1974 Johnson 135 HP Outboard Motors Service manual, Page 26Get this manual
CARBURETOR BODY
a Clean out aU the jets and passagesand the venturi, making sure no gum varnish deposits mainDry alter cleaning with compressed airKeep clean for final easse mbly"Figure 3- 12
b, Check all gasket su rfaces {or nicks, scratchesor distortionSlight irregula rities can be corrected with the use of surface plate nd emer cloth
cCheck throttle nd choke shafts for excessive play, Check operation of choke and throttle valves to be sur they correctly hut off air flow, yet move freel without bindingReplace carburetor body if valves or hafts are excessively worn or damaged