Author Topic: Ill fitting air slide  (Read 2625 times)

0 Members and 1 Guest are viewing this topic.

Offline gpobantam

  • Member
  • *
  • Join Date: Aug 2011
  • Posts: 18
  • Location: S.W.England
Ill fitting air slide
« on: 12 Apr 2012 at 18:53 »
Evening all.

I have aMark1VSport. Starts O.K. but a couple of times I have had trouble with the choke slide becoming detached from the plunger on the carb with the obvious result of very lumpy running on the affected cyclinder. It seems to me that the air slide merely grips the plunger rod when it is passed the first of two indentaions. Should the top one of these be springy to act like a captive mechanism on the plunger? Mine has no give at all. The plunger rod passes it rather stiffly but not stiff enough to prevent the slide dropping off.

Can the slide and plunger be bought seperately?

Thanks Mick

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1861
  • Location: Hampshire, UK
Re: Ill fitting air slide
« Reply #1 on: 12 Apr 2012 at 20:28 »
Mick,
        The air slide has 2 narrow slots cut across it near the top - the portion between them is punched in to locate in the reduced diameter near the bottom of the plunger - thus preventing it from being removed again. With the passing of time, the plunger and the bore of the slide become worn and eventually the slide drops off - as has happened on your machine. Possibly, only Douglas fitted this type of choke assembly on Amal 274 carbs, so it is unlikely that anyone is making repro parts for them. Personally, I have never found these choke assemblies very effective, or easy to use. The Mark series engine rarely needs the choke - I have always found that a cold engine starts easily if the carbs are 'tickled' first - with the engine getting warm enough to run smoothly as the fuel level drops back to normal. All my engines are now fitted with carb tops intended to be used with cable operated chokes - with threaded plugs filling the holes for the cables - no more problems with self dismantling chokes, or weather getting in around the poor fitting assemblies.

           Regards,
                       Eddie.

Offline gpobantam

  • Member
  • *
  • Join Date: Aug 2011
  • Posts: 18
  • Location: S.W.England
Re: Ill fitting air slide
« Reply #2 on: 13 Apr 2012 at 18:34 »
Thanks Ed.

I will follow your example .

Cheers Mick