MF 150 Wiring Questions: Resistor and Solenoid

[offset1968]

(originally posted in wrong forum)

Hello Everyone,

I've posted a few times regarding an old MF 150 my Dad and I have been running for the past year.
Overall it has been doing really well, especially in L1, only thing is you can walk faster than that 1st Low Gear

Some recent issues: Solenoid suddenly seemed to fail ... and having replaced ... seems to have happened again.
The first one that failed was OLD, I don't know if original, but it was OLD.

The wiring had already been entirely replaced when we purchased, we have replaced a few lines but in general it is wired in as simple a manner as possible.

We have one of those Amazon 'copied' factory manual that we purchased but the graphics are so poor the wiring diagram is useless. Plus again this one has nothing wired other than the motor .. no lights, no gauges, no safety switches.

First question: From the resistor block, we feed the coil a lower voltage as I understand to not burn up the points, but why then do we feed the coil directly from the "R" on the solenoid?

Won't this be a high voltage that would in fact burn the points?
Should "R" be fed into the other side of the resistor instead of directly to the coil since in this case I have the older points distributor?

Next question would be if this wiring diagram is correct ... or can this wiring be leading to this sudden issue of multiple solenoids suddenly dying?

This is exactly how our tractor is wired .. quick diagram I made:

 

[Jim.ME]

(quoted from post at 21:44:55 11/29/20) (originally posted in wrong forum)

Hello Everyone,

I've posted a few times regarding an old MF 150 my Dad and I have been running for the past year.
Overall it has been doing really well, especially in L1, only thing is you can walk faster than that 1st Low Gear

Some recent issues: Solenoid suddenly seemed to fail ... and having replaced ... seems to have happened again.
The first one that failed was OLD, I don't know if original, but it was OLD.

The wiring had already been entirely replaced when we purchased, we have replaced a few lines but in general it is wired in as simple a manner as possible.

We have one of those Amazon 'copied' factory manual that we purchased but the graphics are so poor the wiring diagram is useless. Plus again this one has nothing wired other than the motor .. no lights, no gauges, no safety switches.

First question: From the resistor block, we feed the coil a lower voltage as I understand to not burn up the points, but why then do we feed the coil directly from the "R" on the solenoid?

Won't this be a high voltage that would in fact burn the points?
Should "R" be fed into the other side of the resistor instead of directly to the coil since in this case I have the older points distributor?

Next question would be if this wiring diagram is correct ... or can this wiring be leading to this sudden issue of multiple solenoids suddenly dying?

This is exactly how our tractor is wired .. quick diagram I made:

Did you review the answers you got to your post on the Harry Ferguson Forum?

 

[offset1968]

Update:

It took me a few weeks to get out again, weather was not the best either.

Starter motor completely melted ... all wiring.
I do not understand .... shop says it was either over start abuse .. which in our case would not be true or shop said it could have been a bad battery.
I believe in the other thread I noted that the battery was suspect but I have a hard time believing that a bad battery would melt all internal windings of the starter motor.

 

[offset1968]

Final Update:

As noted, the started was ruined and to be exact the armature seemed to have exploded, pieces of wire falling out of the case.

Yes, it was the battery. A battery that did always read above 12v but a battery as I noted in the other thread would always fail when put on a charger.

The shop noted they thought we had tried to jump start the tractor with an arc welder..... then it all made sense to me.

Low voltage ( poor battery ) ... with high amps ... result is one blown up armature and a need to rebuild the start a 2nd time.

I finally put a barrowed load tester on the same battery in question and yes again sure enough ... battery voltage would drop below 6 volts with load.
Lesson learned.