I hate carbs!!!

[Ottoman711]

Anyone have know how on how to adjust dual carbs on a four cylinder two stroke? Anytime I touch carbs it gets worse!!! I can't find any DIY videos. Boat only ran in warm up mode and now it runs like complete sh** after I played with adjustments...

 

[Neutron]

What is this on, what engine.
Mikuni or Keihin?

 

[Ottoman711]

Mercury sport jet 120.

 

[RedBarron55]

Google force link and sync for carbs, timing and complete set up.
https://forums.iboats.com/forum/eng...ler-outboards/616464-carb-and-timing-tutorial

 

[Neutron]

Sounds like the pilot jets are clogged or restricted. Take the bowls off and clean out the jets. The pilot jet is the one with the smallest hole in it. Sometimes you have to push a very thin solid wire through it like a thin paperclip

 

[Ottoman711]

I feel I've adjusted it completely wrong now but I will try cleaning the carbs altho I never have luck

 

[itsdgm]

Anyone have know how on how to adjust dual carbs on a four cylinder two stroke? Anytime I touch carbs it gets worse!!! I can't find any DIY videos. Boat only ran in warm up mode and now it runs like complete sh** after I played with adjustments...

That’s a bummer. I’ve never been good at adjusting multiple carb/barrel set ups. Fwiw, one thing that i learned early on was before i made any adjustments to measure each jet setting before i messed with it. I would count the turns on each jet by screwing them in and counting it at 1/2, 1, 1.5 etc until it bottoms out. That way i could always return it to the original settings and try again if i made it worse.

I do believe that there’s a gauge that sits on top of the intake and measures the vacuum. The you can adjust each one to sync them up. But like i said, I’ve never done it personally. I’ve only discussed it with an auto mechanic about 30 years ago so my memory could be off here

 

[Neutron]

Does it have fuel mixture screws or air mixture screws.
If the adjuster screw is closer to the airbox its an air screw and if closer to the engine its a fuel screw

 

[Ottoman711]

There are only two screws (one each carb) on the actual carbs. The only thing I messed with was linkage screws. One of them being the butterly adjuster to make the top and bottom match when opening and closing. All the linkage adjusters im talking about are the ones that act like a tie rod end in a vehicle. Spin the rod to adjust and a locking nut.

 

[Neutron]

To set/sinc the carbs you will need a vacuum sinc gauge set
Otherwise you will need to adjust each carb to get the throttle plate to the just closed adjustment then crack it a hair open without the linkage on. Then set the connecting linkage to the carbs making sure it is not moving the individual adjustments.
Post a few pics of the setup and it might help

 

[Beachbummer]

On my 717 seadoo Engines I would just buy new from Mikuni. Could never set them right. Also started using spin on fuel filter/water separators and they lasted way longer...maybe 4-5 years?

 

[RedBarron55]

Follow the instructions in the linked reference and you can also google for a video for the Force setup.
The throttle plates must be closed completely and the setup like the instructions say.