Heres a crazy-maker. I’m visiting my girlfriend in the South for the summer and I used the opportunity to buy an old diesel Mercedes. Its already left us stranded several times, but I’m almost done getting the cobwebs out of it and getting a proper old Mercedes.
I just replaced the alternator, after I noticed the battery being drained a few times here and there. The new (rebuilt) alternator works …sort of.
This is the sequence of events. I start the car, and everything appears to be working fine. The battery light briefly flashes when I start the car (along with all of the warning lights), so I know that the bulb is good.
Several miles down the road, the lights start to dim, then the turn signals stop working, and then the radio goes. So the battery isnt being charged… But then! As soon as the lights go totally out, the alternator kicks in, and everything comes to life. This happens EVERY time I drive the car, so I’ve found it best to turn everything on (lights, rear defrost, fan, etc.) to drain the battery as fast as possible so the alternator will kick in and charge the battery for the next start.
Once the alternator starts charging, it seems to charge indefinitely. The wires coming off the alternator are in reasonably good shape, I just polished up the grounding cable off of the battery, and I’m still out of luck.
My girlfriend already thinks I’m crazy for buying the junker, the auto parts guys think I’m crazy, and I’m starting to agree with all of them!