I'm working on my 82 300sd. 2 weeks ago the starter started getting stuck on while the engine was running and would miss every few starts and just go "jinnnnng," yet the car was starting, only it took awhile to get it to start. Anyway, I replaced the starter with a a reman one in which the old numbers crossed over to, now the engine seems like it cranks over way too slow to start. And it doesn't start. My question is if anyone could understand this reason?

I actually have a dual battery setup, but the auxillary silenoids don't come before the starter as the positive lead from a single battery goes directly to the starter silenoid. I have jumped the starter directly and it still turns over very slow. I have cleaned my ground strap on the starter. I tested all the relays and voltages of the batteries and they are fine. So I took my starters to have tested at autozone, both tested fine (in actuality I know the old one messes up, I just tested it to see what it would pull) but I know this test can be faulty, as a starter under a load (especially this load) is a different story.

I currently am connecting a 50 amp booster along with jumper cables from my pickup and it still is not creating enough power to start. The engine eventually knocks hard when turning over, but never 'starts' and doesn't run.

And another thing, the previous starter literally rocked the engine like I rock polyester. Hard. This one seems weaker. ?????? I am stumped.

Any clues would GREATLY be apprectiated, as this is is very redundant, mainly because I just got the car a month ago...and I want to drive it!

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