How many amps for ignition?

[Bulldog1]

Hello,

Prior to buying my van the electrics were butchered and a toggle switch has been fitted in conjunction with the ignition. The key has to be turned and then the toggle switch activated. A few have burnt out and I can't afford to get it put back to the original spec at the moment.
My question is 'does anyone know how many AMPS draw there will be going through the toggle switch'?
What size amp switch will be safe?

Many thanks

[ghost123uk]

I think the inlet manifold heater will go via the ignition as well but I would guess at somewhere between 3 to 5 amps max. That heater by the way goes off as the engine warms up, so the drain from it is only when cold. If you have (or could borrow) a multimeter that goes up to say 10 amps (though most don't go that high) you could measure it.

When you say you have "burnt a few out" do you mean switches ?
If so, what rating switches are you using ?

You could consider triggering a relay with the toggle switch, that would take all the load off it, and it's wiring.

[Bulldog1]

Thanks for that ghost.

When you say you have "burnt a few out" do you mean switches ?
If so, what rating switches are you using ?

Yes, I've burnt out switches, not vehicles. Thankfully!

The last one that burnt out was a 10 amp, however the van had problems starting and it was on for quite a while.

[bigherb]

Not sure from your description what the switch does is it to switch the ignition on, or to operate the starter motor?
If the switch is to switch on the ignition and is connected into the black output wire of the ignition switch then it works at around 10-15A you really need a 20A switch something like this
http://www.ebay.co.uk/itm/High-Current- ... 20cea13b4b" onclick="window.open(this.href);return false;

[Bulldog1]

Thanks Bigherb,

The toggle switch as suggested simply activates the starter motor. The key turns to activate all lights etc.
Would a momentary switch be more suitable? The starter continues to turn until the toggle is quickly turned off.

[syncroandy]

Surely it would be better to renew the ignition switch ? Its not that hard to do, so long as you've got a 24mm socket for the steering wheel, some means of removing the screw securing the lock housing in place (chisel and hammer).

[Bulldog1]

I changed the ignition switch, thinking it would work. It didn't and the toggle switch is still required!!!!!!

Don't know how to put it back to original as it looks properly butchered.

[bigherb]

Thanks Bigherb,

The toggle switch as suggested simply activates the starter motor. The key turns to activate all lights etc.
Would a momentary switch be more suitable? The starter continues to turn until the toggle is quickly turned off.

Then you need something like this, plenty to chose from on ebay but minimum 20A load

http://www.ebay.co.uk/itm/12V-MOMENTARY ... 4167058ce7" onclick="window.open(this.href);return false;

[Bulldog1]

Thanks Bigherb,

Part ordered.

[kevtherev]

Minis used to have push button on the floor for the starter.
I would have thought that would be an ideal solution
...and very fashionable these days

[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.

[bigherb]

They actually make a good anti theft, suitably mounted they can make it harder to hot wire.

[Bulldog1]

It's a good idea to mount it where it's not obvious what it is! I'll post photos once it arrives.
Many thanks for your replies.

[bigherb]

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. The worst part is the 300-400v release voltage spike arcing across the switch terminals. One reason it is a good idea the fit a starter relay or a dump diode in the circuit.

[bigherb]

I'll post photos once it arrives.
.

Best not.
Lets let the more light fingered Herberts guess.