1997 Johnson Evinrude "EU" 125C, 130, 200, 225, 250 90 LV Service Manual, P/N 507269, Page 111Get this manual
Recirculation System Servicing
Important disfunctional recirculation system will cause one or more of the following operational symptoms: Erratic or poor idle characteristics Fouled spark plugs in lower cylinders Excessive smoke when accelerated after extended idle Idle quality unusually sensitive to trim angle
Before proceeding with these tests, the engine's operating temperature must be above the minimum specifications listed in Section 4Function Test at Cylinder BlockAll Models
1Connect an 1s in1.0clear vinyl hose between the cylinder block hose fitting and syringe filled with isopropyl alcohol2Press lightly on the syringe plunger: Fluid should move freely through the fittingIf fluid does not move freely through the fitting, clean fitting with CWIC Nipple Cleaning Tool, PIN 326623
3Repeat Steps and for each cylinder block fittingFunction Test at Inline Check ValveV4,
1Disconnect the inline check valve from the recirculation system