There is power at the starter, and after everything that would tell me it's the starter. The previous owner said he had it bench tested and it was good.

I'm not very trusting of an aftermarket starter. It started just fine in the begining and has slowly dwindled down. The P.O. Said after he added a new ground it started like a champ. I'm thinking they may of been a coincide. One of the grounds wasn't fully crimped and slipped out when I bumped it. I replaced that ground with a solid 4g wire. The wire that was acting as a ground tested 5ohms and the replacement wire tested .3ohms. Im gonna run a test harness directly to the battery. If I get nothing it has to the starter.

Usually clicking starter means not enough current is getting to the starter. Are you sure that the batteries are fully charged? You should have 12.6V measured across the battery terminals.

You could have bad contacts in the solenoid but it is usually low battery or poor connections in the main cables. Clean the battery terminals & ground. Measure batery voltage & report back.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.

Check that your battery cables are good too..they could be 20 something years old..if they get too corroded they won't work..
I had this happen on a car once
Wont tapping on the starter motor sometimes make it work?

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With power at the starter, and after all the diagnostics you have gone through, it's a bad starter.



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X2.

I agree. I have been through this. replaced starter. A few months later, similar issue. Swapped starter under warranty, 2 years now, no issues.

And unless MBz is making new starters.....they are all going to be aftermarket.

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83 300TD (need rear wiper assembly dead or alive)
84 300SD Daily driver
85 300TD almost 400k miles and driven daily.
98 E300D *sold
86 300SDL *sold and made flawless 10 hour journey to new home.

This week I had a new starter fail after two days. My indy installed one on Tuesday (the previous one had failed to engage on the first attempt a couple of times). On Thursday something internal failed so it kept turning after the engine started (and after I turned off the key). I had to disconnect the battery cable to stop it, and it would then spin (but not engage) if I reconnected it. He replaced it Friday, now it's working perfectly.

Sometimes new parts fail.

Thank you all for all the insight. I ran the starter to the battery directly and sure enough the starter would not spin nor click. The starter is faulty.


When I said I didn't trust the aftermarket part in my previous post it was because it's some generic auto parts store replacement. I much rather use a rebuilt Bosch, which is what I am doing in the next couple of days.


Thanks again guys!