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Topic: Idler pulley Part numbers (Read 588 times) previous topic - next topic

Idler pulley Part numbers

Would anyone have the part numbers for the idler pulleys for a 99 model 8.3?
Are they available aftermarket?  Has anyone had experience with these aftermarket pulleys?
Normally I would go to Cummins, but I figured the idler for Hyd. pump didn't come from Cummins, or least not with the engine.
Thanks.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Idler pulley Part numbers

Reply #1 –
Assuming yours are the same as a 96,it's a Gates 38504,both are the same,got mine on Amazon.If it has any bounce while
running might as well get 2.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Idler pulley Part numbers

Reply #2 –
 John,
Thanks. I have one that's noisey on start up, figured I would change them both since they are the same age.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Idler pulley Part numbers

Reply #3 –
Starting with the ISC's in 99', there are two different idler pulleys. The lower one runs on the outside of the belt (easy belt change), and the upper one runs on the inside of the belt (makes it a bear to change the belt or idler pulley!!!). Unfortunately, I don't have the part numbers handy right now, but if I find them I will post in this thread.
Don
Edit: The the primary (maybe the only) difference between the idler pulleys is that the one that runs on the inside of the belt has a ribbed idler while the one that runs on the outside of the belt is smooth.
Quote from: Green99 –
Would anyone have the part numbers for the idler pulleys for a 99 model 8.3?
Are they available aftermarket?  Has anyone had experience with these aftermarket pulleys?
Normally I would go to Cummins, but I figured the idler for Hyd. pump didn't come from Cummins, or least not with the engine.
Thanks.
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Idler pulley Part numbers

Reply #4 –
Don,
That is correct mine has 2 different pulleys.
Thanks.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Idler pulley Part numbers

Reply #5 –
I would NO deviate from the factory speced idlers (not necessarily brand, but spec).  Others that may look the same may or may not have the correct tension.  Would hate to see you stranded because of too little or too much belt tension causing damage to systems those belts drive.

I have no problem crossing factory OE parts to GATES Corp idlers.  They are very good and the dampening is better than most others:

http://www.youtube.com/watch?v=uTLV5IU_IMM
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Idler pulley Part numbers

Reply #6 –
Here are the Gates part numbers I have the belt tensioners for the Cummins ISC. Verify for yourself before buying!
U270 Belt Tensioners
Gates part #'s
38504 (Pump tensioner ),
38516 (for the alternator)
Don
Edit: Here is a post regarding the belt tensioner differences between the Cummins C8.3 (98' and earlier) and the ISC (99' and later).
Part Number Collection
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Idler pulley Part numbers

Reply #7 –
Looked at mine,the alt. tensioner is in an entirely different spot.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Idler pulley Part numbers

Reply #8 –
Thanks Don, while they look correct I will verify.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Idler pulley Part numbers

Reply #9 –
The alternator belt tensioner arrangement on the C8.3 makes it so much easier to change the alternator belt compared to the ISC. I once had a very painful experience trying to change the alternator belt. A finger got caught between the edge of the pulley and the belt while changing it. Made a bloody mess :o I finally had to resort to loosening the mounting bolt in order to thread the belt on because there just isn't enough swing room for the tensioner to get out of the way. I resolved to buy a half inch longer belt next time to see whether that might make it easier to change the belt while allowing the tensioner to still do its job.
Don
Quote from: John44 –
Looked at mine,the alt. tensioner is in an entirely different spot.
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Idler pulley Part numbers

Reply #10 –
Water pump pliers are your friend. Install the belt with the tensioner "loose" and use the pliers to rotate the detent into its hole.

Been there, done that.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020