My Honda 4str mower engine is sounding a little unwell.

Have just given it it’s new year service (plug, oil, filter) but it runs lumpy, stalls when the choke is opened, and has barely enough grunt to engage the blades without stalling.

Its probably my fault for leaving old fuel in the carb over the winter so I think I need to take the carb off and give all the ports and jets a good clean.

Is any “cab cleaner” solvent from that auction site OK for the job? Strip, spray, soak, wipe, rebuild and reinstall yes?

I bought the cheapest, from eBay when the strimmer was playing up. Gave it a good dose and it’s been fine ever since. Not sure if they come in different flavours but mine was hardly a discriminating purchase.

Spray Easy Start into it. Burns hot and clears out any crud

If it starts and runs, dump the old fuel, put in Shell Advance and start it. Spray carb cleaner into the inlet.

Could be as simple as water in the fuel. Cessna 152s have water drains in the wings for just this reason – drain and confirm no water or expect to practice a forced landing!

I’d strip it and use any old carb cleaner (watch out it’s colder than a super cooled ice cream) and preferably blow it out with an air line.
I’d be wary of easy start, especially as the mower runs already.

cheers guys.
Sounds similar to advice from pub-mechanic-o-mate.

Took the carb off tonight, it’s not a serviceable unit by the look of it, so will blast with cleaner. It has clean fuel already.

Don’t forget to drain all fuel & run machine until it cuts out at end of year. Fresh fuel in at start of new year & modern petrol only good for max of 6 weeks due to ethanol content. If you’re not going to use in that time, consider a fuel additive that stabilises the fuel. The ethanol takes in water…which your mower really doesn’t want to run on.

If it’s the usual Zama carb you should be able to get a rebuild kit for it, also the Zama web site has useful diagrams of how these things work and where it might be gunged up . I had a similar problem with a Stihl carb recently, a can of cheapo Toolstation carb cleaner eventually sorted it but getting the tiny channels free of gunk was non-trivial.

Rio, unfortunately it’s some kind of Honda special.

Zama stuff I love on the chainsaws.

Good luck then – without a diagram I couldn’t begin to figure out which holes came out where and hence which were blocked!

Stoner, our old Honda mower was bad for something similar. Check the bowl at the bottom of the carb. It’s a Cadmium plated colour held on with a single bolt, but there is also a drain bolt. Water can get into the fuel and splits it causing rough running. I used to take the bowl off completely and clean it. Sometimes tiny bits of rust would find their way into the carb jet. Taking the carb off and checking the jet is clear is the only way. Reasonably quick job once you’ve done it once or twice,

Cheers lads, but it’s not one I can open up.

Cheers lads, but it’s not one I can open up.

Are you sure? It had to be put together so it must come apart unless it’s some cheap piece of crap, which I wouldn’t expect you to have!

annoyingly, whilst all the Honda carb vids show the carb model with drain and removeable bowl (goto 3mins)

[video]https://www.youtube.com/watch?v=-0BKW7hrzfE[/video]

mine seems to have a bowl without a drain and that doesnt seem to want to come away from the carb body so I can clean it.
Its like this one on eBay, once you’ve undone the bolt at the bottom of the bowl, the bowl still wont come away….
http://www.ebay.com/itm/16100-Z0Y-M41-BB75FA-GENUINE-Honda-GCV190LA-S3C-S3L-engines-CARBURETOR-ASSEMBLY-/261353274228

Try spraying it up the air intake with cleaner first before doing a Moly and taking the whole thing to bits. Leave it for a bit to dissolve any gunk, repeat to fade.

yep, that’s the plan.

I think you’re just being a bit of a wuss 🙂 It’s a keihin carb which are pretty good.
If you cant clear it by spraying through the intake give it a bit more welly. Probably gummed up inside.

I shall hold you responsible if I end up appearing in this thread:

http://singletrackworld.com/forum/topic/dont-know-my-own-strength-andor-stupidity

Mine does not just come away as at 2m33s

🙁

[video]https://www.youtube.com/watch?t=154&v=0BA_U4jQHzQ[/video]

just got to do some work for the day job, will go back out to the workshop in a bit and lean on it some….

The bowl contains the float and the jet. There will be an O ring sealing the bowl to the carb body, unless they have glued the two halves together. Get into it man.

Get medieval on its ass then get Molegrips on its insides.

done it.

It did just require a little less girlishness on my part.
😳

Got to pop out and get something to clean it with now.

ya big girl 😉

If you’ve got a compressor blow everything out, the holes on these things are really small and it only takes a small bit of poop to mess things up.

fortunately I have a nice little compressor

Not the product you want but always makes me chuckle when I see it at the local motoring shop:
null
The bits of shite in the bowl are sterling advice. Been there recently with a Honda 4stroke.

all done, and running sweetly.
cheers chaps.

Did you find any debris or water in the bowl or jet?

not that I could see, but there was a bit of brown varnishing on the choke paddle and walls of the chamber so it’s not unlikley that a jet had a slight gummy restriction causing the over lean mix.

You can unscrew the jet core the fuel goes through, it has a tiny internal diameter. With my dodgy eyes I can barely see through it. A micro dod of crap can bung it up and screw the mixture.

Nowt more satisfying than getting an engine to run sweetly.

Aaah, I like a happy ending and no STW arguments (yet) 😀

Don’t forget to drain all fuel & run machine until it cuts out at end of year. Fresh fuel in at start of new year & modern petrol only good for max of 6 weeks due to ethanol content.

Hmmm, I put mine away after the last mow for the last two years without draining or anything and each spring it has started first time. I *know* I should look after it better but I don’t and it doesn’t complain.

(Briggs & Stratton engine)

Me too but it did take the wife half a dozen pulls to start it for the first cut 😀