2004 SR Johnson 2-stroke 40, 50HP Service Manual, Page 147Get this manual
FUEL SYSTEM FUEL SYSTEM TESTS
Fuel Pump Test
40R, 40RL MODELS
Before testing, loosen fuel tank gas cap momentarily to release any pressureFuel tank must not be more than 30 in(76 cm) below fuel pumpRemove carburetor to fuel pump hoseConnect fuel pressure gauge between carburetor and second fuel pumpInstall test prop
Primer Pump Test
40R, 40RL MODELS
STEP Start engine and allow it to reach normal operating temperature Set engine speed at 2000 RPM While engine is running, operate the primer knob and observe engine speedTurn engine OFF
Results: If outboard slows approximately 1000 RPMprimer circuit is functional If primer does not affect speed, proceed to STEP 2STEP Remove primer hoses from fittings at top of carburetorsConnect 18 inI.Dclear vinyl hose between each fitting and Syringe, PIN 346936, filled with isopropyl alcoholPress lightly on the syringe
Run outboard and check gaugeRefer to chart below
600 2500 to 3000 4500 psi 1.5 psi 2.5 psi