Outboard ignition system

[Silkie]

It's a given in the automotive world (or used to be) that if an engine is to be turned over with spark plugs withdrawn, the plugs should be earthed to prevent damage to the coil - or is it the capacitor?

Anyway, if I do the same with my outboard is it necessary to earth the plugs if the kill switch is open?

[DaveS]

It's over 10 years since I've had to fiddle with petrol outboards, and then only my last one was fitted with anything as sophisticated as a kill switch, so my memory may well not be reliable. As I remember, however, the kill switch operates as an earthing switch which is held open when the clip is in place. The wiring diagram in the manual should confirm (or, of course, refute )this. If I'm correct then with the clip removed the LT ignition circuit is disabled and no HT will be produced on turning the engine over.

[sahona]

Dave's right, killswitch does what it says on the tin - also if you're turning it over just to spread the lube or ease it's creaking bits, it's unlikely to be fast enough to get much voltage anyway.
Why not earth the plug and check the spark is good while you're at it?

[Silkie]

I see I've not replied on this thread. How very rude.

On the day prior to the launch of the good ship Silkie this year I gave the little smell a dozen or so pulls on full choke with the kill switch killed. The notion was that the engine would be bathed in oil after the petrol evaporated and this, representing the complete winter maintenance schedule, resulted in a start and subsequent utter reliability (touch wood) at the second pull.