Should I upgrade my alternator?

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I did some Googling and found these web sites;
http://seekpart24.com/teamec/alternator-212422?c=100350&at=3303
It looks that this one is complete with the vac. pump.

http://www.autoelectricsdirect.com.au/index.php?_a=product&product_id=104

http://www.nationaltruckspares.com.au/Parts.aspx?ProductTypeID=5&BrandID=9&SearchItem=&b=1

http://www.autopartswarehouse.com/replacement_sm/toyota~alternator~replacement.html

Maybe you can find one here.

You can also look for the brand name BERU which is a sub brand from BOSCH. Or Google for Nippon Denso.

Do you have the Toyota part# and the Nippon Denso part# for me? I want to check something out.

Rudi
 
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I don't have a part # - my PDF service manual shows a different unit for 1984. I believe I have the 1979-1983 version.

The key is making sure it fits my bracket and works with my vacuum pump (or comes with one).

Right now my alternator is at a new shop. I should know something tomorrow.
 
New shop called this morning and said he had a theory but needed to see my old rectifier and stator to be certain.

I retrieved the parts and sure enough, he immediately saw what he was looking for. I didn't quite follow but from what I gather, my FrankenAlternator has an unnecessary triple diode and it has also been built in such a way that it will only work with A circuit voltage regulators (like Ford uses) as opposed to B circuit regulators like Toyota uses. He also found and fixed some other issues (broken brush holder, etc).

For reasons I don't fully understand, it is easier for them to adapt my wiring harness to connect a Ford-style 4-wire regulator to my vehicle than it is to get my FrankenAlternator to be compatible with Toyota regulators again.

Does that jive? I can't quite wrap my head around it.
 
Hi Dillon,

I'll try to explain what happened. Your alternator is in fact a 3 phase generator with build in rectifier diodes. To get DC output there is a rectifier plate with 6 diodes. If one (or more) of those 6 is kaput you have a low voltage output.
A good technician will replace the complete rectifier plate because when one is broken the other 5 have had a blow and are prone to follow. So if you replace only the broken one you are in for a series of future repairs. What your previous "tech" did is bridging the broken ones by soldering new ones on top of them.
On top of that he damaged the brush holder and other things.
Now here comes the solution: try to find that rectifier plate!
It's no longer available by Toyota. Try to find 6 new diodes. The ones used by some "repair shops" are not up to spec and don't hold long. So what your new tech is going to do is rewire the alt and connect the 3 phases to an A regulator which has the rectifier diodes build in. Or he can keep the original VR and use a separate rectifier unit, but that is up to him.
I had the same problem and the easy way out for me was to install a rectifier plate from a Caterpillar shovel which my tech had in a corner of his workshop. See pic below. You can see the 3 wires from the alt (which are AC) and on the right you see the white/blue stripe wire which is the +B output.
DSC06343text.webp

Hope this helps a bit.

Rudi
DSC06343text.webp
 
I got the alternator back from the new shop. Those guys gave me a lot of confidence but ... it still doesn't work. The warning lights are on the dash and I am seeing battery voltage only - no output from the alternator.

bj40green:
That does help - thank you! I don't fully understand how the alternator functions ( I have a "how stuff works" level understanding) but what you say makes sense.

I believe I have two rectifier plates from my original alternator. I have no idea what the rectifier plates look like in my new FrankenAlternator (a combination of a 55amp toyota alternator and my initial 40amp alternator).

I have attached a couple photos from my alternator parts box.
P1130117.webp
P1130118.webp
P1130119.webp
 
Here is a scan from the receipt. I asked them to give me a detailed breakdown of what they had to "fix". This is what they said they did.

What do you guys think of the 2amp vs 4amp draw issue on my old vs new rotors?

I can't get back over there until Monday. i need to make some progress so I can get on the road soon or I'm going to lose my mind. ug.
lehr-alternator-round1.webp
 
So, if the alt & 4-wire VR test out ok on the bench then why don't I get any output from the alternator when it is installed? Why do all the warning lights come on the dash?

The manual calls for:
  • drive belt - ok
  • battery cables - ok
  • engine fuse - ok
  • ignition main relay - I haven't checked this. I'll look
  • fusible link - where would I look?
  • alternator regulator - ok
  • alternator - ok
  • wiring faulty - which wiring should I look at?

Everything was fine before I let anyone touch it.
 
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Have you checked the ground cable to the block,Im not sure if I have already mentioned it.
Ive seen them corrode badly and go green
Fusible links are usually near the + battery terminal
 
Grounds are good and I see no fusible links visible.

I'm told I should find nothing on the F terminal, ~7.5v on the stator ("enables" the VR to turn on), battery voltage on A and a good ground for the case.

I started unwrapping wiring to do these checks and I found this. I'm not sure whose handiwork it is.

I wonder if that means my Toyota mechanical VR works with a 4amp rotor and it was just the solid state one that couldn't handle it. My Toyota VR behaved the same way as the Ford one I'm using now.

In other news, he also showed me where my original stator had a damaged diode from when the first shop tried to weld it. I can add that to the list of things they screwed up. Who knows which parts those guys actually broke.

If anybody in the Sacramento area needs alternator work done, I can highly recommend the new shop but until my dispute is over with the first shop I don't want to name names. PM me if you need work done.
20120516-Landcruiesr-LX3-01-brokenharness.webp
 
So here is your problem; No Field!
White / black is ground
White / green is field
White / blue is V output.

No field = no V output.
 
Ground(s)

The battery Neg is connected to the engine.
The Alt is internal grounded en mounted on the engine.
So this is the main return path for the Alt.

From the engine goes a wire strip to the frame/chassis. The body is mounted on the frame with a bunch of nuts and bolts.
All the electrical stuff is basically grounded to the body and / or frame.
The VR is mounted to the body with his housing/internal ground.
In theory there is a possibility that the ground from the body is not equal to the ground of the engine so Toyota runs an extra ground wire from the VR (housing) to the Alternator body.
In theory that wire is not necessary, but they designed it that way. It's up to you to leave it as is or to bring it back to stock.

Rudi
 
Success ... finally. The wiring is a bit of a hack since I don't have a real plug and just used some bare female disconnects to attach to the alternator.

However - it works! Warning lights go off and the batteries are getting a charge.

I can't say whether it is better than before I started this fiasco but at this point I'm just glad to be up and running again.

Now to find a Toyota alternator plug ...

Thanks all for your assistance.
 
Hydro boost brakes, twin stick that transfer case, single wire 100amp alternator. and you're set. If twin stick is too much money/work. use a ford aux. vacuum for 4x4. no problems, Ebayable for under 300.00
 
Vooodoobillyman which single wire 100 amp alt did you use .. ?

Bolt on .. ( on 2H bracket ? )

I'm already on hydrobooster ( got sick of vacuum issues )
 
Did a 12HT swap into a 12 volt cruiser, And changed the 12ht to 12 volt. Ended up fabbing a bracket and going with a GM alternator. I see them on eBay for around 100.00 most of the time. the tab to tab is wider on the gm, long bolt and a some galvanized pipe cut to move the alt forward or back to align the pulley. and bend the adjustment hanger with two right angles to match the depth of the top tab in relation to the pulley position. easy mod. the aux vacuum pump can be sourced from a VW,Mercedes, Audi or an early ford, a electric one that you can remote mount, for the transfer if you are using Toyota.
Spacing for the alt is not a problem because the alt/vac assembly is bigger than the gm, You might have to make a plate and weld two tabs on it if the diameter is two large on the gm for the space, I don't know the limitations on the engine you have for space.
The cruiser had a dual battery setup parallel for the accessories no problems with that charging system. And you know how nice hydro boost is. night and day. with big tires it a must. good luck
 
bj40green said:
Good job! :bounce::clap::bounce2:
Rudi
Click to expand...

Not so fast :( After a couple weeks of trouble-free driving, the warning lights on the dash have started pulsing.

It never happens during the first few minutes of driving and it seems more likely to happen after idling down from a highway run.

Once it starts, it will pulse a bit faster than 1/second. It stops immediately if I put some load on the system (headlights or blower motor).

Voltage regulator? If I'm going to start chewing those up regularly I will be unhappy.
 
Time for the Voltmeter. Check voltage on the battery at idle and at higher rpm's. Do the same with the headlights on and see what readings you get.

Rudi
 
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