Pulsa Prime Carburetor Repair

longtimealaskan

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I would greatly appreciate some thoughts on my lawn mower problem.

I was given a lawn mower with a Briggs & Stratton engine with a pulsa prime carburetor. The owner couldn稚 get it started so he gave it to me because I like to tinker. Both fuel and spark were absent. The lawn mower apparently sat outdoors for a long time since the gas tank was completely full of water.
I drained the tank and cleaned it out. I removed the carburetor, cleaned it with my air compressor, followed by carburetor cleaner, followed by another cleaning with my air compressor. I replaced the diaphragm and gasket and reassembled the carburetor/gas tank assembly.

I removed the pull start assembly and the flywheel to check the flywheel key. The key was fine, but the edge of the flywheel was covered with rust. After I cleaned the edge of the flywheel with light sandpaper followed by emery cloth, I got spark. I put some carburetor cleaner in the carburetor and started the engine. The engine ran until it used up the carburetor cleaner.
I put gas in the gas tank and found the primer wouldn稚 prime. I pulled the primer button off. It appeared to be in good condition.

I think I did everything right up to this point but now I screw things up. I thought the little ball bearing in the carburetor behind the primer might be frozen in place, although I have no idea as to its function. I started poking it gently trying to get it to move. It wouldn稚 move. I pushed a little harder and it moved all the way back to the end of the tube and it stayed there. Is there a way to reposition the ball bearing or is the carburetor shot?

But wait, there痴 more. The pulsa prime carburetor has a small tube open to the outside of the carburetor. The open tube is connected to the siphon tube. If I plug that open tube with a round dowel, the primer will prime properly and the engine will run properly.

While I apparently broke my carburetor by pushing the ball bearing too far in, I can still start and run the engine by plugging the open tube. I think I have seen pulsa prime carburetors with the 登pen tube not open. Is there anything wrong with repairing the carburetor by plugging the open tube?
 

ILENGINE

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If this is the carb i think it is. The carb is plastic, and the tube faces the fuel cap. there is suppose to be a ball bearing in that tube to seal it. I have seen more than one have the ball come out.
 

longtimealaskan

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If this is the carb i think it is. The carb is plastic, and the tube faces the fuel cap. there is suppose to be a ball bearing in that tube to seal it. I have seen more than one have the ball come out.

Thank you for your response to my question. Yes, this is a plastic carb and the open tube faces the fuel cap. Is the ball bearing a friction fit or is it secured in place with epoxy or some other type od material?
 

ILENGINE

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it is compression fit at the factory. but due to unseen forces tends to come out on occasion. I have seen various people use epoxy to seal the hole, or have seen people fit other things in there with epoxy.
 
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