Initial Adjustment

Completely close (turn clockwise) both adjusting

A Fuel inlet screen B Main fuel supply channel C Inlet needle and seat D Float valve plug screw F Float G Throttle disc H Idle mixture discharge ports J Idle mixture channel K Bowl air vent L Idle tube and plug M Idle tube fuel orifice N Idle tube gasket O Idle adjustment screw P Idle air bleed channels Q Choke disc R Venturi S Bowl gasket T Main nozzle adjusting screw

U Main nozzle air bleed tube

V Fuel bowl drain screw W Main nozzle orifice

X Main nozzle channel plug

Y Main nozzle

Z Main nozzle sump screws until snugly seated without forcing, then open them up to the normal setting as follows:

Main mixture (1) - 1-1/2 turns open Idle mixture (2) - 3/4 turn open

Above normal settings are approximate and will vary for individual engines and operating conditions.

Closed throttle, idling speed of engine is adjusted with idle speed stop screw (3). Before making this adjustment, be sure throttle control wire is so adjusted that throttle fully closes with outward handle bar grip movement; engine should be at normal operating temperature.

Turn screw (3) to the right for faster idling speed; to the left for slower idling.

Readjusting idling speed may change idling mixture slightly, therefore after making this adjustment, it may be found necessary to make minor readjustment of adjusting screw (1). Final adjustment of the main mixture may be made after a performance check under road load conditions.

DISASSEMBLING CARBURETOR (Fig. 3F-14)

Disconnect throttle and choke wires from the carburetor connection. Shut off fuel supply and remove the hose from the carburetor nipple. Remove carburetor from the intake manifold.

Remove carburetor to manifold mounting gasket (1), gasoline line elbow (1A) and inlet screen (IB). Remove main mixture screw (2), packing nut (3), packing (4), gland (5), and main packing screw gland gasket (6). Remove 4 bowl screws and lockwashers (7). Remove bowl (8), and gasket (9) from carburetor body. Screw out float lever pin-screw (10) securing float (11) to bowl; with a heavy blade screwdriver, remove large float bowl plug screw (12). Using tool Part No. 94816-62 and screwdriver, remove inlet needle valve (13), spring (14), seat (15) and gasket 6) from bowl. Remove small float bowl plug screw

Free idle mixture screw (18), and idle mixture screw spring (19). Remove carburetor idle tube (20) and gasket (21). Remove main nozzle channel plug screw (22). Remove main nozzle (23).

The throttle and choke shaft need not be removed unless carburetor has been excessively used and examination discloses undue wear of throttle shaft and its bearings. See "Cleaning, Inspection, and Repair."

If it is necessary to remove throttle shaft and lever (26 or 26A), remove idle speed screw (24) and spring (25). Remove throttle stop lever retaining screws (27), lockwashers (28), and throttle stop lever (29) (if used). Remove throttle shaft friction spring (30). Remove throttle stop (31) and lockwasher (32). Remove throttle shaft retainer clip (33), and throttle shaft seal (34). Remove throttle disc (36) by removing 2 disc screws and lockwashers (37). Pull out throttle shaft making sure shaft seals and bushings are not lost in removal of shaft.

1. Main mixture 3.

adjusting screw 4.

2. Idle mixture adjusting screw 5.

Idle speed stop screw Throttle control lever Choke lever

Figure 3F-13. Carburetor Adjustment ers (40). Remove choke shaft retainer clip screw (41), lockwasher (42), and retaining clip (43). Pull choke shaft out of carburetor body, making sure choke shaft spring (44) is not lost in removal of shaft.

CLEANING, INSPECTION AND REPAIR

Soak all parts except gaskets in Gunk Hydro-Seal. Thoroughly wash away all grit and sediment, then blow dry with compressed air. Blow air through all internal fuel and air bleed channels.

If necessary, remove welch plug (45), and check idle mixture discharge ports (Fig. 3F-12) to be certain they are not wholly or partially plugged. Then tightly install new welch plug.

Wash and blow out main nozzle (23) and idle tube (20). Carefully inspect main mixture screw (2), idle mixture screw (18), inlet needle valve (13), valve spring (14), valve seat (15), and valve gasket (16). Especially note condition of inlet needle; a badly grooved or worn pointed surface will prevent correct fuel level. Replace as needed. Inspect float for leakage and replace if necessary.

If it is necessary to remove choke shaft and lever (38), remove choke disc (39), screws and lockwash-

Always renew gaskets and main m ing (4) when reassembling.

screw pack-

0 0

Post a comment