Several years ago, I was able to separate the motor from the fan, replace the brushes and lube the bearings in an '80 300D, but there have been several redesigns and the later fans are pressed-on, brushes not accessable.

I couldn't inspect the brushed, but at least I was able to get some lube up into the blower-bearings on my '82 240D. That, and making sure my blower fuse contacts are tight, clean and attached to a ceramic fuse, means no further problems (so far!).

And last year, I got lucky on 'half-price-day' at the Virginia Beach Pick-N-Pull. Got a complete heater-AC box, with evaporater, heater-core, blower and controls out of a '79 or '80 240D for $12. And someone else had already removed the dash and unbolted the unit so all I had to do was separate some wires & cables and carry it out. Maybe it has the early-style 'repairable' blower too.

Happy Motoring, Mark

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DrDKW

I've lubricated the blower motors too, but I've never torn one apart. The lubrication only seems to last a few months, so once they start squeaking it just a matter of time. I think my 300D is on it's third blower motor. The last time I replaced the PBU, I also replaced the blower and the aux pump (the pump was probably OK, but I didn't want to risk toasting another PBU. Oh well, as long as the parts are still available I won't complain too much.

I've used power steering fluid or ATF as a motor lubricant. Seems to be more stable under temperature extremes. Unfortunately, if the bearings are really cooked, no lube will last.

There was a thread here awhile back titled "I Lost it All", where some suggested wiring inline fuses directly to items like the blower and aux-pump on ACC models, to prevent burning the PBC unit.

Happy Motoring, Mark

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DrDKW