Hello everyone... I had the opportunity / need to replace my compressor clutch bearing since it was making grinding noises. The repair shop said I needed to replace the whole compressor (I thought it was too much parts+labor+a/c evac and recharge for my comfort). Anyway, knowing that the system is sealed and you do not NEED to evacuate the system, I gave it a shot. This is for the Bosch Behr wingcell compressor. The bearing can be obtained from autozone via the web for about $15. Advanced auto actually had one in stock for $27.
1) remove a/c v-belt
2) remove 12mm bolt in center of compressor clutch
3) use clutch removal tool threaded into center of clutch hub (if you can find the right one) or use wooden shims around the perimeter of the clutch between the friction surfaces. You may have to alternate between 3 separate areas to both insert and spread the clutch away from the pulley. Total distance before it comes off is about an inch or so. I had to use 3 shims wedged together at three different areas before it came loose. You may have to drive the third shim between the first two to spread the clutch away from the pulley. I used a hammer and flat blade to assist with installing the shims. When removing the clutch, capture the spacer and any washers / shims that set the clutch gap. Be patient and do not bend!
4) the pulley is held in place by a sleeve nut about 1.25" in diameter with compression fitting beneath. The nut is circular with 4 tabs cut into it at 90 deg marks. There is likely one tab of the compression fitting which is bent into the tab of the sleeve nut. This should be bent back into the pulley which will allow the sleeve nut to unscrew. If you don't find it, you'll just have to unscrew harder.
5) loosen the sleeve nut with a well placed flat blade in the tab of the sleeve nut and hammer. After it is loosened, it can be removed by hand. Capture the sleeve nut and compression fitting.
6) remove the pulley either by hand or gently with a hammer. Now would be a good time to clean the coil and other parts of the compressor with a rag / solvent. Also a good time to clean the clutch and pulley before reinstalling a new bearing.
7) there are two compression rings holding the bearing in place. Remove.
8) press out old bearing and then reinstall one compression ring. Press in new bearing. If you have a press, great. If not, visit a machine shop. Reinstall the other compression ring.
9) reinstall is reverse of removal. I had to use a hammer to gently install both the pulley and clutch.
compressor clutch bearing replacement explained
This is a great write-up however pictures would be very helpful given that most of these parts and procedures are not something your typical E28 owner or typical E28 repair would encounter. Thanks for taking the time to write it up. It would be very valuable to those who still have R12 in their system (like me) and have a bad compressor clutch.
I have a short video of one I had already removed from a donor car; however, based on the location of the activity and that the compressor is not removed from the car, it makes it hard to capture. It's actually pretty simple. Took less than an hour if you don't count having to get the bearing pressed in/out.
Sorry to be a spoil sport but ANY prying on the clutch rim will almost guarantee you wind up w/ a bent disk and ready for the trash if it's tight at all. Pushing it off with a tool made for it is the only real way unless you come across one that is loose on the shaft and just slides off. (not uncommon)
Even the correct tool needs a steel dowel about an inch long stuck down in the retaining bolt hole to give the tool pressure-screw enough travel.
Considering you have to probably remove the hub a second time to set the air gap, plan to start w/ tool in hand. Also, hubs are harder to come by than bearings.
-Dick
Even the correct tool needs a steel dowel about an inch long stuck down in the retaining bolt hole to give the tool pressure-screw enough travel.
Considering you have to probably remove the hub a second time to set the air gap, plan to start w/ tool in hand. Also, hubs are harder to come by than bearings.
-Dick
you're right... just replace the compressor.
compressor clutch - $135
compressor - $350 + evac and refill from ac shop
bearing + machine shop - $30-50
in the event that you damage the clutch, you are still in a better position than when a shop which has suggested a compresor replacement.
merely trying to provide people options. obviously, if you are not careful, you could bend the clutch, but I was successful, so seems reasonable to perform
compressor clutch - $135
compressor - $350 + evac and refill from ac shop
bearing + machine shop - $30-50
in the event that you damage the clutch, you are still in a better position than when a shop which has suggested a compresor replacement.
merely trying to provide people options. obviously, if you are not careful, you could bend the clutch, but I was successful, so seems reasonable to perform