1993 Johnson Evinrude "ET" 40 thru 55 Service Manual, P/N 508283, Page 66Get this manual
Testing
i fuel system to service which could leak liquid or vaporized
fuel, resulting in fire or explosion
'" Omitting the tank pressure test may result in returning a
Whenever fuel tank or line has been serviced or has had parts disassembled, the unit must be tested to ensure that the repaired or reassembled portion will not leak or emit fumesSimply adding fuel to the tank and checking for leakage is not an adequate test, as leakage or fumes may occur only when the tank's contents have been pressurizedAs examples, pressurization can occur when the tank is left in sunlight, or when the fuel is agitated, as might occur during transport
Tools needed are an air pressure gauge and OMC Fuel Tank Pressure Test Adapter, PIN 389945 compressed air supply is also needed