Need some ideas the 83sd has been having alternator problems, first alternator lasted 147000 miles. Then replaced with remans. from napa, then this one fryed the battery to much voltage. then another battery and alternator, this lasted two weeks and started to boil the battery dry. I changed the alternator this lasted one month and the battery lite stays on now when the key is off. Going to do a volt check on alternator while car is running to see if its the alternator but i think it is. I have cleaned the ground on battery, grounded the battery to the engine. The only good thing is all alternators have been free and i can change one fast!
Bill

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94 dodge cummings,86 ford 6.9,75 mbz 240d[ sold], 82 mbz 300sd,83 mbz 300sd

Learn to put brushes and bearings in an alternator, find a good one and stick with it.

Guess: You will need another battery.
Guess: The rebuilder does not know what they are doing.
Over charge = bad regulator..
Check engine to body ground cable, if in doubt, replace it.

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1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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This summer I went through the same problem. Replaced the alternator, 4 months later, same thing, then the last one after one week.

Every one of them the same thing, diode failure. Cheap rebuilds.

Make sure that you are disconnecting the battery when you do the replacement. (I did this each time but still had problems.)

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Sam

84 300SD 350K+ miles ( Blue Belle )