1997+ Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-826148R2, Page 102Get this manual
8With throttle at idle position, turn idle spe ed screw clockwise "INuntil gap of 0.005 in- 0.040 in(0.13 mm1.02 mm) is achieved betwe en throttle cam and cam followerThis will open the throttle shutter enough to ke ep the engine running ne ar idle spe ed after starting0.005 in 0.040 in(o.13 mm1.02 mm)
WARNING
Keep clear of propeller while cranking and running the outboard motor10C onnect the fuel line to the engine and electrical harness on electric engines11With the outboard in the water, start engine, check tell-tale, and allow to warm up12Adjust idle spe ed screw in "F RWAge ar to specification; (750 50 rpm) 13C heck the idle timing and maximum spark advance(If not within specifications, adjustment will be required)aIdle timing: degre es B.T.DC bMaximum spark advance: (2228 egre es, eference only)O ne (1) Turn clockwise after contacting throttle plateTIMING AND MAXIMUM SPARK ADVANCE ADJUSTMENTSMECHANICAL SPARK ADVANCE MODELS