The DVM is connected to the amature winding to ground and indicates there is a short to ground (it 's reading 11.1 ohms). A good armature should be infinite ohms. Notice the darker color (from excessive heating due to the short), compared to the good armature on the left.

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Stay away from auto zone starters! I got stuck with a "lifetime" starter from "those people" They only last about an average of 10 months before the chineese replacement parts fail. I went through three of them myself. they worked good for a while and then something would give out. Your much better with a salvage starter or having one rebuilt for you by someone that uses quality parts. The last one i got I disassembled, found a used German Bendix And a new German solenoid, put in a set of used Bosh brushes, and am now good to go. Two years down the line and it starts great.
Jon J
81 240D

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Jon J.
81 240D

I did, after reading about many failed rebuilt lifetime guarantee starters. I "rebuilt" it myself, which amounted to de-carboning the commutator and brush assembly, checking the bushings/bearings are not worn, lube and bench test before install.

I just "rebuilt" my 240D parts car starter with 181K miles, which is interchangeable with the 300D turbo starter per a local rebuild shop. I took a video of it being bench tested. It's drawing a little under 100 amps with a no load rpm of 8300 which is within specs. It will be a spare starter for the 300DT. I hope I will not be needing it for a long time.

CLICK TO PLAY!

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

FWIW I have had an Autozoo starter in for almost two years now with no problems.

I have had it get "stuck" ONCE, where turning the key back off then on will do the trick.

If it ever goes, I'll be replacing it with a Bosch.

Getting "stuck" is not normal. Do you think it was the starter solenoid that was stuck or the ignition switch?

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Starter solenoid. I'm aware that it's not normal, it just hasn't happened enough for me to be worried about it.

If it starts getting more consistent I'll look in to it further, but at this point I'm okay with it.

Your starter comes out so easy on your NA that I'd suggest taking it out and follow Army's exc photo DIY and do a clean and lube yourself. My guess is they forgot to put grease on the solenoid fork and centrifugal clutch spiral gear. The solenoid cylinder should be left dry. I've taken 3 of these apart now and it is very easy. Make sure you use a good impact screw driver (hammer type) on the 3 solenoid screws otherwise you'll be drilling them out

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I took the shorted armature (on the right) to the rebuild shop for the owner to have a look. He had told me that it is very unusual for an armature to short out. He put it on his test set and applied voltage to the armature and slowly cranked up the juice till the meter moved and there was a spark. Sure enough it is shorted. He looked closely at the armature and pointed out the shiny 1/16" ring on the top and bottom of the core which can be seen in the pic. Apparently the worn bushing allowed the armature to rub on the field coil and this caused the core to deform enough to break through the insulation on the magnet wire and caused the short. I also wanted to buy a new bushing. When I asked "how much" he said "don't worry about it" and gave it to me.

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I've come across that same kind of kindness - it seems to me that people who really work for a living recognise a fellow "worker" and do their best to help them out.

Well done for saving another starter motor!

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!