carb problems By jmiller5927 (Read 1,215 times)

[jmiller5927]

Bought a 02 moskito for $80 and it had not been run for a couple years. 2 stroke. Beat up pretty bad but figured I could make it run. Had to replace some parts and do a lot of cleaning but got it running. Heres the problem - It wont start without a shot of starter fluid then it runs OK for a while . After about 30 to 45 mins it wants to die at idle and then won't restart. Also runs a little sluggish at all times. Idle screw is out about 6 turns but anything less and the back wheel spins. Air fuel screw is all the way in but if I move it even a hair it will not run. Its a mikuni carb Im guessing about 18 mm. Has the throttle cable that connects directly to the slider. Im gonna take the carb off again today and reclean . Any suggestions would be appreciated. Thanx

[mthomas]

Two possible issues. Either the idle jet is plugged or the auto enricher is not working. Also, you should not use starting fluid as it will eat the plastic and rubber. Use a spray bottle with gas in it.

[jmiller5927]

There isnt a diapragm

[Alleyoop]

What kind of carb do you have? Does the Throttle Cable go down the center of the Carb or is the Throttle Cable attached to the Right side of the carb with a bracket?
Alleyoop

[Alleyoop]

Never mind, I read your first entry and you have the Slider type, throttle connects directly to the Slider with the needle.

Ok, so you have TWO adjustments on that Carb the Idle screw which is in the Center usually a bigger screw than the Fuel Screw which is smaller.
If you have to Turn OUT the Idle Screw 6 turns so it idles low enough and the Fuel screw all the way in, sounds like your getting to much fuel. Check the Float in the Carb it may be flooding it out and it appears your sucking in a lot of air from someplace as well.

Start it up and let it get warm, then get some Carb Cleaner and spary around the Carb area where it connects to the air fliter and intake and vacuum hoses and petcock. If the RPMS chanage you found a leak.
Alleyoop

[jmiller5927]

The needle valve on the float seats directly onto the brass guide. Is this correct or should there be some kind of seat in between?

[Bashan]

I've only worked on CV carbs but I would think the float mechanisms are essentially the same on both types of carbs. On my CV carbs there is a plastic ring embedded into float needle to help seal it as the float rises. However, if it was supposed to have that ring there would be a vestige of it left that you could see. If it's all metal then it was probably designed like that. Scoots that run a while and then die can mean a plugged vent cap. Loosen the gas cap a little and see if that makes a difference. It's probably not that but it's a no cost test and then you can take that off of the chart as a possible problem. RichRich

[jmiller5927]

Tried that - no luck. Im gonna test the auto choke today . When I got the bike the air intake was about 3/4 taped off so I think its getting too much air.

[jmiller5927]

Ok jammed 2 paperclips into the female end of the enricher plug and hooked it up to a battery charger --- works fine

[jmiller5927]

Ive tried just about everything I can think of . Idles really high and spins the tire . Once the choke engages it dies.

[sprocket]

If it dies when the choke engages then your idle jet may be plugged.

The enrichers usually open up a second passage for fuel and when that closes if the idle jet is plugged the engine will die...

Not certain your carb works the same.. but I would take it apart and physically clean the jets with wire. Also if you have an air/fuel screw remove that and make certain that you can get a wire through there too....

Probably to get it to run you have the throttle set high, so it is running off the main jet, that is why it is at such a high RPM...