Issues with idle jet on Honda BF8 8HP

[isaksp00]

My circa 1991 Honda 8HP periodically has idle problems. It starts fine with choke, and seems to idle OK, but if I put it in gear and then try to accelerate (even gradually) it stalls. Removing the idle jet, the one on top of the carb that can be removed without disassembling, and cleaning with a fine plastic "wire" and some carb spray smooths it out. I gather these are very susceptible to the tiniest particles.

This is annoying (and one of these days I'm bound to drop the jet overboard), and if I don't realize it in advance, makes for tough maneuvering into my slip (if it stalls out). I do run the carb dry after every use by disconnecting the fuel line and letting it run until it stops. It has a fairly new Honda fuel filter.

Has anyone figured this out or found a solution or improvement?

Thanks, Peter

 

[ondarvr]

You need to clean the entire carb and put a good filter in place. They are very sensitive to even the smallest bits of junk, and without knowing exactly what the stock filter looks like I can't say if it's a good one or not. Running it dry doesn't drain the carb, it only lowers the fuel level in the bowl. The fuel lines will dergade over time and small peices can get lodged in the carb, the filter can only catch what's upstream of it in the fuel system, there could still be bad fuel line downsteam of the filter.

 

[isaksp00]

Thanks for the reply. The fuel lines are fairly new - maybe 2 yrs, so unless they degrade very quickly, I would hope the line downstream from the filter is not the root cause. I did not realize there were possibly better quality filters than what you get from a Honda supplier. Any recommendations on what would be a good quality filter suitable for an 8HP? Like brand or online supplier, or type?

 

[MattFL]

Check if that motor has a filter under the hood. If it does, replace it with a Honda brand filter. Cleaning out the carb isn't a bad idea, there might be small particles in the bowl. I personally wouldn't run the fuel out unless it's going to be a very long time before you use it again. To get it all out you actually have to remove the bowl drain to empty the bowl, then try to start it to empty the circuits in the carb. Use stabil in every tank and fresh fuel.

 

[isaksp00]

Matt, thanks. It does have a filter under the hood, and I did buy it from a Honda parts supplier (Honda brand). It is a white colored drum-shaped filter. It is about 2 yrs old (I have a sailboat, so the 1.5 seasons use is not many hours and not much fuel going through it - maybe say 4 or 5 gals max). I have no idea if that kind of stock filter is any worse than other types I could buy. The grey colored fuel hose material was also bought from a Honda supplier.

I also add StaBil at each fueling.

I could (but I don't) remove the carb bowl drain screw after each use, as it can be accessed without removing the carb, and more fuel would be removed (though I'd risk dropping that small screw, and also drip some gas into the lake).

 

[ondarvr]

There were issues with some types of gray fuel line, and sitting around is hard on some of these small 4 strokes, any gunk that forms in the carb while not being used tends to cause problems.

 

[Sea Rider]

That carb probably needs to be completely disassembled, rubber and plastic parts removed, soak in carb dip for some hours rest, rinse with generic carb spray every single intrior spot, dry and assemble back. Use fresh fuel.

Is your fuel tank and small mesh filter located under pick up fuel tube in immaculate clean conditions ? It's a good thing to consume fuel leftovers on carb bowl, E fuels detereorates, elonges faster thin rubber parts as o'rings, fuel pump diaphragams faster compared to non E fuels if sitting for time periods. If you want to consume the most out of bowl, when engine is about to die, pull choque in/out and throttle, repeat procedure untill engine doesn't fire up any more.

Happy Boating

 

[MattFL]

I've always had the best luck buying oem parts. That goes for cars, mowers, boats, motorcycles, etc.. Especially with name brands like Honda, Yamaha, etc.. The oem parts tend to be solid. You don't have to remove the drain screw all the way, just loosen it and fuel will flow either around the screw out out the drain port.

 

[isaksp00]

Thanks for all the replies. I think I am just going to have to live with this by removing and cleaning that jet every so often, if it acts up. I may buy a spare, just in case it drops.

The entire carb was dipped for about 4 hrs not that long ago (I think start of last summer), and after I clean the removable jet, it runs fine - so I doubt it is an issue with the other orifices. I guess I could try draining by opening the screw. I typically leave the boat unused for about a week, maybe 2, in between each draining. Since I have the OEM filter, I guess there's nothing to be gained by its replacement. And I had washed out (power washer) the fuel tank at end of last season, so it ought to be OK.

 

[MattFL]

If it sits in the hot sun, try to cover it with shade somehow. The thea heat can dry the gas and accelerate carb clogging.