24V Wiring Harness and Other 24V Specific Parts Sources (1 Viewer)

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Location
Columbia, SC
Hey Cruiser family!

Long time reader, fairly new member, first time poster.

I landed a Japanese import 1978 BJ40 RHD last December and haven't had any trouble out of it until recently. It's stopped charging it's dual battery system all together, and after troubleshooting the basics I had the 24V alternator rebuilt. When that didn't cure the issue, I went to the external voltage regulator. Before I broke the OEM VR down, I decided to check all connections. I seem to have quite a few free connections two of which don't have "homes." After re-securing the rest, I got a positive charge on the Ampmeter while idling. I got half a day of celebratory driving before the charging dropped off, lights went out, and the heater faded. That sent me back to the drawing board.

During further inspection, I found quite a bit of a hack-job here and there in the wiring harness that has frustrated me to no end. Since winter is coming, the BJ40 is going to get torn down to fix body and frame issues, I've decided to eliminate a Japanese fisherman's creative fixes by replacing the wiring harness. After quite a few Google searches, I'm coming here to ask a few questions:

1. Where can I source a 24V RHD wiring harness? Factory or otherwise, I think it'll solve a lot of headaches in the later phases of the restoration. Since it's all coming apart, I'd rather have it go back together again without the butchered harness. I don't care if it's a US vendor or shop, or a foreign one, so long as they have or make BJ40 RHD wiring harnesses.

2. Is there anyone out there who rebuilds 24V Nippondenso Alternators, 24V Starters, or even the 24V voltage regulators? I've searched Google, forums, and even other Toyota groups and I've not come up with anything. There's a lot of "Yeah, I sent mine off to get rebuilt", but no one throws out any names of vendors or shops who perform such services. I'm also just smart enough to know that electrical isn't my forte. I know I'm not the only BJ40 B Series in the Continental United States, so there has to be someone, somewhere that provides some BJ40 B Series related services. I would love to know who, if any of you know.

3. Have any of you tried or know anyone who's converted their B Series to the Diahtsu 24v internally regulated alternator? I'm considering this as an option and would like to know more.

I appreciate, in advance, all the help!
 
I'm actually ordering a VR from New Era (AVR 512 based on this post and they match our pinout). They are about $36 plus shipping. They don't have a US distributor so I emailed them and they will ship direct though it's about $30 for shipping. I can add an extra one to the order if you want to PM me?


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Have you located all ground wires and checked their connections?

As for rebuilding starter and alternator, any good auto electrical shop should be able to do this.
I called around and found a place in Fredericksburg VA. (Just finding an old school shop was the hard part)
I thought I was being smart by buying some stuff like brushes online but the shop tech said he could have found all that stuff quite easily.
For the starter he found some parts via a Toyota forklift parts store.
A shop like that can test your regulator on the bench or in the truck.
 
You might be better off getting a Painless Wiring generic FJ40/ old Bronco kit, it still would be a bit of work to swap all the connections to fit all the switches and relays and what not, you could do a lot of splicing if you get a good water proof type connectors.
 
I'm actually ordering a VR from New Era (AVR 512 based on this post and they match our pinout). They are about $36 plus shipping. They don't have a US distributor so I emailed them and they will ship direct though it's about $30 for shipping. I can add an extra one to the order if you want to PM me?


View attachment 2521044

View attachment 2521618

Am I reading it correctly that it fits the Toyota B Series?
 
Have you located all ground wires and checked their connections?

As for rebuilding starter and alternator, any good auto electrical shop should be able to do this.
I called around and found a place in Fredericksburg VA. (Just finding an old school shop was the hard part)
I thought I was being smart by buying some stuff like brushes online but the shop tech said he could have found all that stuff quite easily.
For the starter he found some parts via a Toyota forklift parts store.
A shop like that can test your regulator on the bench or in the truck.

So, I pulled my alternator and took it to one of those pole-barn, old-school shops out on the edge of a field way out of town. The minute I said "Toyota Diesel, 24v", the guy looked at me and said "son, Toyota never made a diesel." I was gentle, but it took a second to convince him to even touch it at the counter. He agreed to take it when I told him it uses the same brushes as a 1979-1983 Toyota Pickup. He had it about a week.

I picked it up cleaner looking, but he admitted that it took some time pulling it apart because it has a tapered shaft. From there he explained that everything looks good, but he couldn't test it. I asked why and he responded that "I don't have any 24v testing equipment." At that point, I paid him and left rather than explain that a voltmeter would read it. I'm hoping he simply meant he didn't have a stand that could hold it. I'd like to believe the local guy who's been doing it for decades understands the basic concepts.

Is the place in Fredericksburg, VA still around? I would gladly ship to anyone, since I've exhausted my local resources. What did it cost you to have it serviced?
 
You might be better off getting a Painless Wiring generic FJ40/ old Bronco kit, it still would be a bit of work to swap all the connections to fit all the switches and relays and what not, you could do a lot of splicing if you get a good water proof type connectors.

Would the Painless FJ40 wiring be able to handle the 24v system? That's my concern. That's a hefty price to pay to have it burn up. It was one thing to watch my LED brake lights burn out, but would be another to watch that much money melt. :rofl:

Do you have experience with it personally? Is there somewhere I can reference the installation and experience they've had?

I appreciate any and all advice!
 
I just called the folks in Fredericksburg. Yes, you can ship your stuff to them.
I can't remember how much I paid, which means it was probably not too outrageous.

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In general, it is the current or amperage flowing through wires that burns them up. Higher volts mean less amperage. A 24V truck could have thinner wires.
The devices at the other end like a radio need to match the voltage or they will die. LED's are often both 24V and 12V (and 13.7, 21.5 and anything in between) but they have their limits too.
 
In general, it is the current or amperage flowing through wires that burns them up. Higher volts mean less amperage. A 24V truck could have thinner wires.
The devices at the other end like a radio need to match the voltage or they will die. LED's are often both 24V and 12V (and 13.7, 21.5 and anything in between) but they have their limits too.

Thanks for that screenshot of the info. We've already had one guy make a recommendation, hopefully, others reading this will also see this info and explore their options or use one of the two. I'm surprised there's not a member who's made a side gig out of rebuilding some of the 24v parts given that they're starting to come into the US more often.

Also, if I'm understanding you correctly, the 12V harness would work for 24v as it's wiring is larger and can handle the higher amperage?
 
if I'm understanding you correctly, the 12V harness would work for 24v as it's wiring is larger and can handle the higher amperage?
That's almost correct.
Let's say you have a device that uses 120 Watts. In a 12V car that device would need 10 amps of current. In a 24V car, that device would need only 5 amps.
So higher volts means less current (amps).
 
That's almost correct.
Let's say you have a device that uses 120 Watts. In a 12V car that device would need 10 amps of current. In a 24V car, that device would need only 5 amps.
So higher volts means less current (amps).

So, in that theory, 12v harness should handle the 24v system. 🤔
 
Flynn said: "I'm actually ordering a VR from New Era (AVR 512 based on this post and they match our pinout). They are about $36 plus shipping. They don't have a US distributor so I emailed them and they will ship direct though it's about $30 for shipping."
I would like to order such kind of stuff for my BJs, here in Europe, me too. Could you please give me some info how to?
 
Still using the old one, as far as it goes this 37 years old stuff...

PS. Did you, perhaps, register your JDM rig in our 40-Series Registry, so we can see some pics of this rare specimen?
 
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Still using the old one, as far as it goes this 37 years old stuff...

PS. Did you, perhaps, register your JDM rig in our 40-Series Registry, so we can see some pics of this rare specimen?

Not yet. She's in the process of being restored.
 

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