1987 Johnson/Evinrude CU Outboards 35A thru 55 Service Manual, Page 92Get this manual
Primer System Servicing Functional Test Start engine and allow it to reach normal operating temperatureSet engine speed at 2000 RPM 2While engine is runningElectric start modelsPush in keyEngine should run richly and drop 1000 RPM Manual start modelsStroke primer knobEngine should run richly and drop 1000 RPM3Remove primer hose from any primer fitting that you suspect is cloggedConnect 118 inI.Dclear vinyl hose between the fitting and syringe filled with isopropyl alcohol4Press lightly on the syringe If fluid moves through the fitting, it is okay If fluid does not move through the fitting, clean with OMC Cleaning Tool PI 3266235Manual Start ModelsBe sure to check for obstructions in primer hose tee