k/b 7.5 pro no spin start

[bob miller]

sometimes when starting my 7.5 pro ob all I need to do is clip my igniter to the plug and the motor will almost start by itself ....is that a good sign or not so good ....has anyone else have this happen ??? thanks.....bob

 

[David Santistevan]

I have see this with motors especially when you pull the plug coils. I have plug the igniter on the head have the engine "POP". I think its normal bob depending on the combustion characteristics of your setup.

D

 

[moparbarn]

If the piston stops.where it covers the ports, the trapped fuel charge won't evaporate &can fire when the igniter is connected.

 

[Steve P]

Yep, I had an old K&B 3.5 outboard that started more than once just by attaching the glow driver. ( it was pretty wore out not much compression left)

 

[El Zorro]

I remember seeing my Dad start his inboard boat engines with his thumb on the flywheel bumping against the compression. I always thought this was too cool! Mostly he used a leather shoelace that would grip in the flywheel groove. That was before electric starters. When I was flying controline Combat models we went to using very thin speed props that you could not flip the engine through compression to start it for fear of breaking it. We would position the right side of the propeller up against compression and with a bit of prime in the exhaust and the battery connected, take 2 fingers and hit the right side of the prop downward, which would then "bounce" off of compression, firing the engine. AHH, the good 'ole days!

Dick Tyndall

 

[Robert Pickard]

Like Robin said it is where the piston has stopped it has happened to me on bot outboard and inboard

 

[the german]

Had the same phenomenon with an old 3.5 K&B OB ..... i could also start it with my thumb ( like Steve said ....... "it was pretty wore out not much compression left " )

Alex