BJ42 12V alternator/voltage regulator help required! (1 Viewer)

[Pommy]

Hi guys,

I’ve been having some dramas since finally registering and driving my car since 18 months off the road.
Battery reads usually around 12.5 ish before starting and when running I’m only getting 12.15 volts with throttle around 2000 rpm and this is causing obvious problems with wiper motor and headlights not performing properly.

I’m assuming this is classic alternator or voltage reg problems so I have been looking for replacement parts which leads to my next problem. The PO has installed a new looking voltage regulator but the part number is for a 2H and 3F engine not the 3B...
Are they the same output and usable on either engine or is this possibly my problem with the alternator not charging? I would prefer to change this out first before stripping down the alternator or looking for a new replacement.

I’m hoping the alternator is actually originally from a 3B too as I just don’t trust anything is original on this rig!

Any advice would be great thanks guys!

 

[Splangy]

The alternator and regulator don’t have to be from a 3B for them to work properly. They do, however, need to be compatible and need to be wired properly. I’m assuming this is an external voltage regulator and not the internal type (built into alternator) used in later 3B’s?

 

[Pommy]

The alternator and regulator don’t have to be from a 3B for them to work properly. They do, however, need to be compatible and need to be wired properly. I’m assuming this is an external voltage regulator and not the internal type (built into alternator) used in later 3B’s?

Yes that’s correct mate, the regulator itself looks very new so I’m pretty sure it’s the alternator at fault. I was hoping to find an alternative alternator that works just as well so I could swap them over in an hour and be on the road but I can’t seem to find much info out there of people who have done it...

I think I’ll have to take it off and pull it apart for a rebuild by an auto electrician unfortunately