I'm planning on upgrading the wimpy 75a? alternator on my SDL with a nice 115a one. VW diesels with 90+ amp alternators have a one way clutch on the drive pulley so that as you shift, etc, the alternator isn't trying to drive the engine. This saves wear on the harmonic balancer and the drive belt. Early TDIs and 1.9l IDI engines have problems with the crank sprocket coming loose / ruining the crankshaft, and putting a clutched pulley on the alt helps mitigate that.

Would it be worth installing one of these on the Mercedes? I haven't heard about issues with the crank bolt / balancer, but it would be easy to do if the VW pulley is the right length...

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.