Zama Carburetor

[Dennisfly]

I have a leaf blower with Zama diaphram carburetor that won't run. The fuel line broke after the blower sat unused for about 3 months. I replaced the line and filter but the it won't start using conventional procedures. If I pump the primer bulb repeatedly about 30 times, it will start and run 2 or 3 seconds and then quit. If I manually squirt fuel in the carburetor, it will run 2 or 3 seconds and stop. I checked the small port that provides the pulse to pump fuel and it is clean. I disassembled the carburetor and it is clean and all looks in order (based on my limited experience). I replaced the diaphram and it made no difference. The needle and seat look fine. My next thought was to bend the arm that activates the needle so that it opens sooner and further. Any other ideas short of tossing the whole blower and buying a new one. Paying to have it fixed would probably cost more than the whole thing is worth.

 

[chrisjbell]

You should be able to pick up a new carb for $40 or so. When you say you replaced the diaphragm do you mean the primer bulb or the one inside the carb? The one inside is usually a fuel pump on those little carbs and they can get a small hole (or crack) in them. The symptoms you describe are definately that the engine isn't getting fuel.

A less expensive alternative to the new carb is a rebuild kit. You'll need to track one down based on the really tiny and difficult to find numbers on the carb - you'll need a friendly and competent parts person. The rebuild on those things is tricky because the %^&! parts are so small but is pretty straightforward. Since you've already pulled it apart you probably have the idea...

Oh, I just re-read your post. If I'm interpreting correctly, the arm you are talking about bending is basically like adjusting the float in a larger carb. Give it a shot - you will (probably) be able to bend it back if you need to, and depending on the carb's rebuild kit you may be getting a new one.

 

[Dennisfly]

Thanks Chris. We are thinking alike. The diaphram that I replaced was the one inside the carburetor that, to my understanding, serves as a pump. I'll try bending the arm that activates the needle and seat valve and see what happens.

 

[oldmech]

My opinion. I think your engine is missing gas. First look if gas from tank go in carb. if yes Main jet or Float jet are blocked . The hole in main jet is VERY VERY SMALL. Often Corrosion, gum, dirt ,rust can block the jet. You can remove and with a small needle clean the small hole in the main jet. Be gentle . You can blow air in reverse side. Good luck ! Oldmech