Replaced smog pump bearing (pictures inside) - PeachParts Mercedes-Benz Forum

amg280 · #1 02-01-2009, 07:01 PM

Hello all. Do to the great advice and resources of this forum, I successfully replaced the bearing in my air pump today. Total cost: about $25. Total savings: about $600 if I bought from dealer

The car was my 95 E320. Total time, about an hour and a half, start to finish. I took the airbox out, radiator shroud, and plastic mechanical fan. That gives you alot of clearance to get to all the bolts.

I bought the bearing from bearingsdirect.com, part number: 32BG05S18G-2DS

Below are some pics. Very simple install. Would recommend a small press to get the old bearing out.

pawoSD · #2 02-02-2009, 12:29 AM

Was the old bearing grinding? What are the warning signs........so far it seems to operate smoothly/quietly on our 300E.....I am looking for a pre-90 junkyard car so I can get the setup that has no pump and swap it on. Then no worries!

amg280 · #3 02-02-2009, 07:56 AM

Quote:

Originally Posted by pawoSD

Was the old bearing grinding? What are the warning signs........so far it seems to operate smoothly/quietly on our 300E.....I am looking for a pre-90 junkyard car so I can get the setup that has no pump and swap it on. Then no worries!

Yes, the old bearing at first started to whistle at certain RPM's when it was cold out. About a week ago, it started grinding really bad. I knew it wouldnt last much longer so I replaced it.

KarTek · #4 02-02-2009, 08:08 AM

Nice job! Were you able to search that bearing site based on the MB part number? It still floors me when I see MB PN's and logos on every little part in the car! Most times it's good though...

amg280 · #5 02-02-2009, 08:15 AM

Interestingly enough, I searched the bearing part number on this site. Upon removing the old bearing, there was a MB part number on it (see pic 3). For fun, I entered that part number into a search and it does not come up with anything.

Gilles Kay · #6 02-02-2009, 12:40 PM

Great Job!!! Did this same job on my '92 300E 2 years ago at 131,000 miles using the same bearing. Still running smooth. Just took my time. Sure beats $500 plus for a replacement pump. Congrats again!!! For those who haven't replaced their bearing yet, I highly suggest the next time you have a little extra time (HA!), either loosen the belt tensioner or remove the top alternator bolt (I think) on your car, remove the serpentine belt, and spin all the bearings/pulleys associated with the belt including the smog pump. If any bearing spins slowly, there is still grease in the bearings. If the bearings spins freely, the grease is gone and it is only a short time before that bearing will fail. I replaced the tensioner pulley and grooved pulley on my car at 117,500 miles. The air pump bearing lasted just a little bit longer (131,000). Sure beats getting stuck out on the road with a burned bearing/broken serpentine belt.

EricSilver · #7 02-02-2009, 12:49 PM

Did this same repair about two years ago and documented in a thread here.

The "big" advice I would offer is to loosen the magnetic clutch while the pump is still on the car, rather than waiting until after it is off.

pawoSD · #8 02-03-2009, 01:11 AM

Hmm....this summer I'll have to check all that on our 300E to make sure everything is moving smoothly....so far it all runs quiet and smooth....the belt and tensioner on ours look pretty new (as is the radiator) so I am guessing some work has already been done...

qwkcoupe · #9 06-07-2009, 05:33 PM

Alright folks, I will make two posts.

1) to let you know I now know why I can't read my bearings part numbers... Only the race if left. It measures the same as above. Everything disentigrated except about 2/3 of the bearings. Becuase my bearing fell to pieces in my hand, well, it was a bit tricky, but with WD-40's help, I was able to tap the out race out from the front face of the pulley by hammering at a 30* angle (way off camber).

2) results post

qwkcoupe · #10 06-29-2009, 10:36 PM

Post 2) I bought the bearing from bearingsdirect.com, part number: 32BG05S18G-2DS. The reinstall went well. I was disappointed to find this is a china part. Oh well, nice and quite and for a whole lot less money. Thanks!

glenmore · #11 06-30-2009, 12:07 AM

Is the old bearing just pounded out from the other side?

How easy is it to get the new bearing in? Does sticking the new bearing in the freezer overnight help?

Thanks,

glenmore
1991 300CE
2000 C280

EricSilver · #12 06-30-2009, 07:49 AM

Quote:

Originally Posted by glenmore

Is the old bearing just pounded out from the other side?

How easy is it to get the new bearing in? Does sticking the new bearing in the freezer overnight help?

Drenching the old bearing in wd40 or some other oil overnight helps. Then, just a few taps will dislodge the old bearing. No need to freeze the new one.

See post #19 here:
What is Inner Diameter of Air Pump Pulley? (Need Correct Drift to Remove Bearing)

pawoSD · #13 06-30-2009, 07:56 AM

Another option is to just eliminate the air pump from the car.