Should I upgrade my alternator?
- Thread starter DillonOnTheCoast
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- Thread starter
- #22
When cold I have to give it a bit of throttle to stay at 600 but after 30s or so it holds 600 easily. I looked it up in the FSM and it said 600. I could be talked into turning it up a hair though.
My FSM says 650 for the manual and 750 for the auto
and you are running a few more accessories than Toyota envisioned in the mid 70s during the design phase.I like them idling a little faster,seems to lose a lot of the rattles and squeaks.
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- Thread starter
- #24
setback
I got the rebuilt alternator reinstalled. Now I have a battery light & filter light on.
I haven't put my multimeter on it yet but I have to assume the rebuilders did something wrong and I'm going to have to pull it and give it back to them.
I got the rebuilt alternator reinstalled. Now I have a battery light & filter light on.
I haven't put my multimeter on it yet but I have to assume the rebuilders did something wrong and I'm going to have to pull it and give it back to them.
- Thread starter
- #25
The alternator guys are gonna take another look at it.
In the meantime, I'm seeing 11.8v (battery voltage) at 600rpm and 12.1v at 1500rpm.
This time I'll bring a printout of the FSM breakdown of the alternator.
In the meantime, I'm seeing 11.8v (battery voltage) at 600rpm and 12.1v at 1500rpm.
This time I'll bring a printout of the FSM breakdown of the alternator.
- Thread starter
- #26
Could it get worse?
They said there was something wrong with the stator they chose to use - it fit well enough to pass a bench test but failed when installed on the truck. Who am I to question this?
So another week goes by where they are contacting their suppliers and searching for and ordering parts.
The parts came through and they installed an "80 amp stator", they upgraded the diode to handle higher current and they physically modified the rotor by grinding it. This was necessary to fit with the new stator.
Now it produces current but only at high RPM. They are stymied. They can't put it back to stock either without locating a new rotor. I don't have much confidence in that.
The plan, as it stands, is to combine a delco alternator with the vacuum pump from some other truck. They believe it can be made to fit.
I am dumbfounded. I am also stuck in Sacramento until this is resolved.
More to come.
They said there was something wrong with the stator they chose to use - it fit well enough to pass a bench test but failed when installed on the truck. Who am I to question this?
So another week goes by where they are contacting their suppliers and searching for and ordering parts.
The parts came through and they installed an "80 amp stator", they upgraded the diode to handle higher current and they physically modified the rotor by grinding it. This was necessary to fit with the new stator.
Now it produces current but only at high RPM. They are stymied. They can't put it back to stock either without locating a new rotor. I don't have much confidence in that.
The plan, as it stands, is to combine a delco alternator with the vacuum pump from some other truck. They believe it can be made to fit.
I am dumbfounded. I am also stuck in Sacramento until this is resolved.
More to come.
- Thread starter
- #27
Yes, it can get worse
After the first rebuild failed to perform, they physically modified the rotor, it still failed and were unable to get it back to stock.
They located a 55amp alternator off a different application (had different mounting tab), and put its guts in my alternator case, reinstalled it and it seems to work. Warning lights all went away.
Unfortunately at high idle it wa sputting out over 16v.
They replaced my voltage regulator with an electronic model (I still have my remanufactured mechanical one in case it can be adjusted). Voltage appears normal and I was about to hop in and take it home when the vacuum pump started making an ugly noise.
It is a low but very audible droning / warbling. It doesn't sound like a vacuum leak but it must be because:
What are the possible causes? Bad seal on the o-ring? Broken vane?
Am I just the unlikiest person ever? My vacuum pump & voltage regulator were working fine before I touched the alternator. Ug.
After the first rebuild failed to perform, they physically modified the rotor, it still failed and were unable to get it back to stock.
They located a 55amp alternator off a different application (had different mounting tab), and put its guts in my alternator case, reinstalled it and it seems to work. Warning lights all went away.
Unfortunately at high idle it wa sputting out over 16v.
They replaced my voltage regulator with an electronic model (I still have my remanufactured mechanical one in case it can be adjusted). Voltage appears normal and I was about to hop in and take it home when the vacuum pump started making an ugly noise.
It is a low but very audible droning / warbling. It doesn't sound like a vacuum leak but it must be because:
- Pulled one of the vacuum lines off the cannister and it immediately elimiated the noise. Blocking the hose makes the sound come back. It appears to be pressure-related.
- The noise doesn't change based on engine speed.
What are the possible causes? Bad seal on the o-ring? Broken vane?
Am I just the unlikiest person ever? My vacuum pump & voltage regulator were working fine before I touched the alternator. Ug.
- Thread starter
- #28
Saga Continues
I took care of the vacuum pump but unfortunately the alternator is not charging. I see only battery voltage on the system when the engine is running.
I have also noticed that when I turn the ignition on, before starting, the battery & filter lights don't come on like they used to.
I checked the engine & charge fuses. They looked fine but I replaced them anyway.
I checked all my connections at the batteries & the alternator.
I checked all the battery terminals and they are ok.
The FSM says the voltage regulator is the last item to check. The shop replaced my Toyota regulator with a small black aftermarket unit. It has no manufacturer or part # on it. They also forgot one bolt so it is just sort of flopping against the fender wall.
There is a procedure in the FSM for checking the resistance across various terminals in the regulator. I doubt that procedure holds true for a solid state regulator. Plugged in or unplugged, only the brake light illuminates when I turn on the ignition.
Can anyone shed some light on this? How can I test the regulator I have? As you can imagine, I am eager to bring this situation to a close.
I will either deliver or send a 6-pack* to the mudder that solves this problem.
(* I have no idea how to send beer to Australia but I'll try)
I took care of the vacuum pump but unfortunately the alternator is not charging. I see only battery voltage on the system when the engine is running.
I have also noticed that when I turn the ignition on, before starting, the battery & filter lights don't come on like they used to.
I checked the engine & charge fuses. They looked fine but I replaced them anyway.
I checked all my connections at the batteries & the alternator.
I checked all the battery terminals and they are ok.
The FSM says the voltage regulator is the last item to check. The shop replaced my Toyota regulator with a small black aftermarket unit. It has no manufacturer or part # on it. They also forgot one bolt so it is just sort of flopping against the fender wall.
There is a procedure in the FSM for checking the resistance across various terminals in the regulator. I doubt that procedure holds true for a solid state regulator. Plugged in or unplugged, only the brake light illuminates when I turn on the ignition.
Can anyone shed some light on this? How can I test the regulator I have? As you can imagine, I am eager to bring this situation to a close.
I will either deliver or send a 6-pack* to the mudder that solves this problem.
(* I have no idea how to send beer to Australia but I'll try)
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As I understand it, you had a mechanical external regulator and now a solid state regulator.
When the key is in the "on" postion..... how much Volts do you have on the IGN terminal of the VR and how much on the F terminal of the VR?
Same questions when the engine is running at ± 1500 rpm.
In both situation the output "F" to the ALT should be equal to the input "IGN" of the VR for charging.
Only when the battery is full the output on the F ternimal is less than the input on the IGN terminal.
Do you have a pic of this SS VR? Maybe those "specialists" reversed the IGN and F wires? Or any other combination?
Good luck, Do you ship to Costa Rica? (just kidding).
Rudi
When the key is in the "on" postion..... how much Volts do you have on the IGN terminal of the VR and how much on the F terminal of the VR?
Same questions when the engine is running at ± 1500 rpm.
In both situation the output "F" to the ALT should be equal to the input "IGN" of the VR for charging.
Only when the battery is full the output on the F ternimal is less than the input on the IGN terminal.
Do you have a pic of this SS VR? Maybe those "specialists" reversed the IGN and F wires? Or any other combination?
Good luck, Do you ship to Costa Rica? (just kidding).
Rudi
- Thread starter
- #30
I will do those checks and post back here. As for shipping, no, but I do deliver. Seriously - the whole reason I'm working on this thing is so I can drive it down that way and back.
- Thread starter
- #31
Pics are attached. The unit is actually quite sturdy looking. The back is filled with some kind of rubber so it is completely sealed. There are no labels on the back. The front just says IN555 1587 CN 12V.
Here are the pinouts in my Nov 1985 engine manual, translated to the colors on the aftermarket voltage regulator:
I'll have to wait till morning to do the tests with the engine running.
Here are the pinouts in my Nov 1985 engine manual, translated to the colors on the aftermarket voltage regulator:
- White/Red = Ign
- White/Blue = N
- Green = F
- Black = B
- Yellow = L
- White = E
- Blue = unused
I'll have to wait till morning to do the tests with the engine running.
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- Thread starter
- #32
Ignition Off:
F: 0v
Ign: 0v
Ignition On, engine off:
F: 12.4v
Ign: 12.3v
Ignition On, engine on (1500rpm):
F: 12.4v
Ign: 12.2v
F: 0v
Ign: 0v
Ignition On, engine off:
F: 12.4v
Ign: 12.3v
Ignition On, engine on (1500rpm):
F: 12.4v
Ign: 12.2v
- Thread starter
- #33
I retrieved the old voltage regulator and plugged it in. Still doesn't charge but at least now the battery & filter lights come on when I turn on the ignition. They also stay on once the engine is started.
With the original mechanical regulator plugged in I see:
F: 12.1v
Ign: 12.1v
There is no change from when the engine is started or not.
I guess this is telling me there is no output on my alternator. Why don't the warning lights come on for the solid state VR? Are those lights triggered by some property of the mechanical voltage regulator? Does everyone who replaces the mecahnical regulator lose those warning lights? I just don't know if it is trustworthy.
Anyhow, as soon as the engine cools I'm going to pull the alternator off and have it bench tested. I bet it's dead.
With the original mechanical regulator plugged in I see:
F: 12.1v
Ign: 12.1v
There is no change from when the engine is started or not.
I guess this is telling me there is no output on my alternator. Why don't the warning lights come on for the solid state VR? Are those lights triggered by some property of the mechanical voltage regulator? Does everyone who replaces the mecahnical regulator lose those warning lights? I just don't know if it is trustworthy.
Anyhow, as soon as the engine cools I'm going to pull the alternator off and have it bench tested. I bet it's dead.
These values tells me that the alt is not charging.
This proofs that the alt is not charging.
A little side step:
A. How can the F value be higher then the IGN value?
B. 12.4 Volt is a very high value for a battery who just cranked an engine and is not re-charged. Unless the battery is brand new and fully charged.
I think your DMM is a bit out of spec, but don't worry, if you used an old school analog meter you wouldn't know the difference(s).
Let's wait and see what the result from the bench test are.
Rudi
- Thread starter
- #35
Oh this is rich. The folks at the auto parts store (AutoZone) had a hell of a time getting my alternator rigged up on the bench tester. They have no listings for a 2H engine in their computer so they tore apart a harness to wire it up and chose some random 12v alternator's specs in the computer to test against.
The machine spun the alternator for about 5 seconds before shutting down and displaying FAIL. The B terminal was putting out 29v.
I do believe that the knuckleheads, after destroying the rotor on my 12v alternator, replaced all of my internals with those of a 24v alternator.
When I went to pick it up and put my multimeter on the truck, I saw 15.6v. I believe that was my mechanical VR trying to regulate 24v down to 14v. They swapped it with a solid state VR which held the voltage at 13.8v for about 5 minutes before it died. Since then I've seen ~12.5v regardless of which VR is connected.
Seem like a reasonable explanation?
Next question - what parts are needed to turn it back into 12v? If I were to retrieve my old stator, for example, could I convert it back?
The machine spun the alternator for about 5 seconds before shutting down and displaying FAIL. The B terminal was putting out 29v.
I do believe that the knuckleheads, after destroying the rotor on my 12v alternator, replaced all of my internals with those of a 24v alternator.
When I went to pick it up and put my multimeter on the truck, I saw 15.6v. I believe that was my mechanical VR trying to regulate 24v down to 14v. They swapped it with a solid state VR which held the voltage at 13.8v for about 5 minutes before it died. Since then I've seen ~12.5v regardless of which VR is connected.
Seem like a reasonable explanation?
Next question - what parts are needed to turn it back into 12v? If I were to retrieve my old stator, for example, could I convert it back?
I'm getting confused. 
You say that the alt is not charging, but you read 12.5V which is a sign that there is a little charging going on.
Now the test guy's are telling you that the output is 29Volts?
Is there any load attached to that wire or is it just a meter attached to the B lug?
Hmmmm,
Rudi
You say that the alt is not charging, but you read 12.5V which is a sign that there is a little charging going on.
Now the test guy's are telling you that the output is 29Volts?
Is there any load attached to that wire or is it just a meter attached to the B lug?
Hmmmm,
Rudi
- Thread starter
- #37
The folks at AutoZone hooked it up to a machine with a belt to turn the pulley, a harness plugged into the 3-wire plug on the alt, and a cable to the B term and a ground. I assume this big fancy machine generates load and so forth. I clearly saw 29v on the machine's display.
Why this didn't destroy my batteries is another question. Maybe a bad test?
I've located another alternator rebuilder. As soon as I can get a ride I will take it to them and see if I can get a real diagnosis.
Why this didn't destroy my batteries is another question. Maybe a bad test?
I've located another alternator rebuilder. As soon as I can get a ride I will take it to them and see if I can get a real diagnosis.
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Maybe time to butte the bullet and get a new alternator.
Being a 12v will make it easier.