1971 Johnson 60HP outboards Service Manual, Page 25Get this manual
3-8 NEEDLE VALVES aInspect the tapered end of the needle valves for grooves, nicks, or scratches; replace if necessarySee Figure 3-14bDO NOT attempt to alter the shape of the low-speed needle valveGOOD WORN
CARBURETOR BODY
Figure 3-12Needle Valve Wear
aClean out all the jets and passages, and the venturi, making sure no gum or varnish deposits remainDry after cleaning with compressed airKeep clean for final reassemblybCheck all gasket surfaces for nicks, scratches, or distortionSlight irregularities can be corrected with the use of surface plate and emery cloth' cCheck throttle and choke shafts for excessive playCheck operation of choke and throttle valves to be sure they correctly shut off air flowyet move freely without bindingReplace carburetor body if valves or shafts are excessively worn or damaged
NOTE The threaded edges of the choke and throttle valve attaching screws are staked during carburetor assembly to prevent loss during operation, Disassembly of these valves is possible, but replacement of the carburetor body is recommendedCORE PLUGS