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Collection, Preservation and Display of Old Lawn Mowers

stiff Choke on amal 379

I'm guessing this is a simple mechanism.

The pull-choke on my Ransomes Marquis (BSA Sloper/F12) is very stiff.


I'd rather it worked smoothly, both for ease of use and long life. Can anyone point me at a diagram

that would allow me to disassemble, clean and lube?


(I'm sort of taking for granted that disassemble, clean and lube is what's called for)




wristpin Mon, 29/07/2013

The illustrated parts diagram that Hillsider has posted will show you what is what but "clean and lube " is the way to go  - they get gritty and stiff. You can alter the friction a bit by adjusting the centre nut but you need enough stiffness for the choke to remain "on or off"

bugbear Tue, 30/07/2013

Thanks for the link.


For my own purposes (since I happen to work in the pre-press industry, and have the tools)

I've burst that document into separate pages, and made them "right way up".


Would this reformatted version be of interest to the group? If so I could send it to the site owner for hosting.



hillsider Tue, 30/07/2013

Glad to be of help re the information on the F12 engine, you should not have any trouble getting the choke to operate feely once you have cleaned it. Re the document I am afraid you are not making much sense to me (I understand spanners better), I have just looked at it online and it opened fine and was displayed correctly so I am unsure how it could be improved. How the site display manuals etc is in the capable hands of a site administrator/club member - maybe he will see your remarks and post a comment. Ray.

bugbear Tue, 30/07/2013

That's most interesting - the version I downloaded a while ago is different to the one I get by following your link, which is (as you say) just fine.