Hello,

I Bought a used brison 3.2 few months ago without the choke on it. Then I was just using my thumb to prime it. Starting was a pain as it was shutting down after few seconds. The problem was clearly a lack of fuel after 2~3 seconds. Even when warm was difficult to start.
I look everywhere for two months, rebuild the carb, messing up with the low & high end, looking at the tank, Checking ignition and battery and look for air leak. Never found anything until I decide to buy a new Carb on ebay for 10 $ (Walbro WT 76a). I put the new carb and was having the same starting problem. Then I decide to use the choke on the new one and then it was day and night. Now it does start like a charm.
I still try to understand!!! The only thing I have in mind is that with the choke usage is getting rid of some air bubble on the top of the lever-diaphragm. Did some of you have an explanation of this problem?

Thanks.