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Is there a specific amperage rating for an alternator in a 1980 300D? if so what is it? also any input on what brand of after market alternator one should by as a replacement?
 

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1984 Mercedes-Benz 300D Turbo Diesel
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So, photo shows a 55amp alternator that was installed on My w123 1984 300D Turbo Diesel. It went bad. In april 2019 I bought POWER SELECT 13056N , 55 Amp alternator on rockauto for about $80. Installed it and it works. Although I don't think I like it. I have this intermittent problem when I would smell something like burned plastic or burned wiring insulation coming from under the hood. When it starts smelling like this I'd stop the car and try to locate the source under the hood. I thought maybe it's alternator belt because it's slipping and whining a lot. I was unable to locate the exact source of this smell, but I think this comes from the alternator. It only happened on the hottest summer days in heavy city traffic when the temperature under the hood would be the highest.

My old alternator had a 2-belt pulley. The new one has 1-belt pulley. 1 belt is not enough -- it just keeps slipping and whining periodically. So I need to install 2-belt pulley.

Hope this helps.
 

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1982 300CD
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There is a Saab alternator you can use, iirc. 110A or something crazy. I was thinking about it, but never ran into troubles with 65, even with a decent system. I'm sure you could find it if you do a search.
 

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Thanks for the input ... is there anything tricky about changing out the alternator on the 300D ? ...I have never done it before and was considering doing to myself ... looks basic but don't know ... thanks
 

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1984 Mercedes-Benz 300D Turbo Diesel
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Thanks for the input ... is there anything tricky about changing out the alternator on the 300D ? ...I have never done it before and was considering doing to myself ... looks basic but don't know ... thanks
No, nothing tricky, quite easy. It is invonvenient to work with alternator while on your back and untder the car. 1 hour should be more than enough to replace the alternator. One bolt unscrewed from the top and one bolt from the bottom. To put new belt on, you need to remove other belts first.
 

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I am hoping to get around to addressing my alternator issue this week but before I go buy a new one does anybody know if there is something else that can be affecting my alternator causing it not to make a charge ? .. the reason I am asking this is the present alternator was changed out maybe 15 months ago and I don't drive this car that much ... also when it failed last time my battery light came on ... as its done in the past when my battery was bad etc. ... its definitely not my battery this time around as it is holding a charge and the tests show the alternator is not working...so I'm just curious if there is something else I should look at before I switch out the alternator... thanks
 

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1985 300 TD 1981 300 SD
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Could be a bad voltage regulator which is on the back of the alternator, I'm dealing with a crapped out year old voltage reg on my 126, it left me in the dark last night when I went to pick up the wife from work.
 

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1984 Mercedes-Benz 300D Turbo Diesel
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Could be a bad voltage regulator which is on the back of the alternator, I'm dealing with a crapped out year old voltage reg on my 126, it left me in the dark last night when I went to pick up the wife from work.
I would not mess with voltage regulator (i did -- it was pain).Whole alternator is cheap to just replace it. I bought Chinese aftermarket voltage regulator, and then I am not sure what happened -- either regulator was faulty or I instaled it incorrectly -- alternator shorted. I ended up buying new alternator anyway.
 

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There used to be a California seller on eBay, Eagle Electric that sold 80 am alternators that were the same size and you the regular electrical connector worked with it.
If I recall correctly it comes without a pulley on it. However, you can contact them and request a pulley which would likely increase the price.\
I have the 55 amp alternator on mine and it has been entirely adequate for running what came with the car and charging the batter.
 
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