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Collection, Preservation and Display of Old Lawn Mowers


Hi, im just getting into lawn mower repairs of old.

My first project is a more recent old mower, a Webb Diplomat 350. I bought it as a non runner and have gone straight at the carb. The inside of that thing was pretty bad.


To the question.


Carb setting, i cannot find information on it.

Where do you guys get your info on various carb setting ? I know there are books but cannot find one on the DELLORTO FHC20.


Any help appreciated. 


hillsider Fri, 11/04/2014

Welcome to the Old Lawnmower Club, i am sure that the engine on your mower is of Tecumseh origin if not you will still find the information contained in the manual attached helpful as it is mostly common information that can be applied to many carbs.

hopefully this will work as a link if not copy and paste to Google or similar.



wristpin Fri, 11/04/2014

This was the carb used on the Tecumseh derived engine fitted to the Webb, I believe that Tecumseh's part number was 23020142 and you will find the basic configuration in the link supplied by Hillsider. 

I think that it will be a "post emissions" version with no adjustable main jet under the float bowl which cuts down the scope for fiddling (aka finger blight!) so you will probably have just a throttle stop screw and an adjustable slow running  jet.

if the carb is free of contamination the fixed main jet should cope with all eventualities but if  fuel flow is restricted by gum etc and the engine is hunting it is sometimes possible to tune this out by rich ending the slow running jet at the expense of smooth idling .

Follow the instructions in Hillsider's link and see how you get on . If you can't sort it  I am sure that we can offer further advice but it's so much easier with the metal in font of one than offering theoretical verbal advice!