Starter Motor wiring

[Guest jeffhampton]

I have a 1951 Desoto Custom Coupe. It was missing the starter and I purchased a 1950 starter, thinking it should work. The solenoid is different and has an extra lug. Can anyone tell me if these starters are interchangable and how I can wire in the new starter solenoid?

[Rusty_OToole]

My DeSoto repair manual shows the 1949-50 as using a MCH-6102 starter and the 51-52 as using an MCH-6109.

The difference is the earlier model used a starter relay, the later one is actuated directly by the key switch.

Is there any chance of getting the correct starter? Or even the correct solenoid, they should interchange.

The early starter, with the square relay and 4 wires, was connected as follows.

Big lugs:

Battery , ammeter, horn relay all on one lug. Also convertible top pump.

Automatic choke

Small lugs:

Voltage regulator (ground)

Start position of key switch

The newer starter had the following connections

Battery, horn relay B terminal (green), turn signal light,convertible top switch

Start position of key switch (brown)

It should be possible to connect up the starter as if it was the newer model and simply ignore the unused lug choke lug if you don't need it. The ground can be grounded anywhere, it does not have to go to the voltage regulator, that was just a convenient place for it.

Hope this helps.

[Guest jeffhampton]

Thanks! I will try hooking it up this week.

[Guest jeffhampton]

This did indeed work! Thank you very much Rusty. I am still looking for an original starter, but this will do in the mean time. Again, thank you for your time.

[Rusty_OToole]

Glad it worked for you. I value such feedback as it helps fine tune the answers.