ignition switch - no 12v

[kiwikol]

I'm trying to help a friend with his boat out of the water doing a job which required the engine to be disconnected and shifted forward temporarily. The engine, a two cylinder Ford, has now been replaced but we can find no 12v at the ignition switch. The switch has JC printed on it and has 6 terminals (G1 and G2 joined, B1 and B2 joined, S, and M) None of these have any power! The battery has connections to the domestic fuse board but no obvious connection to the ignition switch. In fact the battery's only other +ve connection is the heavy cable direct to the starter motor. Where on earth does the ignition switch get its power from? It was running fine and no work has been done in the electrical circuits apart from disconnecting the engine wires prior to moving the engine. I am completely at a loss for ideas and would welcome suggestions. I have checked that a hot wire from the battery to the starter solenoid works fine and the engine turns over. There must be some obvious solution which would enable us both to sleep again!

 

[chasroberts]

Have a quick nose here:

http://www.boatfix.com/how/switch.html

Might give you some ideas as to what you should be looking for. If not then it might be time for an electrician to have a look at it. Good luck in any case.

 

[geem]

Check that there isn't a relay on the engine. My perkins has a relay for the glow plugs and one for the ignition switch. It also has a thermal trip. Either it these stop power on the ignition circuit

 

[nigelmercier]

Main breaker?

 

[kiwikol]

Had a look at the boatfix page (thanks for the link) and all the switches shown have a +ve supply - that's what I would expect but this one doesn't seem to have any such provision! But it used to work and nothing has changed - got me beat! I'm beginning to think it's via bluetooth!! There is a 'magic box' which has a loom and connections to the alternator and one of the the main solenoid terminals (not the direct big battery connection terminal) - not certain what it does but it looks technical ! Really appreciate your help - thanks.

 

[kiwikol]

Main breaker?

main breaker??

 

[nigelmercier]

main breaker??

A big switch that isolates the supply, or a 0-1-2-Both switch.

 

[david_bagshaw]

seeing the engine has been moved I would look for a broken wire on the engine. Frequently the engine electrics are connected to the large starer motor connections, so I would start there.

Goodluck.


If you can get vellman products there, they do a good wire tracer which puts a signal on a wire, & you search out with a recieving probe

 

[boguing]

A lot of ignt switches do take their power from the starter - which is also connected to the battery and alternator.

 

[kiwikol]

Correct and a 'positive' result! The isolated stud (not the one that has the strap to the starter brush) on the solenoid takes ALL the wires (- leaving the other main solenoid terminal bare). This then connects directly to the ignition switch - seems obvious now! We had reconnected one pair of wires to the wrong solenoid terminal. Many thanks to you all - not easy trying to understand wiring problems from across the globe. Much appreciated.

 

[nigelmercier]

We had reconnected one pair of wires to the wrong solenoid terminal...

Easily done. When I am removing wires from several terminals, I bunch them together with a cable tie.

 

[jwilson]

Two cylinder Ford - a very very rare beast - maybe more unicorns around.