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Alternator replacement

Discussion in 'E36 (1992-1999)' started by Arthur B Fisch, Mar 2, 2010.

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    Arthur B Fisch

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    Do anyone have any experience with changing the alternator in an E36??? I would like to know if a 140A can be replaced for a 90A??? Are they any fitments problems as the 140A looks a little bigger?? Are the bolt patterns the same??? Do the voltage regulator need to be changed.

    I have added a moderate size amp for a sub-woofer and I might add an auxillary electronic fan in the future.

    thanks.

    abfisch
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    • Technical Service Advisor

    mooseheadm5

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    It can be done without clearance issues and they should have the same bolt patterns. You may need to change the tensioners as well, though, as different alternators had different tensioner setups. THe regulator is internal to the alternator.
    • Member

    Arthur B Fisch

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    Thanks

    Thank you for the nice and quick response. I just posted this not 30 min. ago. When you change the tensioners, do you mean replace or just get the correct tension on the belt?? I just replaced all the tensioners last year. The car had 97K on it??

    If you had a amp for a subwoofer and wanted to possibly put in a bigger aux fan down the road, but that was it, would you use the same 90A or go with the bigger one 140A??? I performed a fan delete kit on the vehicle and it works very well. I don't do much city driving however.

    Thanks a whole bunch.

    abfisch
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    • Technical Service Advisor

    mooseheadm5

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    Some tensioner setups are mechanical:
    [IMG]
    Some are hydraulic:
    [IMG]
    I don't know which alternators came with which tensioners or if they can be swapped- I have never tried. You may not need to worry about it, but I just thought I'd point it out.

    Before jumping to the larger alternator, check your charging voltage with the accessories running (interior blower fan on high, headlights on, stero blasting.) If it drops too low now, you would want to upgrade, otherwise you can wait and see what happens to the charging voltage after the stereo install.
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    az3579

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    Based on the way you worded this, it seems like you want to downgrade from a 140A to 90. Is this really the case? I wouldn't recommend doing this, if that is what you're looking to do...

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