1993 Johnson Evinrude "ET" 40 thru 55 Service Manual, P/N 508283, Page 72Get this manual
Primer System Servicing Function Test 1Start engine and allow it to reach normal operating temperatureSet engine speed at 2000 RPM2While engine is running: Electric start modelsPush key inEngine should run richly and drop 1000 RPM Manual start modelsStroke primer knobEngine should run richly and drop 1000 RPM
Remove primer hose from any primer fitting that you suspect is cloggedConnect 1S inI.Dclear vinyl hose between the fitting and syringe filled with isopropyl alcohol