Hi all, I have done some research on how these starters work and thought I would share my findings.

So you have a starter motor with a solenoid on top of it to engage the starter drive to the flywheel ever wondered how it works, try this, sorry if its hard to follow but give it a try.

Click image for larger version. 

Name:	20180218_160916.jpg 
Views:	1 
Size:	139.9 KB 
ID:	70741

On the solenoid there are 2 small connections "A" and "B" below these are 2 big connections "F" and "G".

Click image for larger version. 

Name:	20180224_121148 A.jpg 
Views:	1 
Size:	123.2 KB 
ID:	70742

Connections A and B are only connected to the relay inside the cover of the solenoid and go nowhere else.

"A" connects to the Armature (rotor) of the Generator.
"B" connects to the starter button.
"C" connects relay contacts to ends of coil1 and coil 2.
"D" ground for coil 1.
"E" connects to "G".
"F" connects to the Battery.
"G" connects to the starter motor by large copper strip (not shown).

So inside cover you see the relay at the top of the pic and on the side of this a screw connection "C" this connection has 2 ends of 2 separate coils, (coil 1 "C" to "D") (coil 2 "C" to "E") in the main solenoid.

Click image for larger version. 

Name:	20180224_120910 A.jpg 
Views:	1 
Size:	99.2 KB 
ID:	70743

Click image for larger version. 

Name:	20180224_120849 A.jpg 
Views:	1 
Size:	109.2 KB 
ID:	70744

when the starter button is pressed the relay is energized by "A" and "B" and a connection is made from "F" to "C" this powers the coil 1 "C" to "D" and powers coil 2 "C" to "E+G", because the starter motor is not turning at this point "G" is grounded through the armature of the starter motor, so both coils are powered and this pulls the rod into the solenoid and engages the drive gear with the flywheel also connecting "F" to "G" and powering the starter motor so it turns. Now because connection "G" is powered coil 2 has the same voltage both sides of it so it does not work or pull a high load, as the starter gear is already engaged and the motor is cranking the engine, the solenoid is only using coil 1 to hold it in position, once engine has started and starter button released this cuts the power to "C" and the coil 1 is de-energized so releasing the drive gear from the flywheel and stopping starter motor turning.

Now the engine is running all is good, but what happens if you push the clutch pedal down too far and it presses the starter button ? Answer nothing, this is because now the generator is producing power and connection "A" is no longer grounded through the generator the relay will not work to energize the starter !!!