Gas problem

[blocky54]

Hey guys , I’ve been trying to fix my 49cc aprilia sonic whenever i try to kickstart it won’t start , I poured a bit of gas into the carb and it start after many trials but won’t stay on unless I open up the throttle , when I pull off the gas hose that goes in the carb and kickstart there’s no gas coming out . Pls help

[geoffh]

It sounds like your carb needs a good clean,strip it down and check all the passage ways are clear,use wire,drinking straws,sonic screwdriver if you have one there are two hoses to your carb the large one is for fuel the small one for vacume,suck on the small one and fuel should run out of the large one.

Geoff

[blocky54]

Thanks for ur reply Geoff, I did try that and the fuel does run when I suck on the vacuum hose , I noticed that when I kickstart the fuel doesn’t flow like when I apply suction I did clean the carburetor many times

[geoffh]

Try a new plug,clean the air filter,recheck the pilot jet is clear have you checked the cold start system is working,use the directory icon on this page to find Brent,s no start check list,keep asking till its sorted.

Geoff

[blocky54]

I got a new plug , same thing , I should mention that she doesn’t have an air filter nor an auto enricher , she only starts when I pour gas into the carb or the combustion chamber
Here’s a pic my carb
ibb.co/R2ZvxcS
ibb.co/K58Vr8z
ibb.co/J5g6byw

[geoffh]

You will need to have airbox assy fitted if you want this to start properly,what year is your scoot,a quick look at apriila parts catalogue suggest the air box is similar to the cheap and cheerful minarelli box available for$20 ish.looking at your pictures that carb has been through the mill,the jets are varnished over new ones or try boiling them in vinegar and water.y

Geoff

[blocky54]

Alright , i will get an airbox and newer jets tomorrow , will let u know asap , rly appreciate ur helped

[wiscootsin]

Without the airbox your carb likely doesn't get the right vacuum pressure to start the vacuum petcock sending gas into the carb. I've had that happen with an airbox on too but wasn't restricting airflow enough.

Another option is to get rid of the vacuum petcock and put a shutoff valve instead. Let it gravity feed.

I hook a fuel line from the carb to an open 30ml syringe while testing to isolate problems.