Can’t figure out why my new pulley is doing this with a new belt

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iboughtatahoe23

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447F73FF-8AAC-41A0-AA55-E12A6357706F.jpeg

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Would happen on my old one here too
 

mikez71

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well i meant when you installed the new pulley, if you happened to see if the water pump pulley had residue on it as well. It could be transferring from that pulley onto your new idler. Water pump pulley is the large pulley below the idler you replaced that also rides on back side of belt.
 
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iboughtatahoe23

iboughtatahoe23

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well i meant when you installed the new pulley, if you happened to see if the water pump pulley had residue on it as well. It could be transferring from that pulley onto you new one. Water pump pulley is the large pulley under the idler you replaced that also rides on back side of belt.
So what am I looking for again if the belts are rubbing against each other or something
 

B-train

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It's just a wearing the paint off.. pulleys used to have a non-painted belt area. Manufacturers have made the process easier for them and just paint the whole thing. Nothing to be worried about.

If it was driving a waterpump, then the paint can cause slippage and noise. Pretty common on 8.1L replacement pumps. I've had to emery cloth off the paint on generators because they would squeal, slip, and cause the belt to get super hot.

You could remove it and sand off the paint if it makes you feel better about it.
 

Doubeleive

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it's going to wear eventually that's just a coating, how fast it wears I don't know. Last one I had on wore out in nothing flat the current one has taken at least a couple years to get like this
pull.jpg
 

mikez71

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looks like rubber residue from old belt to me. either way, i agree, dont worry about it!
 
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OR VietVet

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Not to worry and it looks like the wear pattern matches where the lettering is on the belt. Drive it, should be fine.
 
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iboughtatahoe23

iboughtatahoe23

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It's just a wearing the paint off.. pulleys used to have a non-painted belt area. Manufacturers have made the process easier for them and just paint the whole thing. Nothing to be worried about.

If it was driving a waterpump, then the paint can cause slippage and noise. Pretty common on 8.1L replacement pumps. I've had to emery cloth off the paint on generators because they would squeal, slip, and cause the belt to get super hot.

You could remove it and sand off the paint if it makes you feel better about it.
I don’t think it’s wearing paint off. On my new pulley. It’s like bumps not indentations.
 
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iboughtatahoe23

iboughtatahoe23

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Pretty sure it’s belt material yall not paint wearing off. It’s bumps not indentations.
 

j91z28d1

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that is a bit weird but unless it damaging your belt or the bearings are making noise. I wouldn't worry about it much. just something to watch.

so the paint is fine, it's just building up rubber? and both the water pump pulley and the tensioner pulley are clean and it doesn't build up on them?
 
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iboughtatahoe23

iboughtatahoe23

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that is a bit weird but unless it damaging your belt or the bearings are making noise. I wouldn't worry about it much. just something to watch.

so the paint is fine, it's just building up rubber? and both the water pump pulley and the tensioner pulley are clean and it doesn't build up on them?
Ya it’s just building up with rubber. No noises. And haven’t really looked at the water pump. That thing looks like you have to dump the whole front end to change
 

mikez71

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So you think it’s my water pump pulley?
thats what i was thinking since there was residue on your old idler. doesnt mean your water pump is bad, just keep cleaning the idler pulley and see if it stops or lessens depositing rubber.
 
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j91z28d1

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Ya it’s just building up with rubber. No noises. And haven’t really looked at the water pump. That thing looks like you have to dump the whole front end to change

you wouldn't have to change the water pump over it.. just take the belt off and clean the pulley with some brake clean. same with the tensioner and idler, wipe down the back of the belt and that should at least give you a fresh start.

if it kept doing it.. I honestly don't know. haha
 

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