I have a 1975 Merc 650 with a few problems... 1 identified, with 2-3 still lingering. Once started, it holds an idle fine, I can play in the 1000 - 2000 rpm range with no problem... once I hit 2000, I need to tap the choke every 200 - 300 RPMs until I reach 3000... then everything is fine from...