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12V802 190CC b & s engine carb-primer problem

#1

N

Narko

Engine runs fine on external fuel (propane) but won't stay running on its own once propane feed is removed. Initial problem was gas "peeing" out of hole on primer bulb hole. Cleaned carb and tested float valve initially with air pressure and then with gasoline with a tube and small funnel held gas ok. Apparently is not carb is not supplying gas to engine. Pushing prime bulb does nothing either. Any ideas? Cud the float valve be stuck? Thanks.

Also what is a tag ? (wanted below) A name given a thread?


#2

I

ILENGINE

did you also make sure the jet in the bowl nut was clean. Also it is not unusual for the air filter mounting surface were it contacts carb to warp preventing sealing, which will prevent the primer from working.


#3

N

Narko

did you also make sure the jet in the bowl nut was clean. Also it is not unusual for the air filter mounting surface were it contacts carb to warp preventing sealing, which will prevent the primer from working.

Thanks ILENGINE,

Removed the carb again. The holes in the bowl nut are clean and the passage to the venturi is clean. Put tiny tube in carb prime hole and can blow (by mouth) air thru.
The carb-to-engine O-ring fit does not feel right. The gasket between the primer assembly and the carb needs to be replaced. The primer assembly can hold pressure when outlet to carb is blocked. There is no problem with primer-to-carb surface warping. Other than correcting the indicated issues is to squirt carb cleaner thru all openings and if that does not work get a new carb from ebay for $10 ?


#4

N

Narko

Bench tested carb with air gun blowing thru venturi got mist so figured carb is ok. Changed out carb-to-engine O-ring. Seems will run on gasoline now. Next to make new primer assembly-to-carb gasket probably from innertube to see if can get primer to work.


#5

N

Narko

For the primer assembly-carb junction made a new gasket out of that mounting foam tape which is sticky on both sides. Had to be careful as channel for air from primer bulb has to travel about 5/8" within 1/8 inch of edge. Lawnmower now starts and runs fine.


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