Aux starter solenoid mysteries

[DREDnot]

Making progress on my M1078(A0) Frankenharness.
Got power flowing. Warning buzzer fully functional....
Master power gets fuel solenoid to clunk. Trans control powers up with N-N showing. Pressing start switch clicks the relay but no crank.

a couple months ago I Jumped the starter and it cranked and ran on ether so Im pretty sure the starter is OK.

Im trying to figure out the proper function of the AUX solenoid...



It seems like its purpose is to serve power to the TL26 lug of the starter and signal STE/ICE about it.
The starter relay should send 24V to the TL33 lug to energize the solenoid and send power from the TL9 lug to the TL24 lug that takes power to the TL26 lug to engage the starter....correct?

And these mystery wires...



Im pretty sure these are the leftovers from the P81 thermal cutout from the early starters.
This starter doesn't have the thermal switch.
Do these need to be connected to provide a ground for the AUX solenoid to allow a start?

 

[Ronmar]

Yes, that is how it works. If those wires were for the thermal switch then yes, they need to be connected to each other to complete the circuit for the aux start solenoid. The individual wire numbers should be 93 and 93A on the thermal switch wires, and I can actually see “93A” on one of the wires in your pics...

 

[DREDnot]

Thanks for the confirmation.

This may be a clue as to why this thing was originally sidelined at FMS

The patina on the wires make me think its been like this for a while.



Maybe it was wire nutted...poorly...definitely wasn't twisted together

 

[DREDnot]

Next time I can get out to the truck,
(106* in the shade)


Im gonna De spooge the AUX solenoid terminals and check for power and function.



Reconnect the 93/93A wires and make the connection solid.
Then try to crank it up...

 

[Ronmar]

Next time I can get out to the truck,
(106* in the shade)

Yea, but its a dry heat...

 

[DREDnot]

Success...
It was 95 degrees with some rain today so a perfect time to give this thing a go.
Trimmed off the corroded wire and threw on a crimp connector.



Fired right up.
My guess(hope) is still that this may be the problem that got this steel soldier booted from the army.
Half assed wire nut bypass job came loose and no more start? Who knows?

If I get ambitious, I may add a switch there to act as a starter disabler.