3B alternator differences

[Chang-kuao-lo]

Ok, the alt. in the NZ '83 BJ42 went and siezed all of a sudden. I got a call with "the landcruiser is making a horrible noise, and the 'filter' light is on.", the horrible noise was the belt squaking its' way over the non-turning alt. pulley. So, tearing my hair out wonering who might have a 3B alt. handy, I remembered that I have a whole engine sitting in a crate, alternator and all . So I put this alt. on the unit with a bit of finnagling. And the damn 3 wire plug on the alt. won't fit, some sort of style change in the plug, so I made a wee harness to fit it. It starts up, and promptly shuts down. A few times. Oh look, a fuse is toasted (I'm not sure which one since the box cover is long gone). Fresh out of old school glass fuses. So I put a jump lead across it, and it ran (I think the fuse has something to do with the edic thingamagig). Shut it off real quick when the wire got real hot, and the "filter" light stayed on.

So, what could this be? An internal voltage regulator vs. external (which my '42 has)? The engine may have come out of a Canadian spec 40 series. last minute thought, perhaps a 24V alt. (the idiot lights didn't seem overly bright though)? I'm pretty sure the seller said it was a 12V engine. The other weird thing is that the alt. I pulled from the '42 didn't look like a Toyota alt., it had a 4 wire plug with a patch-plug that took it down to 3 wire (wtf?), it's off to the auto-electric rebuilder either way.
Ideas anyone?

 

[cruiser_guy]

If it's a Canadian spec 12v 3B then it is a BJ60 engine and it has an internally regulated altenator.

 

[Chang-kuao-lo]

So, that would mean that theres some competition between the two voltage regulators? I guess my best bet is to wait until the original alt. is rebuilt.

 

[cruiser_guy]

It would make sense with the three wire plug on the altenator. That's what the BJ60 has.

You can easily tell by removing the brush cover. The internal regulator is right below that on the internally regulated altenators.

 

[Chang-kuao-lo]

They both had a 3 wire plug, just a different style of plug. Perhaps I'll take a look later, I suspect that the voltage regulator(s) is the problem. I guess my voltage is being over-regulated...

 

[jake2far]

What seized, a bearing or your vacuum pump? If it is the bearings it is really easy to replace your self, if it is the vacuum pump the alt rebuilder might have a problem solving it.


Jim

 

[Chang-kuao-lo]

Vac pump is fine, I took it off first. Don't mind sending it to the rebuild shop, it'll come back clean as a whistle with new everything. Worth the extra $, besides he'll have everything to test it out and catch any problems I might miss.

 

[smack]

hey had the same thing but diodes came off the neg rectifier
plate so while that is being done up i had 2 bolt up a 2H alt with
internal reg my BJ42 has external.
What u got to do is unplug the ex reg and and find the wire that
has positive when key is on and nothing or only slight when engine is running thats your battery light or ammeter wire
then run that wire to the positie wire which comes out of the positive rectifier plate.. that should work..

cheers..

 

[seapotato]

hey had the same thing but diodes came off the neg rectifier
plate so while that is being done up i had 2 bolt up a 2H alt with
internal reg my BJ42 has external.
What u got to do is unplug the ex reg and and find the wire that
has positive when key is on and nothing or only slight when engine is running thats your battery light or ammeter wire
then run that wire to the positie wire which comes out of the positive rectifier plate.. that should work..

cheers..

I know this thread is somewhat ancient, but it's the closest I could find on my search.

81 bj42 24v, just had my batteries crap out, and I'm suspicious of my alternator.

Haven't done much testing yet ( raining too hard yesterday) but I will once I'm finished my coffee.

In case the stock alt is hooped, I have an alt from a 24v bj70 out in the shed. Likely internally regulated.

Any other thoughts on the above procedure being correct for getting it to work?

Could be mine is fine, and it's just crap batteries, or something easy like brushes, but figgered I'd get the ball rolling first.

Either way, it'll be nice to know how to hook up the spare.

cheers,
ryan