Author Topic: 60A alternator in a '92 1.6L Jetta? (Read 2140 times)

larry104 · « **on:** March 06, 2009, 06:52:27 pm »

A '92 Jetta Ecodiesel uses a 90A alternator. I think the drive belt is undersized for the hp draw. It's not a great setup to begin with because tightening the tensioner reduces belt wrap angle about the alternator pulley. I don't recall ever having to tighten an alternator belt to the level I do with this setup to keep it from slipping. Just curious, has anyone tried putting a lower-output alternator on an Mk2 1.6 L diesel? I think the gas-engine alternators are 60A? Or, is there a clever way to lower the output of the 90A unit.

TurboJ · « **Reply #1 on:** March 07, 2009, 02:24:55 pm »

60A alternators were used on factory TDs and I remember even some 45A ones. Just swap one over.

subsonic · « **Reply #2 on:** March 07, 2009, 02:27:01 pm »

What is on your car for accesories needing to draw power? A/C, massive sound system and speakers etc?

Vincent Waldon · « **Reply #3 on:** March 07, 2009, 02:53:37 pm »

One thing to keep in mind is that the alternator's rating is the maximum current it is able to put out... not the current it puts out at all times.

This means that if your car only needs 20A to operate that's all the alternator will put out... regardless of what size it is.

So... no need to "lower" a 90A alternator, other than to not ask it to deliver 90 amps !! And, as luck would have it, diesels by nature draw less current than their gasser cousins.

One other thing to keep in mind... although gasser alternators may fit they will likely be missing the W-terminal that the diesel chassis needs to run the oil pressure warning system and tach.