Twice now, I couldn't get my 200cc Honda engined mower to start, despite it being 'Easy Start'(and despite it having a petrol additive in it). It played up last year and I had the carb off and cleaned it right out, but it still played up when I eventually got it to start. In desperation I grabbed a can of Wynns Carburettor Cleaner; took the air filter off and blasted a load directly into the carb (and probably the compression chamber) until it was dripping out. Wynns Carb Cleaner doesn't evaporate as quickly as Wynns Brake Cleaner, but the mower fired first time. I had to do it again yesterday with the same success; so I have just tried it in a Ryobi Strimmer - same result. It will try it in my chainsaw next! Saves a lot of effort.
I removed, cleaned and gapped the spark plug, then charged the battery (not lithium) and it fired up no problem. Must get a tin of carb cleaner for next weeks attempt
I did all that to mine although I don't have a battery - it usually started second pull on the rope. Why it went wrong, I have no idea, unless something in the carb linkage has got all bent.
Might just be residue of old fuel over years of reliable running? Mine could use a new air filter but haven't found one cheap enough yet..... Henry hoover on the old one works a treat....
Funny you should post that today. I got the strimmer out today, first time this year (it’s 7 years old), had loads of fuelling issues last year after the winter shed hibernation. Stripped the carb down 3 or 4 times over last summer but it still played up but managed to limp through the season. I’d bought a can of Wynn’s a few weeks back, so today, when it wouldn’t start I reached for it. I thought I’d have to strip the carb and clean it up with the Wynn’s but no. The instructions say “remove air filter and spray into carb body”. I didn’t even have to remove the filter, just opened the access hatch, opened the throttle and gave a good spray. It started 1st time and then ran for 6 hrs non stop save to refuel. for Wynn’s Carb Cleaner. It must be made by Ronseal as it does exactly what it says on the tin.
What I need to do now is getting running properly because it is still hunting - I suspect the pilot jet is the problem, but it is one of those that is sealed in very well - I just can't get down to any slotted head to remove it, bloody stupid idea.
Clean / replace air filter first - my mower hunted badly when off load until I cleaned the air filter. It would be fine when on load and mowing but hunt when off load and stall on idle. Easy check if you can't get to the jets
It isn't the air filter - clean as a whistle. The mower hunts when under load as well, a regular droning sound, drives me mad. All the throttle settings at the had control have gone skewed. The idle stop screw adjustment helps, but it still hunts.
Fair enuff - out with the jets then - unless soaking in carb cleaner overnight cleans them (need to stop it evaporating)
Used a can of brake cleaner on the outside; then a can of carb cleaner on the inside once it was stripped apart - I reckon there must be something jammed in between the pilot screw hole and the pilot jet - I actually meant it is the pilot screw I can't remove - the pilot jet comes out easily.
And to think that people think working on Ducati's is difficult I'm sure you will be able to fashion a bespoke lawnmower carb tool kit which you could sell to the public
I've found with stubborn resin/varnish build up on jets, or in carb bodies, the most effective stuff to soak bits in (overnight) is acetone, often sold as paint thinners, or in smaller quantities (250ml) as nail varnish remover - but read the label, some now boast to be acetone-free
Also useful if you're set for jet/carb cleaning action, is a set of these (not necessarily from this seller, with whom I have had no dealings) https://www.ebay.co.uk/itm/Carburet...=1233973382333aff5f5349bd464cb99eb09cf29431d8
