Mercury 40 Service Manual page 146

IMPORTANT: Use of enrichener if engine is warm could result in engine flooding
No Click
Check for battery voltage to yellow/black wire at terminal block
on engine when key (or choke button) is pushed in.
Battery Voltage Indicated
Check for loose or corroded connection between yellow/black
wire and black wire (under same screw at terminal block).
Check that other black wire at terminal block is properly
grounded.
Repair connections(s) as necessary, then push key (or choke
button) in. If enrichener valve DOES NOT click, replace valve.
90-852572R1 JANUARY 1998
ENRICHENER VALVE TEST
Push Key (Or Choke Button)
In, Valve Should Click.
Check for open in circuit, yellow/black wire be-
tween key switch (or choke button) and terminal
block.
No Fuel Flow from Fitting
Remove upper hose from fitting on enrichener valve. If fuel flows
from hose, replace valve. If not, check hose and carburetor fittings
for leaks or obstructions.
Click
Squeeze primer bulb until bulb is firm. Remove lower hose from
fitting on enrichener valve. Place a container under valve, then
push key (or choke button). Check for fuel flow from fitting.
No Voltage Indicated
Fuel Flow from Fitting
Valve is O.K. Check hoses and fittings from valve to carburetors
for leaks or obstructions.
FUEL SYSTEM - 3B-19