"David P" wrote in message
o.uk...
My lawnmower has a Honda GCV 520 engine fitted and I find it is running
too rich and 'hunting'. Nowhere can I find how to adjust the mixture,
everything says 'refer to dealer' which I'm reluctant to do! - any
pointers where to look would be greatly appreciated.

Air filter is new this season and clean and no air intakes are blocked.


I used to own a machine with a similar Honda engine and STR there is no
mixture adjustment. Have you cleaned the spark arrester? if that's badly
clogged it can cause bad running. Badly adjusted valve clearances can cause
bad running as well. If you don't have a maintenance manual take a look at
this link.
https://www.honda-engines.com/Engine...X37Z5Z6110.pdf

Mike