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Electric reverse wiring and switch?
colimp66 - 11/1/22 at 09:39 AM

Hi,
I am at the point of fitting the electric revers to my imp using a gear in the propshaft/diff area with a Kia starter motor.

What style of switch has been used for this purpose, toggle or push fit and what should the amp rating be for it please?

Any advice will be appreciated.
Cheers
Col.

Sanzomat - 11/1/22 at 09:50 AM

Can't claim to be an expert but I did look into this for my BEC Locost. Whatever switch you use it needs to operate a high current relay for the actual power to the starter motor as it'll pull quite a bit of current. Also, you should wire it so it only works when the neutral light is on (or I guess an interlock switch from the clutch) as apparently turning bike engines backwards can lead to serious internal damage. Also needs to be a switch that you have to hold on so stops as soon as you let go.

In the end I didn't bother and just get out and push!

colimp66 - 11/1/22 at 10:05 AM

Thank you,
I'm not an expert either and electrics aren't my favourite thing to be doing to be honest but would like to get it right so the thing doesn't go up in flames. ;-)
I was looking at a push button starter button with a 50amp loading capacity which I thought would be ok for it. The neutral light connection is a good idea, thanks, best to be safe in that respect.

Cheers
Col.

40inches - 11/1/22 at 10:20 AM

I used a small joy stick type control and safety switch to stop accidental activation, played it safe with a 50amp fused/relay.
But a starter button should work just as well
Reverse Switch Panel
Reverse Switch Panel

gremlin1234 - 11/1/22 at 10:30 AM

I suggest you avoid having the high current cables running to the dash and back.
you would be much better off using low current cabling and switches, and a relay close to where it would be needed.
this cuts down on the length of the high current cable, and also means all the stuff behind the dash can be suitably fused.

the type of relay I would use is below.
https://rimmerbros.com/Item--i-134174

Sanzomat - 11/1/22 at 11:19 AM

quote:
Originally posted by gremlin1234
I suggest you avoid having the high current cables running to the dash and back.
you would be much better off using low current cabling and switches, and a relay close to where it would be needed.
this cuts down on the length of the high current cable, and also means all the stuff behind the dash can be suitably fused.

the type of relay I would use is below.
https://rimmerbros.com/Item--i-134174


Absolutely. Also, if using the neutral light to prevent turning the engine backwards, the switch that runs that circuit is very low current rated so would have to be part of a logic circuit with the reverse switch to feed the relay coil. Fairly simple - take power piggy backed off neutral light via the reverse switch to the relay coil - only energises the coil when both in neutral AND reverse switch operated. Relay switches the high current wiring to the motor. No need for high power rated switch, just a chunky relay

CosKev3 - 12/1/22 at 10:14 AM

If you don't need to IVA the car don't bother wasting your time with a starter motor reverse!

They are only any good for moving a BEC backwards to pass the IVA,in the real world you will find it won't move the car on anything more than a flat surface.

Over the years I had a BEC both times I needed a reverse gear meeting big tractors on narrow roads the starter motor reverse would not move the car as I needed to reverse up hill.

colimp66 - 22/1/22 at 04:53 PM

gremlin1234,
Thanks for the tip off with that relay. I now have it fitted to the framework and it works a treat with a rough bit of wiring being trialled before it all gets fitted back into the car.

CosKev3,
I understand what you are saying about the starter not being great for reversing up a hill, I'm hoping I will never need it for that. I only want it there just in case its needed in a car park or flat surface area if I get caught out with parking, might save the embarrassment of getting out and pushing.