Bendix Ignition Switch

[Super Dave]

We have the "push to start" type of Bendix ignition switch in our 76 F, and just learned that the starting vibrator is not activated until the switch is pushed in. Is our switch bad or incorrectly wired? I thought the starting vibrator should be activated when the switch is turned all the way to the right, even if the switch is not pushed in.

[Alan Fox]

It is wired incorrectly....But if it works , leave it alone...

[ELT]

Be sure your airplane has not been modified to an impulse mag.  You can remove the SOS and install an impulse mag.

[orionflt]

You are correct, you should be able to hear the vibrator buzzing when you turn the key past both but before you push it in. If it is actuating when you push in it is probably mis wired to the starter lug. Another possibility would be the SOS system has failed and your starting when the key is released to the both position (ie: engine doesn't start while cranking but fires when the key is released)

Brian

[Super Dave]

We do still have SOS. So any reason not to leave it as is, as n74795 suggests?

[orionflt]

none at all, I took a lok at one of the wiring schematics for the SOS system and it wires the power to the SOS sytem to the start lug so that you are only actuating the system when you are cranking the eng... now I have to go back and take a closer look at mine, I tink it is wired the same way. I did see a write up talking about a maintenance switch wired under the instrument panel to disable the starter so you can test the SOS system and bypass the starter for hand propping, but that was on B and early C models.

[Super Dave]

Interesting, thanks for the replies all.