MF 135 starter wiring

[Tracy]

I have a 1966 MF 135. All was well until I had starter rebuilt with a new solenoid on it. tractor cranks good,but alternator(or volt.reg.)doesn't work now. Any suggestions or a wiring diagram would be helpful. Wiring as of now: Large A+ battery lead and fairly large(about 10#) black wire to contact terminal.(this wire seems to go to ammeter)
12V from start switch to small solenoid term. nearest engine. A red wire to remaining small terminal.This wire goes to parts unknown!

 

[Soundguy]

On most of the old tractor electrical systems.. ( like ford/fergusons ).. the ignition and charging systems were for all intents and purposes.. seperate.

Now.. do you have an oem generator.. or has it had an alternator conversion?

If an alternator.. is it hooked up correctly to the voltage regulator? If you are unsure.. take the alternator into a repair shop.. ( not parts store... go to a real starter/generator/alternator repair store ).. though unlikely.. it is possible that the alternator or reg decided to 'die' during your starter repair.. unless you hooked up something wrong and cooked it.

Provide some more info.. Is tractor starting and running fine.. other than no charge?

Soundguy

 

[Tracy]

Tractor has alternator and since it is a diesel it has no ignition system. It cranks and runs fine except no charging voltage to battery.No alternator wiring has been changed nor has any regulator wiring been changed. Only question is wiring to starter solenoid.I wonder what red wire to small terminal,not the one to starter switch, is for?I wonder if it served some purpose that new solenoid is not wired to handle??

 

[LLove]

We have a 1974 MF 135 at work, also a diesel. On it, the electrical system feeds thru a Oil Pressure
switch. This is from the factory, to "Turn off" the charging system. When you Kill the engine, the Oil
pressure falls to Zero, the pressure switch opens = turning off the Charging system like a Ignition Key
would on a Gasoline Engine.
The Manuals are at work, I'll bring them home Monday night.
What brand of Alternator does your tractor have? They came with different brands, would help to
know in case you're problem turns out to be more complicated than we wish for.
Lloyd

 

[Tracy]

Llove,
Tractor has a Delco Remy alternator. I think the oil pressure switch is probably the answer. I took red wire loose from starter solenoid terminal and touched it to 12volts and alternator started charging battery. Problem was regulator relay remained closed with tractor not running.This would discharge battery,and probably damage relay.
Considered putting manual spst switch in line,but would rather do it correctly.

 

[LLove]

Charging is GOOD! At least you know the alternator works. If the tractor didn't come with an Alternator
from the Factory, it probably doesn't have the "Ammeter pressure switch". Lift the hood and look at the
bottom of the Oil press guage. If it's there,or if you want to add one in,it is screwed into a 1/4" Tee that
has the pipe threads to match= Oil press guage, Oil press line, and the Press switch. All 1/4' npt.
The Press switch is available at auto parts, tractor dealers, you get the Idea. Rated for 5psi.
If you go the SPST switch route, it would also work. Same idea but with a small difference. You have to
remember to turn off the Switch, going with a pressure switch makes it automatic.
If the Voltage Regulator has 3 electrical terminals it's for a Generator. 4 terminals means it's for a AC
Generator= Alternator. If you have a Delco unit with a Internal Regulator, you don't have to use the
External Regulator for the charge function.
Both the Gasoline and Diesel versions show the same Solenoid, However I know from personal experience
that the Solenoid is not the same as a standard Delco unit found on cars and trucks. It's marked the same,
"S" - "R" terminals, looks the same, but internally it is Electrically different. The "R" term remains hot after
you release the Starter Switch, unlike the Auto version which is only hot while cranking. Had to get it from
the tractor dealer, the AC DELCO supplier couldn't. The Red wire probably goes to the "R" terminal at
the starter.
You'll get it working,I'am sure. Lloyd