How To Clean A Honda Carburetor

[email protected]

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Here's Honda's official how-to guide for cleaning a Honda mower carburetor. Modern fuel mixtures aren't so great for small gas engines, and if you're having trouble with rough running, only running on CHOKE, or poor idle, there's a good chance the carburetor has some slime, gunk or debris somewhere inside.

sample_zps6wlyraak.jpg


This guide will show you how to properly inspect and clean the carburetor on most small Honda OHV engines. DIY and save some money and time.
 

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SeniorCitizen

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How often is a seat worn to the point, on a Honda or any other brand, that replacement is required?
 

[email protected]

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How often is a seat worn to the point, on a Honda or any other brand, that replacement is required?

Seat material is better than it used to be, as are fuel filters, so it is not as much of an issue as it was 20-30 years ago with poor-quality rubber and dirty fuel.

That said, with all the ethanol fuels today, the jury is still out on how long a modern seat will survive. I can tell you I've not see a truly worn-out one in many, many years. Use good quality fuel, don't allow it to go stale, check/replace the fuel filter, and I'd bet the seat would last the life of the engine.
 

ft_motors

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As long your carburetor is not leaking fuel, you shouldn't worry about the seat. If the seat really gets worn, the level in the bowl will rise and eventually start leaking. But that is not the case with today's carbs. 80% of all today's carbs problems are related to ethanol in fuel.
 

TheDIYTool

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I haven't seen a worn seat, but recently I have seen a clogged seat. As [email protected] mentioned, "there's a good chance the carburetor has some slime, gunk or debris somewhere inside." I had to clean the carburetor due to an oil overfill. Oil was leaking out of the governor, clogged the carburetor, and saturated the air filter, restricting air flow, and fouled the spark plug. After a good cleaning and correct oil fill, it is running like a champ. I have started a series of videos and the Honda is included in them. https://goo.gl/zCfAud
 

PTmowerMech

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As long your carburetor is not leaking fuel, you shouldn't worry about the seat. If the seat really gets worn, the level in the bowl will rise and eventually start leaking. But that is not the case with today's carbs. 80% of all today's carbs problems are related to ethanol in fuel.

There's worse things in gas than ethanol.
 

Born2Mow

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► I just rebuilt one of these carbs on a 21" walk-behind I got from a neighbor. The problem generally isn't clogging of the "Main Nozzle", it's clogging of the tiny jet that's accessible under the "5x6mm Screw". That thing has a microscopic hole that can clog at the drop of a hat.

► Float seats don't generally give issues as they had in the past. Some newer carbs may have a viton tip on the float needle to promote sealing. Those will eventually harden in 15 years and start to weep. If you can see a permanent indentation in the viton, then it needs replacing.
 

StarTech

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And some problems with float needles and seats can not be seen by the naked eye which why a pressure leak down test (pop off test) should done. The carburetor should be able to pass a 15-30 minute leak down test when the inlet valve system is sealing good. This especially true on 2 cycle cube carburetors where imperfections are only visible using a 10X loupe or similar magnification device.

Seats can corrode especially when exposed to acids in the fuel. And water combined with the fuel and air does create corrosive acids. I have seen hairline tracks in seats using the loupe here that the non replaceable seats have to be re-cut to remove them with a six point counter sink with correct bevel angle.

Seats and needles also sometimes gets embedded with foreign materials leading non sealing conditions. Usually on most needle tips only a small portion of the tip is the actual sealing area which is why a ring groove develops.

With on the subject Honda carburetors they are known for poor needle/seat sealing which why many of their walk behind mowers comes with a fuel shut off valve in the first place.
 

Hammermechanicman

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Funny how seats and needles are still a problem. Anyone who works on really old equipment or old gas tractors that have metal tipped needles and metal seats know you ALWAYS turned off the fuel valve or next morning you had an empty tank. It was in the instruction manual. The old medium and large 2 piece Briggs flo-jet carbs were so bad they put a drain hole with a felt seal in the carb throat to drain the gas so it wouldn't fill the engine with fuel. We put a man on the moon 50 years ago and we still can't make a fool proof needle and seat.
 
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