3B Alternator Alternatives (1 Viewer)

[yotahed]

I'll be doing this on my 3B over the next week. I'll post up some pics. Rufus had it covered pretty good though. Just a mirror image on a 2H. And the mount is ever so slightly different.
My Hitachi NPR 70 amp was around $160shipped +$55 brokerage/duty. Sure beats buying a Toyota unit. However, you gotta hand it to Toyota, 30 year old alternator, and it just quit last week...

...via IH8MUD app

 

[Spore]

How "shot" is the original that you are replacing? There is a place in Medford, Oregon (AA Electric) that I have been taking 3b alts and starters to for years now and they have never turned one away for being too far gone. And that includes one that was seized up and another with bearings so worn that the shaft was, like yours, so loose that you could knock it around. They say they can get all the parts, but all the stuff I have brought to them is 24v, so I am unsure of 12v components. They do a good job and are quite reasonably priced.

 

[yotahed]

There's a fella here in Kelowna, BC that does all kinds as well. He said he'd done a few toyota diesels and I was going to bring mine there........Until I found the Hitachi on ebay and just kinda said 'screw it'
I think my bearings and everything were okay, but I pooched 2 regulators and the diodes are back feeding, and I wanted something pretty.

the new Alt arrived today, I proceeded to removing the pulley because it obviously not going to work. Two skinny grooves.
Ill measure the shaft of both alternators so folks will have a reference in the future.
If theyre different, I'll turn up a sleeve at work for the 3B pulley, and probably wont get to the install untill the weekend.

 

[GV00]

Spore,

Mine is, as far as I know, still working but far enough gone that it isn't worth putting it in with the rebuild. The alternator shop said there wasn't even much reason to test it.

The original I had was a cheapo SA unit as far as I can tell. It failed, and I figured I'd take it apart to do some diagnosis. I quickly realized that replacing the brushes was going to require a pulling it so far apart that I'd basically be able to do a full rebuild, and I really didn't want to have to do that each time I needed to replace the brushes, so I scrapped it altogether.

I'll try looking up AA and see what they say. If it's cheap enough, I may just do that. Thanks for the tip.

Yotahead,

Cool, thanks for another angle on what it is going to take. The increased output is pretty tempting, especially since I'm going to have to do some rewiring to switch to the unit I'm considering rebuilding anyway, so the difference really comes down to total cost and whether or not I think I can fab up a new mount with the same durability as the old.

 

[yotahed]

No worries GV

I measured both shafts today
Toyota is 20mm
Hitachi/NPR is 17mm


I just happened to find a cylinder/threaded plug with an ID of 17mm in one of the spare parts bins at work. Its about 3mm wall with threads on the outside and longer than I need, so its perfect for grabbing in the chuck of the lathe.
Figure I'll only need to turn the threads off for a near perfect fit. Then cut to length and I'm good to go to swap pulleys.

Probably get on that tommorow.
Cheers

...via IH8MUD app

 

[yotahed]

Couple pics of the sleeve I turned up on the lathe. Its a injector preload adjuster off an old common rail of a name I forget...
I can make more if anyone wants to use the stock pulley.

ID is 17mm and it slips on nicely. So the shaft is actually 16.95 mm or so.
OD was turned down to 18.95mm for a snug fit but not a press in. I will cut it to length just shy of the actual stock pulley hole depth so that all the nut torque is on the pulley.
Can't wait to get this thing in.
Cheers

EDIT: I actually measured wrong on the toyota pulley. the shaft OD is actually 20mm. changed in the post above. So i need to turn up another spacer on monday. But im installing the alternator tommorow anyway.

Got the old one removed as well as the mount, and after some CAREFUL measuring this time, I got it down to cutting off roughly a 1/4" off each end of the mount.
The Hitachi shaft is longer and the nut doesnt thread far enough in to engage the toyota pulley. So i took the toyota bearing spacer and put it in between the pulley and lockwasher/nut, and voila. Pulley sits 1/4" forward of stock, allowing me to cut 1/4" off the front and back of the mount for perfect spacing and fit for both alternator ears.
I will need a spacer for the top adjuster arm, but thatll be easy once its mounted..

pics tommorow.

cheers

 

[keving]

There's a fella here in Kelowna, BC that does all kinds as well. He said he'd done a few toyota diesels and I was going to bring mine there........Until I found the Hitachi on ebay and just kinda said 'screw it'
I think my bearings and everything were okay, but I pooched 2 regulators and the diodes are back feeding, and I wanted something pretty.

the new Alt arrived today, I proceeded to removing the pulley because it obviously not going to work. Two skinny grooves.
Ill measure the shaft of both alternators so folks will have a reference in the future.
If theyre different, I'll turn up a sleeve at work for the 3B pulley, and probably wont get to the install untill the weekend.

Do you know the name of the outfit in Kelowna?

Thanks

 

[yotahed]

Ward's Starters and alternators

144 Old Vernon Rd, Kelowna, BC V1X 4R2

(250) 491-4690

My core is good, bearings seem okay and I had good vacuum on the brakes. Just needs a pulley, bearing spacer, diodes and a regulator if anyone needs the parts.

 

[yotahed]

Pics of the modified 3b mount. Ended up trimming 3/16" or just under 8mm off both ends.
Stock length from the front ear to the front of the pulley was 60.75mm.
NPR was 68.08 or something like that.
So that's the measurement I shaved off the front side of the mount. And it just happened to be the same on the rear side.
I used two 1/4" long aluminium spacers to bump the adjuster mount back, allowing a 1/16 for the crush of the spacers.
More pics later on. Its in the truck and wired up. Everything fit up fine except for the vac line needs to be a little longer and I needed to extend the wire harness, as it hooks up on the opposite side.

Cheers

 

[yotahed]

This alternator is sweet. Everything is bright at idle, and doesn't rise much with revs. Gauge sits right in the 3/4 and barely moves. Signals don't make the guage flicker at all.
I noticed right away using the glow plugs after starting the engine don't drag the gauge down and it glows waaay quicker.

I love new s***.

heres a wiring diagram for the NPR/hitachi to an INTERNALLY regulated 3B alt.

Npr diagram is from the rear of the alternator, 3B is from the open end of the green wiring plug.
the wire colors wont matter as long as you pay attention to the positions and label before you cut. My NPR plug was upside down in relation to the diagram, with the keyway at the bottom.

 

[RufusTheDufus]

What did you connect the sense wire to? Straight to the battery or somewhere else?

 

[yotahed]

I'm not sure where they actually go, But all three wires just needed the connector swapped. The LJ 78 stock plug was similar to the NPR one with 3 wires also. So not much hacking had to be done.....


The B+ goes into a fuse box and then over to the battery. Didn't change it.

 

[yotahed]

Couple of pics
You can see the vac pump is considerably larger/deeper than the Toyota. Like twice the size.

Upon warming the truck up, I notice a slight dip in voltage at idle, but comes back to full right off idle. Maybe a 1 volt difference.
My battery was lower than usual and it was charging at 14.9 for a bit, and dropped down to a steady 14.3 at idle.
Pretty happy with the unit so far.
Still have to replace that vacuum hose with something better.

 

[yotahed]

Made up a new spacer yesterday. A slight press fit on the alt. shaft, and a tight fit on the pulley and spacer. Worked out really well. Impacted on and staked the nut.
Sure is hard to get a half mm shaved off a small piece. I went thru a few spacers till I got it right....

 

[mike]

Will this alternator work on a 87 2h mtr?

 

[mike]

Made up a new spacer yesterday. A slight press fit on the alt. shaft, and a tight fit on the pulley and spacer. Worked out really well. Impacted on and staked the nut.
Sure is hard to get a half mm shaved off a small piece. I went thru a few spacers till I got it right....

Will this alternator fit and work on a 87hj60 2h mtr?

 

[RufusTheDufus]

Will this alternator work on a 87 2h mtr?

No.

 

[mike]

No.

Do you know which alternator will work on a 87 2h mtr?

 

[RufusTheDufus]

Sorry. No idea. You might want to try calling your local Toyota dealer.

Of course you'll have to tell them which vehicle the engine is in and if it's 12v or 24v. Then they might be able to help you.

 

[bj40green]

Do you know which alternator will work on a 87 2h mtr?

27020-68100 12V 40Amp
27020-68120 12V 55Amp
27020-68140 12V 80Amp
27020-68150 24V 40Amp
All with Internal Voltage Regulator, still available from Toyota.
Search with toyodiy.com for the correct part# for your Cruiser.

Rudi