3B Electrical Gremlins (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Dirty Koala

SILVER Star
Joined
Mar 18, 2013
Threads
56
Messages
3,526
Location
Draper, UT
Hey Folks ,
I have an 82 Canada spec BJ42 with a 3B & 24V system. I am having a PIA issue with my batteries going flat after a few days...particularly when running with the headlights and/or heater blower running.

With the regulator disconnected, I am measuring 23.4 volts at idle, and 23.8 volts when idled up to about 2000 rpm.

With the regulator connected (Last time I checked) it was getting about 26V on the high end, which would drop down below 24 when under load.

I haven't been able to find the test procedure for this rig yet, but I believe the voltage should be about 28V which I have never seen.

The prior owner had alternator work done, but I am starting to think this alternator isn't putting out enough juice to keep the batteries maintained.

I will add that I added a fresh matched pair of 850CCA Interstates to rule out a bad battery.

Any ideas? Is there a proper test procedure documented somewhere?

Cheers
 
Its your alt. There is also a draw somewhere in the system to drain them that fast

Or read the post below yours. He found it was a signal light issue in the fuse box.
yeah I just read that...I will check it out. Mine typically only draws down quickly if I am driving with the headlights on.

Would you recommend I try to get the alternator rebuilt? From the research I have been doing it seems that there aren't many options out there for replacement alternators.
 
I have a 24 volt alternator 12/81 BJ42... you'll need to use your own vacuum pump & pulley. I'm switching to 12 volt... no prior problems with it. $50 + shipping
 
I have a 24 volt alternator 12/81 BJ42... you'll need to use your own vacuum pump & pulley. I'm switching to 12 volt... no prior problems with it. $50 + shipping
Done! I'll PM you for payment details.
 
I finally got around to installing the alternator I got from @SuperDuperCruizer and I also picked up a new BJ70 OEM voltage regulator (27700-57080) from @beno as they are still available unlike the the BJ42 version.

Comparing both VR's they are identical with the exception of the plug, so I clipped the round green plug off of one of the old units and soldered all the wires onto the new VR.

20171129_175009.jpg


Looks like someone messed with this VR is the past.
20171129_175658.jpg


Now with a different alternator and a new VR, I am still seeing lower that expected voltage. Without any load and high idle, I am seeing 26.3 volts. lower idle and no load 26.02 volts. When I turn on headlights and fan blower, voltage drops to 24.9 volts.

Next step I think is to start replacing all the ground cables that run to the block, alternator and frame from the battery. They cpukd probably do with a fresh set.

I am open to suggestions and ideas, I am still getting my head wrapped around this 24V business.
 
I agree, those solder joints look sloppy. I just rebuilt an EDIC with a similar round connector. You may be able to remove the rubber plug at the rear of the plastic connector, remove the pins and swapped just the green plastic portion. If I can find my 24 volt regulator, I’ll post what I find.
 
I agree, those solder joints look sloppy. I just rebuilt an EDIC with a similar round connector. You may be able to remove the rubber plug at the rear of the plastic connector, remove the pins and swapped just the green plastic portion. If I can find my 24 volt regulator, I’ll post what I find.

The VR with the sloppy solder was the one that I clipped the round green plug off of and then put it on the new OEM BJ70 VR (first pic). I would have just moved the pins from plug to plug...but the two plugs had vastly different pin styles, so I had to snip and reconnect.

Electrical is such a PIA.
 

Users who are viewing this thread

Back
Top Bottom