SkyTec starter solenoid question

[Flyguysr5]

Since they seem to be problematic why not bridge across the main terminals and take them out of the system? I have a firewall mounted momentary starter solenoid in the system now. Why have 2 locations for power loss? What am I missing?

 

[Chipper G]

Sky tech told me to not use their Solenoid and to make sure I used one in the system. It doesn’t make sense to me because you still use there’s but that’s the deal

 

[Cth6]

Depends

I believe some of the skytec starter solenoids actuate the pinion like the 149-12LS. Bypassing that would render your starter useless.

 

[hgerhardt]

All starters with on-board solenoids that I know of use them to engage the pinion gear to the ring gear, so without the solenoid, the starter cannot crank the engine.

The other function of most starter-mounted solenoids is to be an electrical contactor, which most airplanes do not take advantage of as they still employ firewall-mounted start solenoid/contactors.

Every one of the several Skytec solenoids I've had fail were from the plunger becoming sticky, or galling, so that it no longer slid into its housing easily. My opinion is the stickiness is due to dust and debris being slung into the starter nose and then migrating onto the solenoid shaft. Cars don't have that issue as they have a dust shield to keep the flywheel area clean.