How many amps for ignition?

[Bulldog1]

Good point, regarding little light fingered work shy individuals.
It's always amazes me how much thought goes into stealing other people's prized possessions.

[AdrianC]

The starter solenoid should draw very little current. I've used momentary push-switches before on other cars, with no problem at all. It's probably worth just putting a multimeter across the terminals to see how much is being drawn. A momentary is definitely better than an on-off. Too easy to forget to switch it off again, leaving the motor running.

Actually it's over 30A momentary pull in load and then 11A hold in load.

<boggles> Wow. I'm... amazed. Yes, I can see why relaying it is a good idea... <makes plan>

[Bulldog1]

Would it be ok to fit it with an 'in-line' fuse, rather than a relay as I don't know how to fit it through a relay.

[AdrianC]

Would it be ok to fit it with an 'in-line' fuse, rather than a relay as I don't know how to fit it through a relay.

All a fuse will do is blow if too much power's used. It won't do anything otherwise.

A relay will mean you draw a lot less current through the switch.

Fitting a relay'd be simple.

You've got two terminals on the starter. One's a permanent live, the big fat lead. The other's a thin lead from the switch that's live when you "turn the key".

So...


Terminal 87 goes to that big fat permie live. *Important update* - Don't disconnect that live from the starter, add another wire off the terminal. And be VERY careful - disconnect the battery before you go near it...
Terminal 30 goes to the smaller terminal on the starter.
Terminal 86 goes to the wire which used to be on that smaller terminal.
Terminal 85 goes to an earth.

You turn the key, 86 gets +12v. That earths through 85, closing the relay. That puts a big fat +12v from 87 to 30, and the starter goes whirr.

[bigherb]

I mount the relay like this.

[Bulldog1]

Thank mate,

I'll give it a try.

[kevtherev]

Starter buttons

It'll catch on, I'm already looking where to put it

[Wychall]

The floor mounted button on the early mini's WAS the starter solenoid. The car did not have a pre-engaged starter so the solenoid was remotely mounted. Minors had the same idea with a dash mounted pull switch.
For use with the pre-engaged starter motor, like as what we have, you are just switching the starter solenoid, not the entire starter current.