Subaru Robin Power Products EY33-2, EY44-2 manual Pilot System, Disassembly and Reassembly

9-1-2 PILOT SYSTEM

This pilot system feeds fuel to engine during idle and low speed operation.

The fuel fed through main jet (MI) is measured b y pilot jet (PJ), mixed with air measured by pilot air jet (PAJ), regulated by pilot screw, and then fedto engine through pilot outlet (PO) and bypass (BP).

The fuel is mainly fed from pilot outlet(PO) during idling.

9-1-3 MAIN SYSTEM

This system feeds fuel to engine during medium andhigh-speed operation.

The air measured by main air jet (MAJ) is mixed into fuel through bleed holesof main nozzle (MN) and discharged t o main bore (MB) as atomized fuel where it is mixed with intake air through air cleaner to become an optimum air-fuel mixutre to b e supplied to engine.

9-1-4 CHOKESYSTEM

Thechokesystem serves tofacilitatestart-upincoldseason.Whenengine is crankedwithchoke (C) closed,thenegative pressure t o main nozzle (MN) increases to introduce fuel inlarge quantities to make start-up easy.

9-2DISASSEMBLY and REASSEMBLY
Besides mechanical,failures,mosttroublesarecausedby
incorrect mixing ratio.
Themostcommoncauses		ofsuchincorrect	fuel-air mix-	5
turesare clogged jets,restrictedairandfuel passages, and
				7
variationsinfuel	level.	Inordertoobtainthefull
performance of carburetor, it is necessary tokeepair				6
cleanerandcarburetorclean		so that air	andfuelflow	1
without any restriction.
				7
Observefollowingdisassemblyandreassemblyprocedures.
				8
(See Fig. 9-2)				25
9-2-1THROTTLE	SYSTEM			24

1)RemovePhilipsscrew(11 ), removethrottle valve ( 1 5 ) ,

and then pull out throttle shaft (16).

2 ) Detachspring (7) by unscrewingthrottlestopscrew

(8).

9-2-2 CHOKESYSTEM

1 ) UnscrewPhilipsscrew(1l),removechoke valve (9), pull out choke shaft ( I O ) , and then remove choke ball (1 2) and choke spring( 1 3) .

2 ) Whenreassembiing choke shaft, placethenotchof choke valve on main air jet side.

Fig. 9-2

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