1989 120 mercrusier 4 cyl

[garyaragon]

motor runs great when cold. after warm up gets sluggish. i mess with choke and air mix screw and get it to run ok but i have to keep messing with it to run ok. rebuilt carb, point, plugs, new fuel pump.i think its just adjustment.flap closed when cold. mix screw open 2 turns timing 8 deg. what else?

 

[Grub54891]

Re: 1989 120 mercrusier 4 cyl

Try changing the fuel filter.

 

[Oshkosh1]

Re: 1989 120 mercrusier 4 cyl

flap closed when cold. mix screw open 2 turns timing 8 deg. what else?

Is the "flap" open when warm?

2 turns seems a little "rich"...

Pull a plug and see what it looks/smells like after it's warmed up.

 

[Grub54891]

Re: 1989 120 mercrusier 4 cyl

That flap is the choke plate, It should be wide open after a couple minutes.If its not working it will run to rich.

 

[garyaragon]

Re: 1989 120 mercrusier 4 cyl

Is the "flap" open when warm?

2 turns seems a little "rich"...

Pull a plug and see what it looks/smells like after it's warmed up.

thanks for the tip