Hey folks, first time posting, newbie mechanic, just bought a pair of these 1981 300sd turbo diesels, one a (previously) running parts car, the other hopefully a runner, my first cars in 4+ years, my first mercedes, and my first diesels. So, here's my problem.
I threw some diesel performance boost (I forget which one) in my tank, filled it up, drove it home about 10 miles, parked it, and the next day it wouldn't start. It's cranking, but upon multiple attempts the battery started dying. The battery is supposed to be new but would multiple attempts really drain a battery that quickly? It turned cold quick this week, down to the 20s at night, so I'm hoping it has nothing to do with the fuel.... hoping. BUT, I haven't replaced any filters or anything yet so maybe it just loosened up some gunk and I'll fix it when I replace all of the filters.
I'm looking at the alternator, took two days to remove the voltage regulator because the head started to strip. I got it out and it doesn't look terrible but it doesn't look good either. I had to break the plastic to get the screw out so I'm replacing it regardless. I read that if that goes it can kill the glow plugs and relay, which were replaced when I bought the car, which makes me think regulator. Then I notice, there's a chunk of wood jammed behind the alternator. Could a bad alternator adjustment bolt be the reason someone did this? I couldn't quite figure out where the bolt is supposed to be.
Also, one last compounding factor, I replaced a handful of worn fuses last week, and the lights in my instrument and control panels started working for the first time, very intermittently. Could a short be the cause of that much battery drain?
Thanks for reading.
~Brian