I have a problem with my peugeot 205 TD from 94. I had a diesel leak from injector return lines. I just fixed that but it seems like my alternator broke, again, it's like the third one in two years and I saw some people on internet blaming diesel leaking on alternator for cause of malfunction.

So, I know my alternator just died. 12.5V when engine is running, 6/7V on exciter and my battery dash light is slightly on (less than the other ones) at engine running AND off.

So, I would like to know what the diesel is destroying on an alternator (charcoal ?) in order to repair it if possible with a repair kit.

Thank you!


I wouldn't think diesel would cause any issues with the alternator, for the main reason diesel is an oil, which would lubricate if nothing else. It has detergents, but should be non-caustic (or acidic or what have you). I'm not a chemist, so I don't have all the answers here, but I've never seen nor heard of diesel having the effect you're talking about on any parts. I'm wondering if there isn't a systemic problem with the part itself.

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    AFAIK, diesel is non-conducting, so it could cause the required conductivity between the rotor and the stator to go away due to a thin diesel film in the moving contact points, and causing poor field excitation. However, I believe the alternator could be disassembled and repaired in this case. Gasoline, in fact, could be a good way to dissolve the diesel, although I would use better solvents in the repair. – juhist Aug 5 '17 at 13:34

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