Starter firing in when engine running

[And]

Strange one this. The engine (cerb sp6) starts first time from cold, warms up for 5 mins then suddenly there's a screetch as the starter kicks in with the engine idling over. When i hit the off button the engine stops firing but the starter keeps turning over, only stopping when I 'stall' the starter by putting it in gear.

Same thing happens when I try again an hour later. It's like the alternator is energising the starter when the ignition has been cut???

Any ideas?

[Buffoon]

Put a meter or 12v lamp between solenoid coil and earth return. Need to determine if electrical problem or mechanical.

Does it do it every time?

If you are brave you could start her up with airbox off, then carefully remove solenoid lead, or better still put a switch in line for testing.

Should not be too difficult to diagnose providing not intermittant

Interested to hear how you get on. Good luck

[Speed_6_2001]

The exact thing happened to me a couple of months back. I didn't think to stall the engine but just drove off as I needed to move the car pretty sharpish at the time. Fortunately after 10 metres or so the starter motor suddenly stopped turning over and the problem hasn't arisen since (touch wood).

Let me know how you get on in case this little gremlin comes around again.

[And]

Happened first time out of the garage after a lengthy lay up so I might be a problem that disappears as your did.

But I'm expecting to be out there with my multimeter tomorrow morning...

[And]

I went in with my multimeter on Saturday.

- continuity across the starter solenoid when ignition turned off
- found the energising wire constantly live
- fuse 5 (starter wire) live with the ignition off. Actually when I put the fuse back in the car started. nuts.
- so maybe the immobiliser or starter relays are playing up?

sound familiar?

[Buffoon]

Don't know if it is any help, but mine is a speed six starter and I know that when you test the solenoid by putting a feed on it, it will try to turn over without the main power cable fitted to the motor. Not directly related I know, but may stop you going off in a tangent.

At least you are getting it to fail under test. Keep us posted

[And]

Any idea if the starter switch is linked into the solenoid on the live side or the earthing side?