Mariner Mercury 105/140 JET, Service Manual

Page: 233 / 797

3C-26 - FUEL SYSTEMS 90-824052R3 JUNE 2002
Results: Fuel flows freely from pulse pump inlet
hose. Remove, disassemble, and inspect
pulse fuel pump (Section 3A).
IMPORTANT: All fragments of failed pump must
be located before re-assembly.
No or low fuel flow from pulse pump inlet hose. Check
for restrictions, holes, or loose connections from fuel
supply.
NOTE: Inspect anti-siphon valve on tank.
Final Filter Check and
De-pressurizing EFI System
Procedures
Purpose: Checking the final filter for obstructions,
damage etc. eliminates this component as a
possible source of restriction in the system.
Procedure: STEP 1: De-pressurize EFI fuel
system by wrapping a clean cloth around
pressure port valve and inserting tip of
screwdriver into valve, depressing valve
core. Let fuel drain from valve.
51796
a
a - Pressure Port may be located at this location on some
models.
NOTE: Pressure port valve may be located on
manifold fitting on some models.
STEP 2: Remove filter cap.
a
b
c
d
h
g
f
e
b
51796
a - Filter Housing
b - Large O-ring
c - Filter Element
d - Small O-ring
e - Filter Cap
f - Lockwasher
g - Screw
h - Cap
STEP 3: Look at filter for plugging, damage or
other signs of unusual condition.
Results: Filter is clogged with debris. Clean with
carburetor cleaner and compressed air or
replace. Recheck fuel pressure.
Filter is O.K. Pressure still below 36 psi (248 kPa).
Perform fuel pressure regulator test.