1988 Yamaha 130EXTG. Idles creeps up too high when warm.

[jeff111]

Engine starts eagerly. When cold, idles high (as normal) then drops. Once warm though, it creeps up to around 1500 RPM. If I choke it it drops to around 800 or so for a minute but creeps back up again. Haven't really run it yet this season, just started it with muffs. Any ideas? Thanks!

 

[jeffersondodson561]

Re: 1988 Yamaha 130EXTG. Idles creeps up too high when warm.

Sounds like you need to verify timing and carb syncronization. Remember you have no back pressure while on the flushette so this could effect rpms by as much as a 100 once in the water. Might want to do a cylinder drop test first though being that your rpms are already this high this will eliminate the need for a spark test if all cylinders drop in rpms. If you go to Lowes and get fuse pullers to pull the spark plug off each cylinder while it is running, if you hear a drop in rpm means that you have spark and combustion (does not mean fuel air mixture is right) at 1500 rpms an untrained ear will be able to hear the drop in rpm. If you don't hear a drop means you don't have spark or adaquate fuel air mixture. The difference in temperature vs. running condition is probably do to fuel atomization, being atomized better once warm.