1973 BMW R75/5 Rebuild: Replace Alternator Brushes and Front Crankshaft Seal

I had replaced the leaking camshaft seal earlier and you can read about how I did that here:

The alternator has 97,500 miles on it, so I decided to replace the brushes.  I hadn’t seen evidence of oil leaks from the front crankshaft seal, but it turns out its very easy to replace it when I was replacing the alternator brushes.  I also cleaned the rust and flaking paint off the starter motor and then painted it to stop any further rusting.

You can read about what I did on both of these tasks here:

I bought the brushes at Euro Motoelectrics which is here in Denver, CO.  I also picked up a hardened bolt to extract the alternator rotor from the tapered nose of the crankshaft.

Rotor Puller Bolt and New Brushes

Rotor Puller Bolt and New Brushes

These jobs went pretty quickly and were straight forward.  I found I needed a  200/260 watt soldering iron to remove the old solder and solder the new brushes as they are soldered to a large plate that dissipates heat pretty well.  My 140 watt gun wasn’t up to the task.

Old Brushes Removed from Holder

Old Brushes Removed from Holder

New Brushes Installed

New Brushes Installed

Shaft Seal Puller Installed

Shaft Seal Puller Installed With Adjustable Pivot Pin Resting on Engine Housing

At this point, the engine work I planned is done.  Here is the painted starter motor installed and the engine after polishing up the cases.

Painted Starter Motor Installed

Painted Starter Motor Installed

Polished Engine

Polished Engine

Polished Engine

Polished Engine

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