just bought my life long dream sat. at auction. has elect. problem no gages work water,oil,fuel no turn sigs or brake lites.also runs bat down over nite. also no tach or speedometer thanks Bobco

Replace the battery first, and if that doesn't help, take a look at the alternator.

Replace all fuses with new and start there. It sounds like you will be unplugging things like the antenna and radio to find a draw.

thanks for help on 300sd turbo diesel
 

ok guys heres what i did. first i replaced the batt. so i guess the alt. is next but got the problim of no gages,turn sig,brake lites fixed with fuses. now ill work on tach and dash lites and ac.many thanks for the help hope i can help some one some day.Bobco faded out 1982 300sd turbo diesel. but were coming back

Let's check a few things first
 

Greetings Bobco,

Is the radio/stero aftermarket, if so it's probably turned on and draining the battery overnight. Many have wired them to stay on even with the car turned off. The gage problem, needs to be traced from the connector located on the back of the dash. If you have a Haynes manual for this vehicle, it will make it easier to trace where the wires are going to and whether they are finding a ground to drain the battery through an accessory left on. The alternator can also cause the problem if one of the diodes has gone bad allowing DC current to flow in both directions, thus draining the battery overnight. Try unplugging the alternator overnight and see if the battery goes dead. Remember to replug the alternator back in before starting the engine otherwise the current has no place to go and damage can be done to this critter.
Just some suggestions that are electrically common sense.

Charles