Ignition starter button
 

On my 68, I have 2 system starting ignition. The one in which you turn the key and press a buton. Does anyone know what colour wires should be coming from the back of the starter button. The wire going in from the harness is yellow. Should the one coming from the ignition switch also be yellow. The push button doesn't seem to show on the wiring diagram.

thank you for your help

The button ought not be there.

"insert key, push key gently while turning to right (clockwise),
listen for engine spitting, coughing, backfiring, then starting. Release key, e-brake, (hopefully) drive away."

someone added the button.... not stock

a 356/912 switch can replaced the one you have.

This is the back of the ignition/starter switch:


http://forums.pelicanparts.com/uploa...1472921060.jpg


The yellow wire goes to the starter. If your starter doesn't turn over check to see if the yellow wire is disconnected at the starter. Also the black wire at the starter goes directly to the battery.

The red one at 50 goes to the #1 fuse at the fuse block. The two red at #30 goes to the to the #30 at the headlight switch and the the #30 at the combo turn/wiper switch. The one at 57a goes to the 57a on the turn/wiper switch, and the red/white at 75 to the radio.

If the switch is aftermarket for a generic car, or just a bad switch. Then it should be replaced with a proper switch. A 356C switch is actually the same as a 912.

Andrew

The contacts in the switch, used to power the starter have a very hard life and often burn, specifically when the starter relay/motor combination is getting old and has a poor maintenance history. The starter relay takes relatively much current when activated, but even more important, it causes high voltage peaks when released. These peaks burn the starter switch contacts, in the end resulting in a switch contact failure. I think this happened and the previous owner was too lazy to do a proper repair and replaced the starter contacts by a cheap separate switch.

So, if you replace the ignition switch, I would advice to check, clean and rebuild the starter motor/relay. If you want to do an even better job, use an additional smaller relay to power the starter relay reducing the current through the ignition/starter switch, which also results in a better function of the start motor wit a hot engine. This might be a subject for later. Put it on the to-do-list. I only want to say that all failures have cause that must be eliminated, unless you would like to have the same problem again ...

Otto

Thanks for that information. The ignition switch is worn out and I was going to replace it. If I replace the ignition switch, am I understanding correctly that I would no longer need the button? I had thought that it was original to the car, but clearly not!

Thanks for the advice.

The wiring to the starter, after about 50 years, may require a boost to help to turn the starter over. As Otto has said. I add a Bosch relay down by the starter to help. Even though I was not having problems.

Once you have the car sorted out. You can reach into the car, turn the key, and the car will start.

A side note: If your car will be sitting for long periods of time, because of the UK weather. You might consider adding a electric fuel pump. It will help save some wear and tear on the Starter and battery.


http://forums.pelicanparts.com/uploa...1473004700.jpg

In addition to my previous post regarding the hot start helper relay and Jaems's example, below my installation version and a simplified circuit diagram to build your own.

I used an aluminum bracket to mount the relay to one of the starter mounting bolts.

Left the factory circuit and right the circuit with the hot start relay.

http://forums.pelicanparts.com/uploa...1473029948.jpg


Otto

Sorry, forgot the practical version of the circuit as I installed in my '68.

http://forums.pelicanparts.com/uploa...1473030278.jpg

Otto

well done jaemes and otto .... owners of 9/12's know that the starter issue can be a pain... mine works perfectly right now but i will be doing the relay soon because it has a great long term pay back.... bob