Hello,
I recently purchased a 1968 johnson 9.5 and need to rebuild the carb. I have worked around a few outboards in the past, but am new to carbs, and am a little timid about taking on the task. I have researched what I could on the rebuilding process and consulted the sticky in the beginning of the forums and leeroys ramblings, but the information is just a little vague. I plan on taking many pictures and notes as I disassemble, but had a few questions for all you vets out there. I have printed the parts diagram, but it looks like there are a lot of little pieces/parts and I am a little put back. I am mainly concerned about cleaning the high speed jet because this was area that I diagnosed as being clogged/malfunctioning. I have been told by some to clean it out with a piece of wire, and told by others NOT to stick anything in the jet. 1) will I need a special tool to remove the high speed jet or will a small screwdriver work? 2) will soaking the parts in alcohol and blowing with air completely clean the parts? 3) does anybody have the manual for this motor that would be willing to send pics of the carb assembly instructions or willing to type some of the assembly instructions? I have been told that some screws have peened ends on them and are not meant to be removed, and removing ruins the carb. 4) any advice that you can give me to help in the assembly process? 5) any advice you can give on the adjustment process once the carb is re-assembled and re-installed? Thanks in advance!
PS, I found this, but it didn't really say how to adjust the carb once installed, any additional information would be much appreciated!
Instructions
Disassembly
1) Hold the carburetor over a shop sink and remove the drain screw from the bottom of the carburetor bowl with a screwdriver. Drain any fuel that may remain in the bowl and discard the gasket from the drain screw.
2) Unscrew the mixture screw and its spring from the top of the carburetor and unscrew the seven screws that hold the carburetor cover. Remove the cover and the gasket from the carburetor. Turn the carburetor upside down and remove the float bowl, the check ball, check valve cap and gasket
3) Push the hinge pin out with a punch. Separate the float and float valve from the carburetor as a unit and separate the float from the float valve and gasket from the float. Pull the high speed jet from the carburetor.
4) Take the the idle speed screw and its spring out of the boss on the side of the carburetor. Remove the cover on the bottom of the float bowl and remove the spring, the diaphragm, the retainer and O-ring as well as the check valve assembly from the carburetor. Take the accelerator pump cover off and remove the diaphragm and plunger.
5) Clean everything with isopropyl alcohol and blow each piece dry with compressed air, using a compressor and air hose.
The Rebuild
6) Lay out the parts of the carburetor rebuild kit and identify each. Install the check valve assembly, O-ring, retainer, diaphragm and spring, in that order into the bottom of the float bowl. Ensure the retainer's flat side is against the check valve assembly. Position the diaphragm so the outer rib fits in the cover groove.
7) Thread the high-speed jet into place in the carburetor body. Use a new gasket and install the float valve seat. Insert the float valve into the valve seat.
8) Use the hinge pin to install the float. Check float height adjustment using the cutout marked on the float gauge. Bend the float arm so that it rests between the notches on the gauge.
9) Attach the end cap. Install a new gasket on the float bowl and attach the the float bowl to the carburetor, tightening the float bowl attachment screws to 8 inch-pounds with a torque wrench, according to the sequence stamped on the top of the float bowl.
10) Thread the idle speed adjustment screw and its spring into the vertical boss on the carburetor's side until it barely touches the idle adjustment lever. Use a new gasket when you install the carburetor cover on the carburetor body. Tighten the cover screws to 8 inch-pounds using a torque wrench, in the sequence stamped on the face of the cover. Thread the idle mixture screw and its spring into the round boss on the cover until it lightly touches the seat.
I recently purchased a 1968 johnson 9.5 and need to rebuild the carb. I have worked around a few outboards in the past, but am new to carbs, and am a little timid about taking on the task. I have researched what I could on the rebuilding process and consulted the sticky in the beginning of the forums and leeroys ramblings, but the information is just a little vague. I plan on taking many pictures and notes as I disassemble, but had a few questions for all you vets out there. I have printed the parts diagram, but it looks like there are a lot of little pieces/parts and I am a little put back. I am mainly concerned about cleaning the high speed jet because this was area that I diagnosed as being clogged/malfunctioning. I have been told by some to clean it out with a piece of wire, and told by others NOT to stick anything in the jet. 1) will I need a special tool to remove the high speed jet or will a small screwdriver work? 2) will soaking the parts in alcohol and blowing with air completely clean the parts? 3) does anybody have the manual for this motor that would be willing to send pics of the carb assembly instructions or willing to type some of the assembly instructions? I have been told that some screws have peened ends on them and are not meant to be removed, and removing ruins the carb. 4) any advice that you can give me to help in the assembly process? 5) any advice you can give on the adjustment process once the carb is re-assembled and re-installed? Thanks in advance!
PS, I found this, but it didn't really say how to adjust the carb once installed, any additional information would be much appreciated!
Instructions
Disassembly
1) Hold the carburetor over a shop sink and remove the drain screw from the bottom of the carburetor bowl with a screwdriver. Drain any fuel that may remain in the bowl and discard the gasket from the drain screw.
2) Unscrew the mixture screw and its spring from the top of the carburetor and unscrew the seven screws that hold the carburetor cover. Remove the cover and the gasket from the carburetor. Turn the carburetor upside down and remove the float bowl, the check ball, check valve cap and gasket
3) Push the hinge pin out with a punch. Separate the float and float valve from the carburetor as a unit and separate the float from the float valve and gasket from the float. Pull the high speed jet from the carburetor.
4) Take the the idle speed screw and its spring out of the boss on the side of the carburetor. Remove the cover on the bottom of the float bowl and remove the spring, the diaphragm, the retainer and O-ring as well as the check valve assembly from the carburetor. Take the accelerator pump cover off and remove the diaphragm and plunger.
5) Clean everything with isopropyl alcohol and blow each piece dry with compressed air, using a compressor and air hose.
The Rebuild
6) Lay out the parts of the carburetor rebuild kit and identify each. Install the check valve assembly, O-ring, retainer, diaphragm and spring, in that order into the bottom of the float bowl. Ensure the retainer's flat side is against the check valve assembly. Position the diaphragm so the outer rib fits in the cover groove.
7) Thread the high-speed jet into place in the carburetor body. Use a new gasket and install the float valve seat. Insert the float valve into the valve seat.
8) Use the hinge pin to install the float. Check float height adjustment using the cutout marked on the float gauge. Bend the float arm so that it rests between the notches on the gauge.
9) Attach the end cap. Install a new gasket on the float bowl and attach the the float bowl to the carburetor, tightening the float bowl attachment screws to 8 inch-pounds with a torque wrench, according to the sequence stamped on the top of the float bowl.
10) Thread the idle speed adjustment screw and its spring into the vertical boss on the carburetor's side until it barely touches the idle adjustment lever. Use a new gasket when you install the carburetor cover on the carburetor body. Tighten the cover screws to 8 inch-pounds using a torque wrench, in the sequence stamped on the face of the cover. Thread the idle mixture screw and its spring into the round boss on the cover until it lightly touches the seat.