My son's 90cc ATV with a PZ-21 carb won't run without choke. I put on a new carb a year and a half ago. Does it likely just need a new jet from a rebuilt kit?

 

have you tried cleaning it first?

 

I've put Seafoam in the gas and also sprayed carb cleaner into the carb. I have not removed the jet and tried to clean it. I'll have to try that but haven't had good luck with cleaning them in the past. Thought it might be more worthwhile to just replace the jet.

 

so the carb ran great for 18 months and now it's acting up?

 

Pretty much. It's been getting steadily worse over the last few months.

 

well if it ran good then performance deteriorated, i'm unsure. surely the jet is the right one for your elevation, right? i mean, the choke richens the mix, so unless you have a vacuum leak, it'd be a jet issue, right? quick test, get it running, spray ether/starting fluid around intake boot and see if she revs up.

 

Couldn't the jet just getting more and more clogged?

 

if the jet was getting more and more clogged, you couldn't rev it up, it would start bogging down with more throttle.