Electrical question SIIA

Hi,

I am re-wiring my 1964 SIIa. Negative earth.

I started from scratch and here is what I have completed so far:

Battery:
+ To remote starter solenoid
_ To Chassis

From + of Solenoid to BAT positin of ignition switch.
Acc/Ign position of start switch to Fuse box (main lead)

From Start position of Ign Switch to the "S" post of the remote solenoid.


So far when I turn the start switch from OFF to first position (Acc/Ign) I get voltage to fuse box. All good.

When I turn the start switch to "Start" I can hear the solenoid click and I am reading 12V at Starter lead of solenoid. When I release the start with from crank, I hear the solenoid click and no power to the solenoid post going to starter. All good.


Now where it gets puzzling is once I connect the Starter cable to the solenoid and try to start. Nothing!?! No click, no cranking.
However if I move the starter cable to the same side of battery lead on the remote solenoid and turn ign switch to start then the starter engages.

I thought that the remote solenoid mighthave been faulty so I got a new one and same thing???

So why if I get 12V on the starter side of the solenoid the starter doesn't engage?

Any ideas?

Thanks.

(I'll try to post a video later. Easier to explain.)

Can't visualise what you mean but are you sure the starter works and that the starter is earthed properly. Test by running a jump lead direct to the starter. Test the solenoid by shorting the two main current posts.

Also, have you considered using a power probe (basically a lamp on a stick) rather than (I assume) a meter). You can often get an apparent voltage that wont actually support a load which can be confusing.

Have you swapped the starter? I think they're different for -ve and +ve earth, sounds like your connecting +ve out of solenoid to +ve of a +ve earth starter not good...

dominicbeesley said:

Have you swapped the starter? I think they're different for -ve and +ve earth, sounds like your connecting +ve out of solenoid to +ve of a +ve earth starter not good...

Click to expand...

ignore the above comment, starters don't care about polarity

Remember the engine and gearbox are not earthed to the chassis as they are on rubber mounts obviously you have some kind of earth as the solonoid is clicking might be worth running a jump lead from nagative to the engine block (out of the way of any moving parts) and try again??

I would go down the road of doubling the neg lines from the engine to the chassis get a realy good earth as the currant is quite high