HONDA GXH50 cuting out after 10secs

[Atudge]

Honda gxh50

Okidoke so Ive got a gxh50 and its in great condition the carb is clean as a whistle as is the cylinder,fuel and sparkplug as you would expect for a pretty much new and unused motor

However upon starting the motor is runs for approx 5-15 seconds at idle speed only with choke on and max fuel before cutting out wont let me rev it without cutting out either.Now as theres a spark fuel and air I really cant seem to suus out what the score is with it.Ive tried checking the oil level thats fine and also disconnecting the oil sensor which can cause issues..still no joy.

So I have put it down to two options.

a) The idle speed of the motor needs adjusting(air2fuel ratio might be off,can this be adjusted?

b)Have I disconnected the oil sensor properly(is it as simple as disconnecting the yellow wire or is there any thing more technical I need to DO?



Your thoUghts are muchly appreciated.!!!thanks Al

 

[Old Bob]

try letting it warm up a little, don't apply full throttle with choke on

 

[Atudge]

Ive tried Bob,Ive tried to ever so gently feather the throttle to keep it running till it warms in the hope that it might find some rythm but cuts out.However I might try putting the motor in a very warm area(airing cupboard etc) to see if that helps before starting?

Could that be a possibility?

Appreciated Al

 

[Kline's Kustoms]

When you snap the throttle back does it want to cut out? I had the same problem but my GXH50 would idle. I had to clean out the jet in the carb. really good. Is this a new build? New tank and fuel line?

 

[HoughMade]

I know you said the carb was clean...but mine was too...until I ran it a bit.

Also, I had similar issues once when my home made gasket covered a small hole on the carb.

 

[Atudge]

Kline yee kind of you have to be ever so gentle with the throttle to mantain an idle before cutting out..Could it be something to do with the float in the carb.That looks clean and operates smoothly once I took the cup off tho hmmm.What method did you use to cleam the jets I think thats got to be worth trying?

Hough yee I see your point,I might investigate the carb more..got to be worth trying

Thanks Al

 

[Irish John]

Atudge, Are you sure the choke isn't on. If it's on it will behave like you describe until you switch it off. That is the first thing that springs to mind. The air/fuel screw comes at the correct setting on a Honda motor. You shouldn't have to adjust it but it is easy to adjust correctly. There might be a bit of gunk in the carby jet especially if you aren't using a good fuel filter. I clean the needle & seat using compressed air from a big hand pump with the nozzle held over the fuel line barb on the carby & that usually works well. I've always noticed dripping fuel from air filter box when gunk gets in needle/seat.
I think it's the choke or the needle/seat in that order.
You shouldn't need to touch the oil cut off switch on a Honda because they work fine leaving them as they are.
Is your throttle working perfectly?
Is the kill switch wired up correctly?
Are you using a Honda carb or a HS carb?
Good luck

 

[Quenton Guenther]

Hi Atudge,

Just a quick comment. Sounds like carburetor issues, however it is very IMPORTANT to use air to clean passages in a CAREFUL way.

If you use air under pressure with the float bowl attached you can crush or distort the float. I always remove the float bowl when using air to force any blockage from the carburetor passages.

The problem you describe sounds very much carburetor related, however make sure the tank's fuel flow is correct [open fuel shut-off with line disconnected to make sure].


Have fun,

 

[Stan4d]

I read somewhere that someone used the in tank filter in addition to an inline filter causing a similar problem. Turns out the cheep tank filter was the problem.

 

[Atudge]

Hello guys thanks for your help I agree it does sound carb related I have thorughly cleaned the carb in the most delicate of manners ensuring float is taken the very best of british care.

Irish john I have noticed fuel running down the face of the air filter box like you have mentioned in your post.Although im sure upon doing my sugical clean of the carb i would have released any gunk from the carby.Can you tell me the method in simple terms as to how you cleaned properly the needle and seat...and also where the air to fuel screw adjustment can be found just incase the engine has been tinkered with ....could possibly of been accidently upset along the way.Does seem to be running very very rich from the exchasut emmissions

Kindest of regards Al