change out, at 2 in the morning, on the side of the road, in the rain.

Approximately, where are you in S. FL? I’m NW of Tampa.

The pulleys sound like they are in nice shape, and I hear ya on that where they all check out great then the unexpected happens, and yep in the worst time and place haha!

I'm in palm beach county, boynton beach. Drove out to Tampa to get my liberty!
 
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