Starter Motor (late 1850 LHD) solenoid alternatives

[GinettaG15]

after the "strange" behaviourr of my starter motor today...see above...i disassembeld the solenoid (removal of solenoid cap)

and what i found....the small spade-connector has internaly a small copper-contact which gets powered by 12V, FROM the main contact, once the main-contact of the solenoid closes.

so exactly what i was tinking above with the aftermarket solenoid.

this explains also why the replacement high-torque starters dont come with the 3rd spade connector.

[GinettaG15]

this morning i had some time for investigating.....very interesting result:

i connected a starter motor , laying around from a rover v8, and again: nothing happened, no click, no noise...nothing
i used a 2nd battery with jump-leads , just to exclude that the car´s battey is a weak point : nothing
when my mate sit inside the car and turned the key in start-position i disconnected the white/red wire from the starter and re-connected it straight away --> the rover-starter engaged and was spinning.

now with the white/red wire remaining connected i could repeat the procedue plenty of times....it worked.

i reconnected the original starter and again: nothing
i swapped again to the rover starter: working

than i recognized the following:
once the triumph starter was connected to the battery (thick cable), i had 12V on the bigger spade-connector...it looks like there is a shotcut somewhere internaly the solenoid. this also explains why my battery was always empty after 1 week.

now its up to decide if i invest in a new solenoid or straight away in a high-torque starter motor but i´m confused if the 3rd terminal is present on those high-torque motors?

thsi said...on replacement solenoids for the standard-motor it neither looks present:

https://rimmerbros.com/Item--i-520473

my starter is working again!!

what i did?

i dissassebled the solenoid and seeing the principle and its connections it turned out that it was fitted 180degrees wronlgy positioned to the starter-motor.

how it could ever have worked is a mistery.
i do not own the car for long...when i collected the car it worked, when i donwloaded it from the trailer it worked and it worked 2-3 times in my garage..until it failed, than worked again and than failed permanent.

and now as i have understood the principle i would asume that any aftermarket solenoid without the 3rd spade-connector should work...thats why the replacement one at Rimmers has a spade connector fitted to the big plus-terminal ...the one which connects to the motor side.

and those solenoids can be found from multiple online-stores for around 23,-pound

if this assumption is correct, also the standard solenoid-caps (the ones without the 3rd connector) could be used.