I changed the starter tonight with a Bosch re-manufactured unit.

FYI:There are two 4" long 10 mm Allen bolts holding the starter on (from back to front). In my case, I think they were installed by Satan himself. You will need a 24" extension (or two-12" extensions), a universal, and a 10 mm hex drive.

I tried it first with a 3/8" setup and I gave up trying to loosen the bolts after I twisted the breaker bar over 90 degrees and wondered when the extension would finally snap (and what part of my face it would hit when it did). I resorted to a 1/2" breaker bar, 1/2" drive 24" extension and 1/2" drive 10 mm hex. It took a lot of torque to finally break them loose but it did the job.

Also, there is a small Phillips head screw connecting one of the starter wires to the solenoid. It is difficult to get to with a screwdriver, but a Phillips head bit stuck into a 1/4" drive socket made it much easier. The large wire is secured by a 13 mm nut and is easy to get to. Be careful of the position of any shims that come off between the starter and bell housing.

When taking the old starter out, pay attention to how it finally slips through the steering damper/center link. It will make it much easier to get the new one in if you remember how the old one came out. You may even need to turn the steering wheel to fit it out from below. Most important, make sure you disconnect the battery.

Hopefully this will solve the noise problem.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles