For the last 6 months or so the heater blower motor has occasionally been squeaking. A few days ago it was clearly getting worse. Time to do something about it.
Seeing as I am a cheapskate, I didn't really want to spend the money to buy a replacement unless it truly needed to be replaced. In a 123, the blower is so easy to get to I didn't mind the prospect of getting to it repeatedly. I pulled it out thinking I'd try automatic transmission fluid to lubricate the bearings. But the front bearing is behind the impeller. Since it is the one hard to get to, I expect it is the one making noise. I pulled the motor from the housing, thinking pleasant thoughts about Mercedes for building these assemblies such the _can_ be dis-assembled! The impeller is just press fit on the motor shaft, so one the housing was off it was easy to support the motor by the impeller and with a drift punch separate the motor from the impeller. That was the end of the easy part. The motor itself is not held together with screws or bolts. The bearing supports are staked or swaged to the side. Using a cold chisel and a drift punch I bend bake the swaging and removed the front bearing support. The commutator was so worn by the brushes I had to retract the brushes a bit to get the armature out. The magnetic field was also keeping the armature withing the permanent magnet field. I smoothed out the commutator a bit, used emery cloth to be sure the bearing surfaces were smooth, greased the shaft, and put it all back together again. I used a cold chisel to re-swaging the case to hold the bearing support. This was a bit tricking as the metal didn't seem to like being bent a repeatedly. I think it will hold - for a while anyway. The motor ran quiet when I tested the motor before putting it all back together again. After re-assembling and re-installing the blower it was still quiet. Then the real test - a four hour drive. Quiet the whole time. So I don't expect this is a truly long term repair as the shaft at the bearing was pitted and the brushes are fairly worn. But maybe I'll get another couple years from it. -- Philip _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com All posts are the result of individual contributors and as such, those individuals are responsible for the content of the post. The list owner has no control over the content of the messages of each contributor.