1975 Evinrude 40 HP Outboards Service Manual, PN 5093, Page 26Get this manual
CARBURETOR ADJUSTMENTS THROTTLE CAM ADJUSTMENT aIf throttle does not close, either the throttle return spring is too weak and should be replaced, or the throttle or linkage is bindingbRemove ring gear guard (Electric Start Model)To check throttle adjustment, advance throttle control so that projection on intake manifold is centered between two marks on throttle camSee Figure 3-19At this point, the throttle valve should be closed, the cam follower roller must touch cam If notadjust as follows: cAdvanc throttle control so that projection on intake manifold is centered between two marks on throttle camSee Figure 3-19dLoosen throttle arm clamp screwMake sure that throttle valve is in closed position, the cam follower roller must touch cam, and tighten screwSee Figure 3-20eThrottle valve should just begin to open after first mark on cam passes projection on intake manifold as throttle is advancedfTo adjust throttle to conserve fuel at cruising speed, move armature base by hand to full spark advance, without touching throttle controlAdjust control rod collar for 1 32 inch clearance from pivot pinSee insert, Figure 3-20Figure 3-20Adjusting Throttle Linkage