It is simply held in by plastic tabs on the primer bulb. All you have to do is pry behind it and easily pop it out with a flat screw driver.The tabs break easily but replacment primer bulbs are available.http://store.chainsawr.com/
A number 8 screw typically requires a size 8 screw.
the threads determine the depth the screw should move
byrumjr the line starts with the fuel filter in the tank and travels up to the carburetor out of the carburetor into the primer bulb, out of the primer bulb back in the tank raylago fuel line routing is as follows for all 2 cycle with primer ball external to the carb. remember the fuel is sucked into the carb, not puished or blown into the carb. the filtered line from the fuel tank goes to the "in" side of the carb. this is usually right next to the high speed adjustment screw on a walbro carb. the "out" line from the carb goes to the suction side of the primer ball, the output of the primer ball goes back to the return line in the fuel tank. if you have to run the choke and the carb high speed screw will not adjust properly, reverse the in and out lines to the carb.
remove the 2 bolts for the stock and then the 2 bolts that hold the trigger onto the barrel. Remove the large cap on the back of the barrel with a large screw driver. Be careful to hold it in place when removing it because it is under spring pressure. Once removed, remove the firing pin, cap, and two springs. Then cocking lever should be loose now so it will come out. You can now use the breech tool to remove the nipple and breech plug. reverse to assemble.
A 7/64 inch drill bit should be used for a 6 screw.
A 3/16 inch pilot hole should be drilled for a 10 screw.
A pilot hole of 3/32 inch should be drilled for a 6 screw.
A lock washer should be used with a screw to ensure proper fastening.
Yell
For a 1/4 screw, you should use a drill bit that is slightly smaller in diameter than the screw itself, typically a 3/16 drill bit. This will ensure a secure fit for the screw.
remove the 2 bolts for the stock and then the 2 bolts that hold the trigger onto the barrel. Remove the large cap on the back of the barrel with a large screw driver. Be careful to hold it in place when removing it because it is under spring pressure. Once removed, remove the firing pin, cap, and two springs. Then cocking lever should be loose now so it will come out. You can now use the breech tool to remove the nipple and breech plug. reverse to assemble.