MF 150 Starter Wiring

Hello,

I have the MF 150, with a Perkins 152 gas engine and recently had the starter rebuilt. Being an idiot, I didn't take a picture or write down the original wiring, and I thought it would be easy to remember. Well, some were easy to remember!l.

I also have the manual from Yesterday's Tractor, but it doesn't have all the wires that the tractor has on the diagram.

I have these wires (below), and where I think they should go, if you're familiar with the MF 150 wiring of the starter, can you correct where I've got them wrong?

Heavy Red (large hole on metal bolt on metal clip), the Main Starter Terminal.

Heavy Black (large hole on metal bolt on metal clip), Main Starter Terminal.

Light Red (large hole as if it's for the Starter terminal, but doesn't fit the starter terminal). I'm thinking it goes to the "R" terminal on the solenoid? This is the one that's got me stumped.

Light White (may have been yellow at one point, it comes from the Neutral safety switch). Goes to the "S" terminal.

My carburetor "Fuel Shut off solenoid" has a wire that goes to the Starter as well (that one I remember going to the starter). I'm thinking that it goes to the "R" terminal on the starter solenoid.

My understanding of the "R" and "S" on the solenoid is that "R" is for "Run" for when the tractor is Running, and "S" is to Start, and is only "hot" when the key is held in the start position.

Thanks in advance for any help.

Curt

Battery hot wire goes to a large stud on Solenoid.

There should be a charge wire coming from the ammeter to the large stud on solenoid where big battery hot wire connects. Is this your Light Red?

Small S terminal on solenoid should be for ?Start? and come from the starter activation switch via the neutral safety switch. (Your white/yellow wire)

Other small terminal on solenoid should be connected to 12 volts when starter activates. Usually marked I for Ignition but may be R for Resistor. Some models of this vintage had a ?12 Volt External Resistor Required? coil and a resistor between coil and ignition switch. It was actually a 6 volt coil with resistor to match it to 12 volt system. During engine cranking when the solenoid was activated, 12 volts from I or R terminal was connected to coil/resistor junction thus bypassing the resistor and supply 12 volts to the coil giving hotter starting spark.

If it has an electric fuel solenoid I would think that would connect to ignition switch, not starter solenoid.

Thanks for the reply.

The heavy red wire (from battery) as you mentioned is on the main solenoid stud.

There's a larger (heavier gauge) black wire that I've put on the main solenoid stud.

The "lighter red" is a lighter gauge wire. It's eyelet is larger than the eyelets on the wires that go on the "R" and "S" terminal, but too small to slide on the main solenoid stud. I have a new solenoid on the rebuilt starter, and this wire did not slide onto the original solenoid either.

Unfortunately I think I fried something due to the lighter gauge wire being connected to the solenoid "R" side terminal.

The light red wire is hot when the key is on, and is the reason why I didn't connect it to the main solenoid stud.

Something it seems would be simple to find on line, yet I haven't found it yet.

Thanks again for your response.
Curt