Supercharger drive belt idler pulley. Replace $540. Rebuild $27.
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Supercharger drive belt idler pulley. Replace $540. Rebuild $27.
EDIT: replaced original file with modified file using the Dayco 89130 plastic pulley.
Part number 113-20204-19. Supercharger Drive Belt Idler Pulley. Replacement cost from MB is in the area of $540. I just rebuilt mine for $27.
I pulled the belts off my car, spun the pulleys, and found three with dry bearings; serpentine pulley on the double supercharger drive belt idler pulley, serpentine idler pulley, and the serpentine tensioner pulley. I decided to replace them all but the cost of the above pulley was outrageous. I spent a few days researching and here is my solution.
See attached document for the part numbers and DIY info.
Hope this helps others.
Mod, if it is worth a sticky somewhere, I'd be glad to accept it!
Cross-posted at the other forum.
Part number 113-20204-19. Supercharger Drive Belt Idler Pulley. Replacement cost from MB is in the area of $540. I just rebuilt mine for $27.
I pulled the belts off my car, spun the pulleys, and found three with dry bearings; serpentine pulley on the double supercharger drive belt idler pulley, serpentine idler pulley, and the serpentine tensioner pulley. I decided to replace them all but the cost of the above pulley was outrageous. I spent a few days researching and here is my solution.
See attached document for the part numbers and DIY info.
Hope this helps others.
Mod, if it is worth a sticky somewhere, I'd be glad to accept it!
Cross-posted at the other forum.
Last edited by bbirdwell; 05-09-2022 at 12:20 PM.
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Just remove the belts and spin each pulley. A good pulley is totally silent. A bad pulley sounds like an old roller skate wheel and you can even feel the vibration. Once you hear the dry bearing sound you'll never mistake it for anything else. Silence = good. Noise = bad.
I could have just replaced the bad pulleys but I figured with 90K miles I'd just do them all at one time and be done with it until I put 180K miles on the car....
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#10
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I was just on rockauto looking for the Dayco 89130 & they reference an outside diam. of 90mm but Dayco website says 89mm. Rockauto wrong or does anyone know if there has been a real change to the pulley size?
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Don't fixate on the 1mm. Depends on if the caliper was on the outside rim, the inside ridges, or if the caliper was held at an angle.
The two pulleys are separate so even if one has a difference in circumference, they do not interfere with each other. You're looking at a difference of 3.1mm in circumference (~1/8") between the two listed numbers.
The two pulleys are separate so even if one has a difference in circumference, they do not interfere with each other. You're looking at a difference of 3.1mm in circumference (~1/8") between the two listed numbers.
#13
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Just replaced mine.....its at the back of the motor under the throttle body Y joint.....you will need a long 1/4" drive to remove and replace. Simple job really but removing and replacing the bolt without dropping it is the hardest part.....a magnetic socket helps.....cheap insurance.
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Just replaced mine.....its at the back of the motor under the throttle body Y joint.....you will need a long 1/4" drive to remove and replace. Simple job really but removing and replacing the bolt without dropping it is the hardest part.....a magnetic socket helps.....cheap insurance.
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So 2 years on, just wondering how the bearing has been going in the plastic DAYCO pulley? I saw one amazon review complaining about the bearing. Would it be worth pressing out and throwing away the bearing it comes with and putting in the NSK 6203 ZZC3 straight away?
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I replace all pulleys and tensioners every 60,000 miles (~ 97,000 km) and did so on my last major maintenance. The Dayco was still good after the 60k miles and 40 months of use (but I replaced it anyway).
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On a side note, the supercharger tensioner is very expensive, my bearing is fine, tension seems ok just the pulley itself is rusting out.
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For grins and giggles I ran the numbers:
Stock pulley diameter equal to 152.4mm.
Circumference is equal to 2 pi * radius equal to 6.28*76.2 = 478.5mm.
Supercharger pulley diameter 90mm.
6.28*45 = 282.6mm
478.5/282.6 = 1.69
6000 rpm redline pulley turning at 10,159 rpm. Lower speed bearing should work fine; I just practice overkill
Last edited by bbirdwell; 01-02-2019 at 08:51 PM.
#24
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So I’m having a hell of a time with this. I’ve had to sand basically the entire flange off to have any spacing between the two pulleys. I’m positive the bearing is seated, the circlip is secured in the groove. What the hell?
#25
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checking! Stupid me.