1988 Johnson Evinrude "CC" 9.9 thru 30 Service Manual, P/N 507660, Page 317Get this manual
Starter System Voltage Drop Test, 2030
By making systematic check from the positive battery terminal, hrough the starting circuit and back to the negative battery terminal, any component or electrical connection having excessive resi st ance can be located below
ill and remove all spark plug leads
Avoid accidental starting of engine while servicing, twist
Clean and retighten, or replace, any connection, cable, or component having greater than specified voltage drop1Connect voltmeter positive lead to battery positive postConnect voltmeter negative lead to starter solenoid positive te rminalTurn key switch to "Startto crank engine Voltage reading should not exceed 0.3 volt