Mariner Mercury 105/140 JET, Service Manual

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5B-8 - MID-SECTION 90-824052R3 JUNE 2002
IMPORTANT: Run Trim System in short “jogs”
until pump is primed and trim system moves. If
trim motor is run without priming pump, drive-
shaft failure could result.
Cycle outboard through entire trim/tilt range 4 times.
Check fluid level after purging system.
Push down on outboard when trim rams are slightly
extended. If rams retract more than 1/8 in. (3.2 mm),
air is present in system. Cycle system again and
check fluid level.
Troubleshooting
IMPORTANT: Determine if Electrical or Hydraulic
problem exists.
IMPORTANT: Acceptable power trim leak down
should not exceed 1 in. (25.4 mm) (when mea-
sured at the tilt ram) in a 24 hour period.
HYDRAULIC SYSTEM TROUBLESHOOTING
IMPORTANT: Make one correction at a time.
Check operation of trim system before proceed-
ing to the next check.
CONDITION OF TRIM SYSTEM PROBLEM
A. Trim motor runs; trim system does not move up or down. 1, 2, 5, 10
B. Does not trim full down. Up trim OK. 2, 3, 4
C. Does not trim full up. Down trim OK. 1, 6
D. Partial or “Jerky” down/up. 1, 3
E. “Thump” noise when shifting. 2, 3, 6, 7
F. Does not trim under load. 5,8, 9,10
G. Does not hold trim position under load. 2, 5, 6
H. Trail out when backing off from high speed. 3, 4
I. Leaks down and does not hold trim. 2, 5, 7
J. Trim motor working hard and trims slow up and down. 8, 9
K. Trims up very slow. 1, 2, 8, 9
L. Starts to trim up from full down position when “IN” trim button is depressed. 3, 4
M. Trim position will not hold in reverse. 3, 4
PROBLEM
1. Low oil level.
2. Pump assembly faulty.
3. Tilt ram piston ball not seated (displaced, dirt,
nickel seat).
4. Tilt ram piston O-ring leaking or cut.
5. Manual release valve leaking (check condition of
O-rings) (Valve not fully closed).
6. Lower check valve not seating in port side trim
ram.
7. Upper check valve not seating in port side trim
ram.
8. Check condition of battery.
9. Replace motor assembly.
10. Broken motor/pump drive shaft.
External Mounted Hydraulic
System