1995 E320 wagon, 188k miles. Heater blower/fan is not blowing much air. BUT, on a hard right turn, the fan speeds up greatly for the duration of the turn. Seems like centifugal force, right turn only, improves fan speed dramatically. Could it be water in an air-box? Bad bearings? Any ideas?
Thanks, Paul T

Perhaps the motor brushes are worn out? Unless you hear grinding or knocking noise the bearing should still be OK. Brushes are replaceable if you can use a soldering iron. Beats the alternative of buying a new motor.

I took mine out recently and the blower enclosure was full of leaves. This caused a flapping noise. The blower was also working intermittently. Turns out it had whatever they use for insulation under the dash wrapped around both of the motor shafts inboard of the fan cages and it was binding the whole thing up under current. Apparently that stuff gets sucked up into the squirrel cage and winds itself around the shafts. I wouldn't be surprised if that's the cause of a lot of burned out motors. Brushes were fine so I put a drop of trans fluid on the shafts at the bearing and hit the commutator with some contact cleaner. Works like it should now.

Try jiggling the switch as well, it might be worn out. These blower motors will need for you to check on them every ten years or so. It's not difficult but you do have to remove the wiper to get at it.

__________________
'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)

Thanks for that, D.
It seems so odd that the fan revs right up the instant i throw the car into a right turn: Revs up instantly with the turn-in, and continues to rev high as long as the centriugal force / turn is happening. Straighten out the wheel and the fan speed drops right off. With the road noise at speed, its difficult to hear, but there is no grinding or squeeling; just a very low motor boat sound.

yours has a regulator and might have a dust filter as well, may want to check those out

__________________
'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)

My first suspicion would be the bushings need lubrication, and/or the filter is plugged.

You will need these links.

W124 Blower Motor Removal Photos
W124 Blower Motor Removal Photos - PeachParts Mercedes ShopForum

MONO BLADE VERTICAL parked windshield wiper
windshield wiper

Hesitating Wiper Repair
http://202tech.mkosonen.com/howto/wiper.html




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Very helpful. I assume the 1995 blower will be similar to the 1990 coupe.
I don't know what to expect. I have no squeeling, screeching, and the centifugal force of a right turn causes an instant increase in blower speed. I will report back after I have had a chance to go in there.
Thanks again.