ADJUSTMENTS
INITIAL CHOKE VALVE PULLDOWN ADJUSTMENT
- Remove choke coil housing assembly
- Open throttle about half way
- Place fast idle screw on high step of fast idle cam
- Bend a .036" diameter wire gauge at a 90* angle about 1/8" from its end
- Insert bent end of gauge between choke piston slot and upper edge of right hand slot in choke housing
- Turn choke lever counter-clockwise until gauge is held snugly in piston slot. Hold lever lightly to maintain gauge position
- Move top of choke rod away from carburetor and move bottom of choke rod towards carburetor to remove slack from linkage
- Insert gauge of proper size between lower edge of choke valve and air horn wall (at center of carburetor)
- Adjust by turning hex head lock screw on choke valve shaft clockwise three full turns
CAUTION: lock screw has left hand threads
- Pry choke lever from shaft to loosen
- Check that choke lever rotates freely on shaft
- Place correct size gauge between lower edge of choke valve and air horn wall
- Apply light closing pressure on choke valve
- Tighten hex head screw on choke shaft
- Using a .036" gauge in vacuum slot (above top of piston), hold piston in full down position
- Rotate thermostatic spring lever back and forth to check for binding
- Install gasket and choke coil housing assembly
DELAYED CHOKE PULLDOWN ADJUSTMENT
NOTE: Vacuum operated delayed choke pulldown diaphragm should open choke to wider setting about 6 to 18 seconds after engine startup
- Place fast idle screw on fast idle cam
- Note position of index marks on choke coil housing
- Loosen choke retaining screws and rotate cap 90* in rich (closing) direction
- Disconnect vacuum hose from port on delayed choke pulldown diaphragm assembly
- Remove filter cap and place tape over purge bleed hole in diaphragm housing
- Connect outside vacuum source of at least 14-18 in Hg to port
- Insert gauge or drill bit of correct size between lower edge of choke valve and air horn wall at center
- Adjust by turning stop screw on delayed choke pulldown diaphragm
- Remove vacuum source, reconnect hose to port and reset choke cap to correct setting
NOTE: Remember to remove tape from purge bleed hole
DECHOKE CLEARANCE ADJUSTMENT
- Move throttle to wide open position and hold
- Turn choke valve towards closed position until pawl onf ast idle speed lever touches fast idle cam
- Measure clearance between lower edge of choke valve and air horn wall
- Adjust by bending pawl on fast idle speed lever FORWARD to INCREASE or BACKWARD to DECREASE clearance
AUTOMATIC CHOKE ADJUSTMENT
- Loosen choke cover retaining screws
- Rotate choke cover to align index mark on cover with correct mark on housing
- Tighten retaining screws
