I have a Honda GX240 engine on my log splitter that is giving me issues. If I don't close the fuel shut-off when I am done, the fuel runs out of the tank (mounted above the engine) and into the engine. Twice it had filled the crankcase with gas, diluting the oil, which ran out like water when i went to change it. The other time, it filled the cylinder, hydro-locking the engine. Each time the machine sat for about 12 hours. It was sitting level, and was not moved at all from the time it was shut down until I next tried to use it.
The carb was replaced several of months before this started happening (cheaper than having the old one rebuilt). The small engine guy I took it to said that Hondas (among some other brands) are known for this problem when the tank is mounted above than the engine. He says the float in the carb just sometimes isn't enough to shut things all the way off. I don't have the problem with my Honda GX-powered generator. In fact, I've never owned any other small engine that had this problem.
I generally make a practice of using the fuel shut-off, but it's a pain in the neck having the engine inoperable if I forget. Is there something I can adjust that will prevent this from happening if I forget to use the shut-off?
My thoughts are that the float should apply enough pressure on the needle to prevent gas flow. Remove the bowl, float, needle and seat. There could be a bit of trash preventing the needle from seating. You may need to slightly bend the tab on the float which would add more pressure to the needle. Do some tinkering.
Quote from: Magicman on November 04, 2017, 10:07:08 PM
My thoughts are that the float should apply enough pressure on the needle to prevent gas flow. Remove the bowl, float, needle and seat. There could be a bit of trash preventing the needle from seating. You may need to slightly bend the tab on the float which would add more pressure to the needle. Do some tinkering.
Supposedly, the small engine guy I took it to already checked that and said it was OK, but I'll take a look.
Obviously it is not OK, or it would not be leaking past the needle/seat.
Sadly it is cheaper to replace than to "repair" but carburetors seldom actually need "rebuilding". They need cleaning but at hourly rate, it is easy to get "upside down" on cost unless you are doing it yourself. I recently had a generator carburetor that I had to pull the third time and used a couple of cans of carburetor cleaner before I finally got it going. Neglect is a bad thing and I never allow ethanol in any of my small engines.
I had the same problem this week. I have no problems working on small engines.
I think my carb somehow got a small crack in it. I did not have a float or needle
problem. To check for that when you have the carburetor off and empty blow in the
gas line. You should be able to blow air in. Now turn the carburetor upside down.
Blow in the gas line again. You should not be able to put air in if the needle is working.
I had to replace my carburetor. I could not find why it dripped. Your carburetor will also
leak if the float loads up with gas and does not float anymore. The junk they put in gas
today is bad for doing this. Carburetors are so cheap on E-bay that it's not worth the time
working on them today. You can get a new one with gas line and gaskets for $13.00 off
E-bay with free shipping.
If this was not a problem prior to the carby replacement, maybe swap the old needle and float with the new, and see if that makes any difference? It's possible the new unit has a mismatched needle and seat, and/or float, or perhaps there's something in there preventing shutoff.
A roaming strand of hair would do it.
I've a number of Honda GX engines, and don't recall having that problem with any of them. In one example, the gas tank is mounted remotely, and significantly higher than the carb.
More info:
The old carb was replaced a few months ago. It was dripping gas out the carb any time the fuel flow valve was open (including when the engine was running). I did not have the time to mess with it myself, nor am I all that great with carbs, so I took it to the local small engine guy to replace and give things the once over (I bought the splitter used).
I'm not sure when the new carb developed problems. Since I normally close the fuel shut-off if it's going to be off for more than a quick lunch break, it could have been this way from the start. It was used only a few times over the course of several weeks before I noticed problems.
I always use non-ethanol fuel in all my small engines. The filler neck on the splitter's tank has a fine mesh fuel screen (not that I've had problems with dirty fuel on any of my other engines that lack that screen).
I did once forget to close the fuel shut off when towing down the road (bumpy road, splitter has no suspension). I've been advised by multiple people to always close the shut off prior to towing. I'm not sure how that could do anything other than a one-time flooding as things bounced around and more fuel squeezed by as the float bounced.
I'm guess carb was either defective from the start, or I somehow got a piece of crud in there. Carb is OEM, not a Chinese knock-off (I figured I'd go with the more expensive option, since I wanted maximum reliability). I'm not inclined to think that the float is mis-adjusted, since the guy checked that when I brought it back in (he's a one man shop, and highly respected in the area).
Never heard of it with Honda's, but the newer Briggs have similar issues during any traveling if the shut off is not closed. They flow straight into the cylinder, locking it up, its been described to me as a faulty float design,
It might have been travel-related the first time it happened on my splitter, but for the others, it was stationary the whole time. It is possible the float or valve got damaged.
It is getting by the needle/seat so it would be trash or the float riding too high and not putting enough pressure on the needle. I doubt wear. You do need a filter between the tank & the carb.
Quote from: Magicman on November 06, 2017, 11:21:03 AM
It is getting by the needle/seat so it would be trash or the float riding too high and not putting enough pressure on the needle. I doubt wear. You do need a filter between the tank & the carb.
There is a fine mesh screen insert in the filler hole of the tank, but no filter between the tank and the carb. My Honda-powered generator is the same way. Things are so tight on the splitter engine, that I can't really fit a filter in there - I'd have to run a hose out somewhere then another back in to the carb, with the filter dangling out in the open.
Snowmobiles used to do this year's ago and the fix was a viton.tip on the needle. What happens is the vibration either from running or riding down the road on a trailer expands the gas.like leaving a gas can out in the sun with the cap on tight.it has to go somewhere..this is why it has a shut off. Could also be the vent dose not work as it should. I have a small outboard that will do lt.the plastic fuel tank builds pressure in the sun.
If you carefully remove the strainer from the tank filler and peer inside, I think you'll find a fine mesh filter screen on the exit port.
My Honda 4 wheelers have a filter in the bottom of the tank, I would assume your little Honda does to, it HAS to have one somewhere. The screen in the filler, is just that a screen to get large particles, it does not double as a filter.
I don't care how respected your one man shop mechanic is, if it floods when the motor is shut off, it HAS either a float or needle and seat problem period, and he knows that it is not normal.
It is advised to shut off the fuel when carrying one down the road, but I never have with my 4 wheelers, my welders, my rotor tiller, nor my air compressors that stays in the service truck 24/7 365 days a year. They will not flood if everything is right.
Most Honda have a filter built right into the carb. It's right next to
the gas line input. It's the small bowl.
(https://forestryforum.com/gallery/albums/userpics/39553/Honda_carb.jpg?easyrotate_cache=1510012355)
It just sounds like crap to me,, sorry to say it like this but gee wiz, floats and needles open and close, depending on flow and (design) for further flow past, so,, figure it how it is, I would still stick with a Honda engine, I still believe it's as simple as faulty carbs,,
Quote from: Kbeitz on November 06, 2017, 06:53:23 PM
Most Honda have a filter built right into the carb. It's right next to
the gas line input. It's the small bowl.
(https://forestryforum.com/gallery/albums/userpics/39553/Honda_carb.jpg?easyrotate_cache=1510012355)
I thought that was just the shutoff switch. Didn;t realize there was a filter in there too.
Well if the engine turns over and just wont' start, then yea there may be a gas shortage,, I was thinking you had a locked up situation where the thing was just kinda kaput? fuel in the cylinder itself,, like many do without shutting off the gas flow,, I reckon you got it now,,,
Quote from: drobertson on November 06, 2017, 10:29:34 PM
Well if the engine turns over and just wont' start, then yea there may be a gas shortage,, I was thinking you had a locked up situation where the thing was just kinda kaput? fuel in the cylinder itself,, like many do without shutting off the gas flow,, I reckon you got it now,,,
One of the times, it was hydro-locked: the cylinder was full of liquid fuel. The other times is was fuel in the oil, and lots of it: When I opened the oil filler plug, the oil ran out of it like water, and lots of it.
Quote from: John Mc on November 06, 2017, 09:44:55 PM
Quote from: Kbeitz on November 06, 2017, 06:53:23 PM
Most Honda have a filter built right into the carb. It's right next to
the gas line input. It's the small bowl.
(https://forestryforum.com/gallery/albums/userpics/39553/Honda_carb.jpg?easyrotate_cache=1510012355)
I thought that was just the shutoff switch. Didn;t realize there was a filter in there too.
Not all have it. If it has the little screw on cap then it has a filter.