Author Topic: Idler Pulley Bearing  (Read 1541 times)

Harry

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Idler Pulley Bearing
« on: May 22, 2022, 10:58:14 »
I posted a question before about the bearing for the AC idler pulley and need to ask again.  The outer race of the bearing I removed is just under 40mm (39.89 mm), measuring with a set of calipers.  It is just over 12mm thick (12.1mm).
I ordered a 40mm x 12mm and it “felt” too big.  I had to press it in and once installed, it didn’t roll smoothly - so I pulled it and want replace it again.  Does anyone know the exact bearing it requires?
Thanks!
Harry
Harry Bailey
Knoxville, TN
1966 230SL
Automatic

dirkbalter

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Re: Idler Pulley Bearing
« Reply #1 on: May 22, 2022, 16:44:46 »
Harry,
I measured the bearing from my 108 idler.
Assuming you have an original AC, it should be the same and is 40mm.
Does your old bearing have a number stamped on the race?
Dirk
66 230 SL
70 280 SEL
53 CHEVY 3100
18 C300 COUPE
05 HD FLSTNI

Harry

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Re: Idler Pulley Bearing
« Reply #2 on: May 22, 2022, 23:24:00 »
Hi Dirk,

I can very faintly, maybe see something on the OD.  I’ll try to see if I can clean it some way without obliterating what’s there.  My measurement is essentially the same as yours.

Thanks again,
Harry
Harry Bailey
Knoxville, TN
1966 230SL
Automatic

dirkbalter

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Re: Idler Pulley Bearing
« Reply #3 on: May 23, 2022, 00:09:31 »
Bearings are not all the same with respect to quality. I have had no name bearings, coming from who knows where, with issues. They had feel-able play and resistance when turning. I wouldn’t buy standard parts like this from MB but I like to buy name brands, SKF , FAG, …
Good luck
Dirk
66 230 SL
70 280 SEL
53 CHEVY 3100
18 C300 COUPE
05 HD FLSTNI

Harry

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Re: Idler Pulley Bearing
« Reply #4 on: May 23, 2022, 10:50:19 »
Thanks again Dirk.  I really appreciate you helping me with what should be a simple matter.  I'm going to order another bearing this morning and see if perhaps I did indeed just get a faulty bearing.

Harry
Harry Bailey
Knoxville, TN
1966 230SL
Automatic