HJ45 alternator concerns

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hi guys, I saw this thread and I have a followup question. I have a 1975 HJ45 truck with a blown alternator (externally regulated). This is how I got the vehicle. Due to the alternator issue the harness is also burnt some 3-4 wires are melted and I am planning to replace them. The alternator wires are cut off. I have not tested the regulator but I am planning to do that. Could someone advise where from could I obtain a refurbished alternator? @et3surge did you have your issue fixed by replacing the alternator? Is @toyotamatt still around? thanks
 
I think he has checked out. When my OEM alternator dies, I going to do a 100A GM one wire with the proper pulley.
 
Does it supply vacuum to the brake booster or other vacuum switching valves. Maybe an electric vacuum pump could be added to your system.
 
Some photos as I removed. I took it to a local alternator shop and they said they could not bench test it without the vacuum pump attached, is that true? I can’t see what the pump does for the alternator unless it holds the shaft centered. @ToyotaMatt ?
It's true they cannot bench test it (they can put it on the bench with a belt to check it. However, the electronic components can still be tested. They may not feel comfortable troubleshooting something that was taking apart from someone else. Or sometimes people work on it and make it worse so I don't blame the shop for working it. Honestly I has something wrong besides the brush being worn.

Anyhow, does this engine happened to be a H engine or a 2H? What year, sorry I missed it? I have experience with a H engine. I have hunch you have more than one problem.
 
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hi guys, I saw this thread and I have a followup question. I have a 1975 HJ45 truck with a blown alternator (externally regulated). This is how I got the vehicle. Due to the alternator issue the harness is also burnt some 3-4 wires are melted and I am planning to replace them. The alternator wires are cut off. I have not tested the regulator but I am planning to do that. Could someone advise where from could I obtain a refurbished alternator? @et3surge did you have your issue fixed by replacing the alternator? Is @toyotamatt still around? thanks
Cruiserparts.net may a good option. Another one would be cruiserpartss.com. I have never ordered from them. I see an email address in there website, also not sure if they will ship to the USA. You can remove the alternator and take it a good rebuilder. Let them know incase they take the alternator apart, the big o nut the holds it together is reverse thread. I try to go a shop that will work with you. If start your own start your own thread my friend I have more to
say as do others. And sorry I did mean to hijack this thread.
 
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Here's diagram, the accumulator is located under the cab driver side or at least the one I worked on.

1_x_14_Glass_Seal_-_Genuine_Toyota_4 (1).webp
 
Still no luck finding the OEM refurbished alternator with vacuum pump. Has anyone tried using a standard 3 wire alternator with electric vacuum pump? Has anyone done this conversion successfully and if so what were the results?
 
I would do something like this for a 12vdc vac pump. I think a vac reservoir is good addition too. Lots of room in the engine bay for say 1/2 gallon steel can. I like the idea of a demand switch so it doesn't run all the time. I would make the can out of steel pipe 3 or 4 inches in diameter and say a foot long. Big fitting for the hose to booster and a smaller one to the pump.

Amazon.com: FIQAPJ Brake Booster Vacuum Pum Compatible with Cadillac, Chevrolet Swift, Pontiac, Saturn-CTS, STS, Camaro, Caprice, HHR, Solstice, Sky Replaces# 20804130, 20939309, 31317530, UP28 : Automotive - https://www.amazon.com/dp/B0DP8GXNTB $41 vac pump

https://www.amazon.com/Alternator-Output-105Amp-Self-exciting-ADR0151?tag=ihco-20 105 A $65
You might need a different V belt pulley. One of the vendors up top has one that works with the toyota belts. He likely has the 1 wire alternator too. I would monitor the voltage and skip the ammeter.

2 days ago I'm driving to town and my ammeter suddenly shows like -20A. I get to nice place to pull over and investigate. Turns out the battery wire on the alternator had un-clipped. I pushed the connector back on, and ammeter read 0 at idle with the heater on high. Fixed in seconds.

My booster is bad, so I just hemostated the hose closed. I'm a big guy so manual brakes isn't an issue for me.
 
Your original alternator can be repaired. I was able repair mine. I have a diesel engine in the 45. Electronics components in the alternator are not obsolete. I purshased spare alternator and 12v starter since they are almost impossible to locate at a decent price. If you still running everything original with no added loads you should be fine.
 
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I have extra H stuff posted in the diesel classifieds if anyone interested. I switched to 2H. So not using my alternator or regulator but I don’t think those were charging but I didn’t take the time to check.

Jason
Is there any way you could take your alternator and regulator to a local alternator shop to be tested. I would buy both if they are working. thanks
 
I would do something like this for a 12vdc vac pump. I think a vac reservoir is good addition too. Lots of room in the engine bay for say 1/2 gallon steel can. I like the idea of a demand switch so it doesn't run all the time. I would make the can out of steel pipe 3 or 4 inches in diameter and say a foot long. Big fitting for the hose to booster and a smaller one to the pump.

Amazon.com: FIQAPJ Brake Booster Vacuum Pum Compatible with Cadillac, Chevrolet Swift, Pontiac, Saturn-CTS, STS, Camaro, Caprice, HHR, Solstice, Sky Replaces# 20804130, 20939309, 31317530, UP28 : Automotive - https://www.amazon.com/dp/B0DP8GXNTB $41 vac pump

https://www.amazon.com/Alternator-Output-105Amp-Self-exciting-ADR0151?tag=ihco-20 105 A $65
You might need a different V belt pulley. One of the vendors up top has one that works with the toyota belts. He likely has the 1 wire alternator too. I would monitor the voltage and skip the ammeter.

2 days ago I'm driving to town and my ammeter suddenly shows like -20A. I get to nice place to pull over and investigate. Turns out the battery wire on the alternator had un-clipped. I pushed the connector back on, and ammeter read 0 at idle with the heater on high. Fixed in seconds.

My booster is bad, so I just hemostated the hose closed. I'm a big guy so manual brakes isn't an issue for me.
I like the idea of upgrading the alternator to 1 wire 60-80A+ and using the el brake vacuum pump. Why not activate the pump with the stop light switch if amps are not too high. Agree that it shouldn't run all the time.
 
Many ways to skin a cat, none approved by cats themselves.

I don't know the vacuum requirements of your system or the production values of that pump. Having a vac tank should help the overall performance. Electric brake light activation on demand sounds like turbo lag in reverse to me but maybe not. A simple vacuum switch that turns on at say 15 inches of mercury and shuts off at 20 - you could use the brake light with a relay too for additional activation (back up). A 100A alternator should easily provide enough power.

One of my introduction to driving the mountains of Germany in my duece and half diesel that air over hydraulic brakes almost went very bad. I missed a downshift on a steep, narrow and twisty downgrade! I could only get it to go back into 5 th gear (overdrive). It was an adventure much like Wolf Creek Pass but without the chickens. About the time the low air pressure alarm started screaming my friend jumps from the truck (he claimed the door opened and he fell out). I was fully stopped in 20 white knuckled from the ejection. He wasn't hurt, so after he got back in, we proceeded the rest of the way down the mountain with out a downshift.

You don't want to run out of vacuum at the wrong time IMHO.

No Longer Available or prohibality expense means to me field expedient repair. For less than $200 you can have more power and brakes ( parts plus a correct pulley and junk yard mounting bracket you modify to fit) - plus spare units on the shelf for $110.

 
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