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| Centre main bearing with integral thrust washer |
It's raining outside so I don't want to work in the garage as the "lovely Sunbeam" would have to sit in the rain. So I decided to work on the starter motor. It has a cracked plastic terminal cap on the solenoid so thought I would repair it.
Dismantling was easy enough but the removal of the cap was more difficult as the coil wires are soldered in place. I thought the coil would come out with the cap. So managed to snap one of the coil wires. Clumsy oaf.
Repairing the wire is easy enough by crimping on a pin contact. The cap was repaired with some Evo-Stick "serious glue". Whilst inside I cleaned up the main contacts and rotated the moving contacts 180 degrees to balance the wear.
Once reassembled I thought I would test the solenoid. I assumed an earth on the case and a positive on the ignition switch would make it operate. But NO...
A little confused, and assuming I had broken it, I pulled it apart again. 12V across the wires and it works as expected.
Some investigation on the web revealed there are two coils inside. Hence the extra wire.
One coil is used to "hold on" the energised solenoid and is connected from switch input and returns via the body. But this isn't strong enough to pull the coil into place.
The second coil is strong enough to pull the plunger into place but doesn't use the return via the solenoid casing. Instead it returns through the main coil of the starter, then to the casing to the battery. When the solenoid is energised this coil is effectively switched off leaving the hold on coil to do the work.
The solenoid plunger can be tested but you need to apply 12V to the big contact and an earth to the switch (or vice versa).
Reassembly was easy enough, and bench test ran Ok.
The soldered coil contacts are shown as "A" and "B" above.
2 wires on "A" and one on "B" which is connected to the terminal 12V feed to the motor.
Now to do the Alternator....
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