TOHATSU BFT75A Service Manual page 140

dummyhead dummyhead
POWER TRIM/TILT QUICK REFERENCE CHART
Symptom
Does not Does not Does not hold
tilt up tilt down
Lowers
Pressure check
Lower chamber
hydraulic
Extends
pressure lower
than spec or
pressure drops.
Check point
Upper chamber
hydraulic
pressure lower
than spec or
pressure drops.
[1] Motor
[2] manual
valve
[3] Backup ring
O-ring
[4] Backup ring
O-ring
[5] Check valve Check the ball seat for damage or
[6] O-ring
[7] Shock relief
valve
[8] Dust seal/O-
ring
[9] Oil
[10] Pump
[11] Down relief
valve
[12] Lower
chamber check
valve
[13] Lower
chamber spool
valve
[14] Upper
chamber check
valve
[15] Upper
chamber spool
valve
TROUBLESHOOTING
Check/repair method
Check according to the motor
check procedure.
Check that the manual valve is
installed securely. Replace if it is
damaged. Check the O-ring for
damage and replace if
necessary. If there is no damage,
clean the O-ring and install it on
the manual valve properly.
Check the O-ring for damage and
replace if necessary. If there is no
damage, clean the O-ring and
reinstall it properly.
foreign material. The check valve
cannot be replaced as an
individual part. Replace the free
piston assembly if the check
valve is defective.
Check the O-ring for damage and
replace if necessary. If there is no
damage, clean the O-ring and
reinstall it properly.
Check the ball seat for damage or
foreign material. The shock valve
cannot be replaced as an
individual part. Replace the
piston rod assembly if the shock
valve is defective.
Check the dust seal and O-ring
for damage. The dust seal and O-
ring cannot be replaced as
individual parts. Replace the
piston rod assembly if the dust
seal or O-ring are defective.
Check the oil level and add the oil
if necessary.
Do not disassemble the pump
assembly. If any of the following
parts are defective, replace the
pump assembly.
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