stop motor

[rabbit]

4.5 HP Silver Century has been rejuvenated and running fantastic since. Always creates a discussion topic at the boatramp ... small issue is - that it starts SO easily .. that she doesn't want to stop ! ! ! .. when idling into the ramp (or beach) and I close the throttle , the motor will just be at the point of only just kicking over and wont die - so I just close the choke to kill it. The throttle adjustment appears fine and the slide is hitting the bottom of the carb barrel OK. I seem to recall in earlier years it used to die quite happily. Any suggestions ? It is a small issue - although now that I have a custom throttle cable on a 14foot runabout with steering - and the motor is direct-drive, I have to leave the station and close the choke back at the motor. (lack of speed and agility in doing so when single-handed - can cause issues with boatramps and unsuspecting bathers ! !

[Nudge]

Could the needle have a bit of wear on it? When you throttle down it is not seating in enough. Just a thought.

[headdownarseup]

I suspect that your "custom made" throttle cable is either slightly too long or short! (probably a smidge short)
I would remove the carb from the cylinder,shine a light from the back side of the carb inlet and if you can see the slightest slither of light from the bottom of the carb slide then an adjustment or another cable is the way to go. (you will of course need to remove the inlet cowl first to see into the carb)
With the throttle shut off you should see no light at all, which would mean the throttle slide is completely closed off and the motor will stop with no fuss.

You dont mention whether the carb is villiers or amal. (both have a similar adjustment for the throttle cable)
Only the Villiers and Bing carb has a needle on the slide, the Amal carb slide just runs up/down within a small guide.
If you have the amal 46n carb, worth taking the top cover off to have a peek inside at the jets. It could also be that one of the jets is protruding just a bit more than it should do hence why the motor will not shut down completely.Occasionaly the slide in the Amal can get a bit "sticky" so well worth a good clean.

See how you get on.

jon

[rabbit]

Thanks Jon, apologies - it's an Amal ... I will dismantle all and clean and recheck. I have noticed that if anything - the cable outer might be a tad short , but not much... the adjustment on the mixing chamber cap maxes out and the outer cable tends to sit high, rather than too firm..

[JERSEYMAN]

I recon that the slide is not closing properly due to the return spring either weak or just not up to the job due to the extended cable as long as the cable is free, better/stronger spring probably needed.

[supersaint61]

check that the nipple on the end of the cable is not protruding from the bottom of the slider stopping the slider from going all the way down