Go Kart keep cutting out please help

Hello

Just found this forum great place

Any help on this problem would be very much appreciated

I just brought a little 49cc 2 stroke go kart for my kids to have a little fun on i brought it 2nd hand but seems pretty new when i went to pick it up the guy showed me it all working and even tried it in front of me and went up and down the road on it

Brought it back home had a little go on it for around 5 minutes worked no problem, tried it 10 minutes later now it keeps cutting out

It seems to start OK but as soon as you pull the throttle back it just cuts the engine out

Also when you pull the throttle back it doesn’t spring back like i thought it would is that suppose to do that?

Spent about 2 hours on it today taking it apart but couldn’t see what the problem was i was going to try and take the carburetor apart but i don’t see where this jet is to clean out if that's even the problem

I have also made sure that there is air getting into the tank but again made no difference


Once again thank you for any help you can offer

 

you are using a oil/gas mix right?

the throttle should spring back
what type carb? throttle line goes in from the top or on the side?

 

Hello

Thank you for the reply

Yes it has been mixed correctly

The throttle just seems to keep sticking

I am not sure if it comes in from the top or the side as i am not familiar with these karts

I have taken some pictures which are below hopefully you will be able to tell me a bit more from these

Thank you again for your time and help




http://img153.imageshack.us/img153/8291/83471939tp8.jpg

http://img155.imageshack.us/img155/8148/50585608hr3.jpg

http://img155.imageshack.us/img155/5088/12524434lv1.jpg

http://img294.imageshack.us/img294/8899/72085170ii5.jpg

http://img133.imageshack.us/img133/6853/68620777hw8.jpg

 

there should be a spring on the throttle as well as on the carb. your last picture shows the carb spring. if it doesnt return to idle when you let off there is a cable problem. maybe try some wd40 down the cable line if there is no obvious kinks or unraveling on the cable. is there an air filter? these little carbs are sensitive to the air flow and also to any dirt. The odds are that motor is a 32 or 36cc engine, not a true 49cc. important when you go to buy parts. also the little bubble on the carb needs to be in good shape, no air leaks/gas drips. put it back together and use some carb clean, and get the cable unstuck. do the throttle from the carb with no load(wheels off the ground) and see if it works. make sure the kill switch isnt being activated when you give it throttle. you can unplug the kill switch for trial purposes.

 

The two springs on the throttle are rather important especially if you have a small child driving the cart. A child may not think fast enough to use the kills switch with a runaway engine. The spring right at the carb. is important since you want the engine to go to idle even if the throttle cable breaks.

I know this may seem too obvious but did the idle screw back out allowing the throttle to totally close when you took your foot off the gas (killing the engine)?