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Last year my mower started running for a bit then spluttering out. I'd start it up and get a bit out of it, at the end of the year it wouldn't start at all and I duly stuck it in the shed with a promise of fixing it before it was needed.
Needless to say I've waited till now to look at it again. Initially I thought it might be off fuel or a blocked filter so I stripped the fuel side, drained the petrol and checked it out. Filter was fine, had fuel right up to the carb and the carb appears clean and working. Filled with some new fuel too. No joy. Next I looked at the dead mans handle, pulling it released the brake and made a switch, I adjusted the cable tension slightly and at the same time adjusted the brushes on the drum. I also gave all the electrical contacts a wiggle. This time the mower did fire up but came to a halt as soon as it started. If anything it now appears to over rev and cut out. Adjusting the choke is not doing anything, it either starts with it fully open or doesn't do anything with it cut back even slightly.
To compound these problems the air filter is broken off and has been for a while I have tried to adjust the mixture but its needle in a haystack as the mower isn't running. The mower is a very cheap model too and I've had a few years out of it, I'm only going to fart about a wee bit more then buy new but I did want to give it a final try.
Thanks if you've read all that, quick version is:
try to start - over revs and cuts out.
How does the sparkplug look ?
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Admittedly thats the one thing I haven't checked as I couldn't find a socket. I'll have a better look for one today.
Annual spark plug change a good and cheap routine.
Let the carb run dry at end of season, don't let fuel sit in it over winter.
If carb is varnished, get some carb cleaner in there
if my air filters anything to go by after a seasons cutting.
youll probably find your engines full of grass , dust and dirt.....since you dont have a filter.
i sugggest rather than buying big shed guff getting on gumtree or down your local machinery shop and looking for a decent nick used trade model . much more robust.
I have a 2 stk suzuki engined allen flymo that will take the tops off your concrete copings and not grumble for the rough and a qualcast 4stk cylinder mower for the bit i pretend is actual lawn (ie the front garden)
both in total cost much less than 1 from the big shed mountfield guff my parents religeously replace every 3rd or 4th year
My money would be on dirt in the carb jet. I've cleaned out the jets on Honda mowers, there are clips on YouTube, yours might be similar
Check the spark plug and clean the carb as others have said. On my mower its gets erratic when the paper diaphragm gets worn and inevitably tears. Revs go high and low known as hunting. If everything else is resolved I'd look at that as I've replaced this piece twice on mine (Briggs and Stratton). Also recommend you resolve the missing air filter.
Fresh fuel always made a big difference for me.
Had mine serviced/fixed as it wasn't great last year and refused to start last week. Petrol had gummed up in the carb and they have advised using Aspen fuel, doesn't go off or gel. £15 for 5litres, might be an end of season thing!
Spark plug check plus isn't there another little electrical component which can fail ? As above fuel goes off and also evaporates and leaves a residue in carb etc.
TBH we had a 15yr old mower which wouldn't start one year amd after trying various self help measures we bought a new one 😳 cost of someone looking at it seemed too high
Briggs & Stratton?
The carb is a bit of a funny design, so would need the air filter to get the right mixture. Over-revving like that is what happens if it is running very lean (starts on the petrol from the primer button, then rapidly runs out of fuel).
If cleaning the carb out doesn't solve the original problem, it is likely that the rubber diaphragm (part gasket, part functional) between the top and bottom of the carb that needs replacing (about a fiver for the part) - can give all sorts of problems.
Seagull's nest in the grass box?
Seagull's nest in the grass box?
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