Sunl 70 that will not stay running unless the choke is pulled slightly out. Even after a good 5 minutes of warm-up, if you turn the choke off (push in on choke cable) it will stall right out. Tried to adjust idle screw (phillips one) and the screw does not or at least minimaly changes idle speed. Should I take the carb off and dissassemble it and give it a good cleaning??? Also......I hve also noticed that the throttle cable has an adjustment about 8" from the thumb control. the jam nut had loosened up and I know that this adjustment is out as well. Any advice will be helpful. THANKS!

 

will it idle if you push the throtle a little or does it still die ?
how many hours on it ?
sound like it is running to lean could be just an adjustment or something caught in the jet I would try to adjust the air mixture screw before pulling it off

also can be a vacum leak if you have some starting fluid spray around carb if it idle's up you have craked intake or something if it stays the same you have no leaks

be very carful with starting fluid it likes to go boooooom!!!!!!!!!!!!

 

Once quad is running, you can push throttle it revs up but once released it it take quite a few seconds to to come back down.

I don't think their is much more than 20 or so hours on it.

mixture screw seems not to make any difference where it is positioned. I have had it all the way in and even had ot removed with no change!

I'll check for leak tomorrow and report my findings

Thanks for the input!

 

The Jam nut thread area on the cable just down from the thumb throttle is used to make the outer case of the cable longer or shorter than the inner wire. You can use this to set the idle. if this came loose and the cable vibrated shorter you can do every thing in the book and it won't idle right.
1.Set your Air/gas adjust screw to about 1 turns,
2. lengthing the cable till it low idles, let it warm up,
3. turn the Air/gas adjust screw out 1/4 turn wait 15 sec.
4. if idle speed changes Repeat #3
5. When idle speed dosn't change then set it back 1/4 turn.
6. If the idle is to high now shorten the cable to a good idle spot and tighten the lock nut.

This is for adjusting cable length and and the air/ gas screw that feeds the carb at idle.
If your fuel filter is dirty (or missing) you may have a speck of dirt in the slow jet. If you want
a good sight with info on CV "constant velocity" carbs. go to nightrider.com Carburetor and Fuel System Troubleshooting Guide

Text

Good Luck Nitrox

 

Thanks again for the input. I checked for a cracked intake as well as air leaks and found none (starting fluid test). I'm going to remove the carb tonight and clean it all out!

 

FNA, The fact that giving it gas and let off kicks the idle way up just screams to me of a lean condition somewhere. Make sure the exhaust pipe is tight to the head and that junction doesn't leak. Maybe go over it again and check the intake for a crack, loose connection, or other leak. If that doesn't find it, check the carb, adjust the air screw and/or pilot jet as needed. Good luck.

 

I took the carb off this evening. Carefully took it completely apart. I could see an area in the fuel/float bowl where something (gel pack?) may have been. A ton of residue on the bottom of the bowl! Pulled all jets and needles out. flushed everything with carb cleaner. Reassembled the carb and installed it back on the quad. Replaced the hardened fuel line with REAL fuel line (SUGGEST THIS BE DONE BY ALL MINI-QUAD OWNERS!). The quad fired right up and was able to adjust idle with idle screw. Performed basic carb adjustments and quad runs like a top!!!!

Anyone that has running problems I suggest yanking the carb and giving a complete breakdown and cleaning!!!

Thanks for all input!