Yamaha 55DEHD User Manual

FUEL
4-
6885J11
4-7
Fuel system
6. Apply the specified positive pressure and
check that there is no air leakage.
Disassemble the fuel pump if air leaked.
Disassembling the fuel pump
1. Remove the 3 screws securing the pump
together.
NOTE:
To disassemble the fuel pump, refer to page
4-5.
2. Check the diaphragms. Replace the
diaphragms if deteriorated or tears.
3. Check the check valves. Replace the
check valve if bend or damaged. Also,
check the fuel pump body. Replace the
fuel pump body if damaged.
Checking the fuel pump
1. Place a rag under the fuel hose connec-
tions, and then disconnect the fuel hoses
from the fuel pump.
2. Connect the special service tool 1 to the
fuel pump inlet.
3. Cover the fuel pump outlet with a finger,
and then apply the specified positive
pressure. Check that there is no air leak-
age.
4. Apply the specified negative pressure
and check that there is no air leakage.
5. Connect the special service tool 1 to the
fuel pump outlet.
Vacuum/pressure pump gauge set 1:
90890-06756
Specified positive pressure:
50 kPa (0.5 kgf/cm
2
, 7.3 psi)
69R40120
1
69R40140
1
69R40130
1
Specified negative pressure:
30 kPa (0.3 kgf/cm
2
, 4.4 psi)
Specified positive pressure:
50 kPa (0.5 kgf/cm
2
, 7.3 psi)
68840010
6885J11_04 06.10.3 11:49 Page 8

Yamaha 55DEHD Specifications

General

Brand	Yamaha
Model	55DEHD
Category	Outboard Motor
Language	English