Carburetor Cleaning

I'm no carburetor expert and this is a very basic cleaning.

I start by removing the 2 phillips scres that hold the auto-enrichener on.

Once it is off, I make sure everything can move freely and clean it off with a little carb cleaner. Carb cleaner harms some plastic so you may want to just get the metal parts with it and wipe the rest.

I now remove the clamp and float bowl drain hose. Clean it off and be sure it is not cracked or torn. Replace if necessary.

Now I spray the carb with carb cleaner to get rid of a lot of the grease and gunk.

Remove the carb top. There is a gasket under it, inspect that and replace if it is damaged.

Take out the spring and throttle valve assembly as well.

Now I take out the 4 screws holding the float bowl in place.

My bowl has some buildup, so I spray some carb cleaner in the bowl and let it sit.

Now I take the pin out and remove the float.

Be careful not to lose the little float needle.

Remove the float bowl gasket and spray the carb out with carb cleaner.

Make sure the gasket looks healthy, replace if necessary.

I unscrewed the main jet to make sure it isn't clogged or dirty and sprayed it out. I then reinstalled it.

Holding jets up to a light will help you tell if it is clogged.

I then removed the idle speed screw and cleaned the screw and passage, then reinstalled. You may want to see how many turns it takes to get the idle screw all the way in, and write that down. When reinstalling, turn the screw all the way in then back it out that number of turns.

Now I do the same with the mixture screw.

Now I remove the clip that holds jet needle and it's clip in the throttle valve.

Clean all of these parts then reassemble. Be sure the M clip doesn't block the groove in the throttle valve when you put it back together.

Now I let all of this sit overnight so the carb cleaner can work it's magic on the bowl.

The carb cleaner has done it's work so I dump it out and wipe the bowl out.

I remove the drain screw and clean it and the opening with carb cleaner, then reinstall the screw.

Put the bowl gasket back in place, making sure it is properly seated.

Reinstall the float and float needle. Now is a good time to check float height by measuring from the bottom of the carb to the bottom of the float (which are both kinda the tops since it's held upside down). Vento wants a 12-14mm float height.

Reinstall the float bowl.

Now I put the throttle valve back in the carburetor. Notice there is a long groove and a small ramp on the throttle valve. The ramp is for your idle speed screw to contact, so aim int toward the idle speed scew when installing.

Put the spring back in.

Reinstall the carb top.

Put the auto-enrichener back on.

In my case, make sure the cap for the oil injection port is in good shape.

Reattach the float bowl drain hose and clamp.