Carb / Fuel / Mixture / Choke

[Ray LeCheminant]

Sorry for the mixed bag of statement in the thread.

B2 WC will not run. Starts with the aid of Engine Start.

Have to run on choke, then blip it to remove choke, fuel then starves and starts to run lean , have to turn on choke again to keep running , loads up , so blip the throttle again, and the cycle repeats?


Carb has been cleaned out

Need and seat look ok

Appears to be getting plenty of fuel (but no screw on bowl to be sure)

Fuel line full of gas, filter on right way - sometimes looks like airlock in line

Questions:


Do I have a jetting issue

Can an air leak cause this phenomena

Hope you guys have some ideas please....

Ray

[FJRider]

More like SPARK PLUG problem, Maybe give plug a clean...check GAP. Do you know what is the correct gap ??? How OLD is the plug ??? Even NEW plugs fail ...Such is the 2 stroke...
Stop air getting in to the fuel line... runs on petrol not air.

[BigAl]

Hey Ray, you definitely don't want air in your fuel line & could try removing filter to test. btw is it a std chinese filter?
An air leak causes the engine to rev up rather than die, I believe.
Also since you've rebuilt your motor and increased capacity you probably should rejet the carb as I presume you are using the std 14mm original carb.
I would get hold of Bret and put it on his dyno together with his mixture sensor.
cheers.

[Ray LeCheminant]

More like SPARK PLUG problem, Maybe give plug a clean...check GAP. Do you know what is the correct gap ??? How OLD is the plug ??? Even NEW plugs fail ...Such is the 2 stroke...
Stop air getting in to the fuel line... runs on petrol not air.

Hi FJRider - tried 2 plugs.....just spoke to the guy I got the engine rebuild kit from....is suggesting a possible air leak, so going to concentrate on getting it to idle and spray Engine Start around the intake manifold and see if there is an induction leak. Apparently if there is an air leak, the engine start should make the engine revs increase. Or.....it could be a problem with the carb

[Ray LeCheminant]

Hey Ray, you definitely don't want air in your fuel line & could try removing filter to test. btw is it a std chinese filter?
An air leak causes the engine to rev up rather than die, I believe.
Also since you've rebuilt your motor and increased capacity you probably should rejet the carb as I presume you are using the std 14mm original carb.
I would get hold of Bret and put it on his dyno together with his mixture sensor.
cheers.

S O L V E D

Running like a dream - and kicking myself!!!

Spent all day chasing an intake leak, surely that could have been the only problem. Cracked the cases open again, remade the gasket, put it all back together with precision....same problem....

Only way I could run it was use the choke to control the revs...then I notice something...

with choke off, every time I opened the throttle, it would run lean, BUT fire fuel out the carb....yes...

The last person who owned it put the emulsion tube backwards, so was firing the fule towards the aircleaner - DOH...quick removal of carb, 180 degree twist of the tube, holes now towards the intact

WALLAH - Working....now onto my next problem - NEW THREAD!!

Ray