engine problems

[bkrider113]

I just got a very basic beginner kart for free from a friend. It has a briggs and stratton 3.5hp. Engine will only start with light throttle or choke but will not continue to ilde choked. Once you apply throttle for a few seconds it will idle fine. My main problem is once hard throttle is applied and you let off completly the engine dies.

 

[brendonv]

play around with the mixture screw, little screw under the air filter, it probably needs to be turned in a lot. Also clean ur air filter. First before messing with the mixture take the air filter off and run it. If it runs fine then u gotta clean ur air filter. If its still bad u gotta adjust ur mixture screw. Mixture screw should be like 2 turns out or around there. Mine was the same as urs and the mixture was like 2 turns out to much, it wouldnt go over about half throttle, it would just die. Now it revs really high. Just run ur engine and turn it till it sounds good, then put it on full throttle and adjust to how high u want it to rev. After that u can adjust the idle speed with the little screw on the throttle butterfly.

 

[Kaptain Krunch]

play around with the mixture screw, little screw under the air filter, it probably needs to be turned in a lot.

The mixture screw is normally on the side of the carb, saying its under the airfilter may confuse some people (took me a minute haha). i suggest cleaning the carb really well, and then cleaning the airfilter really well. Once the carb is cleaned, turn the mixture needle in all the way, then back it off 1.5 turns, that should get you started, once its running adjust the screw till it runs good.

 

[bkrider113]

ok well after tinkering with the screw today then engine studders now when throttle is applied no matter what position the screw is in. I think i wasnt waiting long enough between tuning and burning the excess fuel from the previous tune. Once again little to no experience with carbs but do you guys agree, and any additional info would be great. I'd tinker with it now but I just got out of work and want feedback for tomorro morning.......... Is turning the screw to the right richening or leaning the mixture.....leaning right????