SG Question

[Dajeepman]

I know the F terminal dictates the output of the SG.. i know if you ground it out it goes to full charge. So when i first start my Cub 108 the Ammeter bounces around alot but once i runs a min it goes full charge... pegs the Ameter to the right.. It starting to boil my battery. All wires check out good. New wireing harness. 2 different VR and they both do the same thing. so Either the SG is shorted internally. or I got 2 bad VR. Is there a way to test the SG to make sure its not shorted internally?

 

[mgonitzke]

Delco Service Bulletin for Starter/Generators has the following info:

 

[Dajeepman]

Delco Service Bulletin for Starter/Generators has the following info:

View attachment 157544

If i remove the F wire... all charging stops.

 

[mgonitzke]

Are you sure you are connecting the regulators correctly? The terminals must match the correct wires, and the terminals will not necessarily be in the same physical location on every regulator. For example, a lot of the newer ones have the "GEN" terminal on the back.

 

[Dajeepman]

Are you sure you are connecting the regulators correctly? The terminals must match the correct wires, and the terminals will not necessarily be in the same physical location on every regulator. For example, a lot of the newer ones have the "GEN" terminal on the back.

I tried everything.. I thinking on mounding a 1 wire mini alternator to the size. be done with the VR all together , I can't keep buying VR.. im on my 3rd and all over charge like constant 20amps.

 

[lpalma]

You can also disconnect the amp gauge and use a junction block to isolate it. Then you can check if it is the issue by using a meter to check the voltage at the battery.

 

[Dajeepman]

You can also disconnect the amp gauge and use a junction block to isolate it. Then you can check if it is the issue by using a meter to check the voltage at the battery.

I put a clamp amp meter at the SG and when I first started it up I get around 2 to 4 amps charging... then not even 45sec of run time it goes to 18 - 22amps and stays there. It's a fresh battery.. it can't take that kind of charge so it boils the acid.

 

[lpalma]

I put a clamp amp meter at the SG and when I first started it up I get around 2 to 4 amps charging... then not even 45sec of run time it goes to 18 - 22amps and stays there. It's a fresh battery.. it can't take that kind of charge so it boils the acid.

So the one on the Dash is disconnected?

 

[Dajeepman]

So the one on the Dash is disconnected?

No it's still connected, it's pegged to the right when running

 

[dsarow]

Do you have a shop where you could take the SG ?Seems like you have tried just about everything!

 

[Dajeepman]

Do you have a shop where you could take the SG ?Seems like you have tried just about everything!

I think there is on in Dallas that can work on them. I might have to take it there to bench test it.

 

[mgonitzke]

Did you go through the rest of the procedure I posted for troubleshooting excessive output? Being that you remove the wire from the "F" terminal and charging stops, it probably isn't the starter/generator itself.

I doubt you ended up up buying 3 bad new regulators- if this keeps happening you are connecting them wrong, or there is some other fault in the wiring harness. I'll ask again, have you verified each wire is connected to the properly labeled terminal on the regulator, keeping in mind the "GEN" terminal may be on the back, and there may not be a ground terminal for the ground wire used by this series of tractor to connect to since most/all of the new ones I have seen ground through the mounting tabs.