Electrical Weirdness Attacks 300D
 

Been having a slew of electrical weird things happen since my alternator went out. Not just went out like died, but I put a DVM on the battery when it was running, and it read almost 17 volts. Enough damage was done to split the MB battery down the side. Now for the weirdness.
When I put on the blinker to turn left, the wipers go into intermittent mode. I was thinking the blinker stalk might be getting worn out. Well, not the stalk itself, but the switches in the column. To the right is fine.
The temp gauge and the fuel gauge will jump about 3/8" for a few seconds, and then go back down. Usually when it does this, the seat belt warning light will illuminate.
I hate weird electrical stuff. :mad:
Tonight I'm going to redo the ground, since those have been known to cause weird things to happen.

Pull the instrument panel and trace the circuits. My odo reset arm fell off the odo and was jangling around in the panel shorting all kinds of things... Jumping gauges is usually bad ground circuit in the panel itself....

Over Voltage
 

1984 300d Turbo 141,000
Replace The Regulator $28.00 On The Rear Of Alternator Or New
Alternator Diy, Overvoltage Need To Be Under 14.5 Volts Max

My wierd electrical problems and jumping guages were due to the Engine-Chassis ground being loose.

I've had the following things go wrong and caused electrical problems:

1. The instrument panel not being grounded. Was intermittent. Took a wire and grounded it.

2. Lots of voltage regulators gone bad

3. A wire between the alt and the battery wore down and the copper was exposed. Did a number on the battery and alt and VR. Blew through a couple of VR's before I found it.

Hope you find it

dp

Took an alternator off of my 82, and it's working fine. I have a VR on order for the other one.
Another reason I think the stalk is bad I found out tonight, when I hit the high beams, the wipers go into intermittent.

The gauges were fine all the way home, and now that I think about it, when they jump it's when the temp gets over 100C. Still working on that one, I believe it's the water pump going. Tonight all the way home, it never got above 85.

Tony I just had the same thing happen on my friends 240 I had mentioned I got the alternator for. The original had coolant dripping on it and it seized once so we decided to replace it. I had put a new voltage requlator on it a year before, it was still working good. I had another alternator in the garage at home so I tried that first, swapped the pulley and VR to the other alt and put it in, it was charging...too much. 17+ volts. This was with the good voltage regulator on it. ran an alt test and it failed it. Thats why I went ahead and got the new replacement alternator.