Hiniker DB1474A User manual

HINIKER V-PLOW
HYDRAULIC UNIT
DB1474A
SERVICE MANUAL
DO NOT USE OR OPERATE THIS EQUIPMENT UNTIL THIS MANUAL
HAS BEEN READ AND THOROUGHLY UNDERSTOOD
PART NUMBER 25010926 Rev. A

TITLE
Introduction
POWER UNIT OPERATION
GENERAL
The hydraulic power unit consists of a 12 VDC
motor, a hydraulic pump rated at 1.9 GPM @
1600 PSI, and a valve body containing six nor-
mally closed electric solenoid valves and three
adjustable pressure relief valves. The uid sup-
ply line for the pump is submerged in a 2.5 quart
capacity reservoir and is ltered by a 149 micron
screen.
The valve body directs hydraulic uid to oper-
ate six hydraulic circuits, raise, lower, angle left,
angle right, vee and scoop. The raise, angle and
scoop circuits receive uid under pressure, and
the lower and vee circuits do not, however, pres-
sure is generated as uid returns to the reser-
voir.
RAISE MODE OF OPERATION
Operating the Raise switch energizes the 12
VDC motor, the S3 solenoid valve and de-en-
ergizes the S4 solenoid valve. Hydraulic uid
under pressure is then directed through the S3
solenoid valve and a one way check valve (CV2)
to the lift cylinder.
Releasing the Raise switch de-energizes the
12 VDC motor and the S3 solenoid valve. The
one way check valve (CV2) maintains hydraulic
pressure in the lift cylinder.
The raise circuit is protected by a pressure relief
valve (SYSRV) set to relieve system pressure at
2250 PSI. Typically, pressure is relieved when
the lift cylinder reaches the full up position.
LOWER MODE OF OPERATION
Operating the Lower switch energizes the S4 so-
lenoid valve, lowers the blade and establishes a
oat circuit. The oat circuit allows uid to enter
or exit the lift cylinder allowing the blade to fol-
low the contour of the ground.
ANGLE LEFT MODE OF OPERATION
Operating theAngle Left switch energizes the 12
VDC motor, the S5 solenoid valve and the S2
solenoid valve. Hydraulic uid under pressure is
then directed through the S5 solenoid valve and
a one way check valve (CV3) to the right wing
cylinder. Hydraulic uid, not under pressure, is
directed from the left wing cylinder through the
S2 solenoid valve back to the reservoir as the
cylinder retracts.
Releasing the Angle Left switch de-energizes
the 12 VDC motor, the S5 solenoid valve and
the S2 solenoid valve. The one way check valve
(CV3) maintains hydraulic pressure in the right
wing cylinder.
The right wing circuit is protected by a pressure
relief valve (RV2) set to relieve system pressure
at 2700 PSI. Typically, pressure is relieved when
the right wing cylinder reaches its fully extended
position.
ANGLE RIGHT MODE OF OPERATION
Operating the Angle Right switch energizes the
12 VDC motor, the S1 solenoid valve and the S6
solenoid valve. Hydraulic uid under pressure is
then directed through the S1 solenoid valve and
a one way check valve (CV1) to the left wing
cylinder. Hydraulic uid, not under pressure, is
directed from the right wing cylinder through the
S6 solenoid valve back to the reservoir as the
cylinder retracts.
Releasing the Angle Right switch de-energizes
the 12 VDC motor, the S1 solenoid valve and
the S6 solenoid valve. The one way check valve
(CV1) maintains hydraulic pressure in the left
wing cylinder.
The left wing circuit is protected by a pressure
relief valve (RV1) set to relieve system pressure
at 2700 PSI. Typically, pressure is relieved when
the left wing cylinder reaches its fully extended
position.

Introduction
VEE MODE OF OPERATION
Operating the Vee switch energizes the S2 sole-
noid valve and the S6 solenoid valve. An exten-
sion spring on the moldboard forces hydraulic
uid, not under pressure, from the left wing cyl-
inder through the S2 solenoid valve back to the
reservoir as the cylinder retracts. Likewise, hy-
draulic uid, not under pressure, is forced from
the right wing cylinder through the S6 solenoid
valve to the reservoir as the cylinder retracts.
Releasing the Vee switch de-energizes the S2
and S6 solenoid valves.
SCOOP MODE OF OPERATION
Operating the Scoop switch energizes the 12
VDC motor, the S1 solenoid valve and the S5
solenoid valve. Hydraulic uid under pressure is
then directed through the S1 solenoid valve and
a one way check valve (CV1) to the left wing
cylinder. Hydraulic uid under pressure is also
directed through the S5 solenoid valve and a
one way check valve (CV3) to the right wing cyl-
inder.
Releasing the Scoop switch de-energizes the 12
VDC motor, the S1 solenoid valve and the S5
solenoid valve. The one way check valves, CV1
and CV3, maintain hydraulic pressure in their re-
spective wing cylinders.
The left wing circuit is protected by a pressure
relief valve (RV1) and the right wing circuit is
protected by another pressure relief valve (RV2).
Both are set to relieve system pressure at 2700
PSI.Typically,pressureisrelievedwhenthewing
cylinders reach their fully extended position.

TITLE
POWER UNIT - V PLOW
Power Unit - Hydraulic
DWG NO. 5457

TITLE
POWER UNIT - COMPONENT LOCATION
REF.
NO. PART NUMBER DESCRIPTION QTY. REF. NO. PART NUMBER DESCRIPTION QTY.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
25010230
25010214
25010235
25010734
25010334
950-011-049
25010332
25010221
25010236
25010738
950-004-071
25010217
25010436
25010992
25010762
950-004-095
25010744
DC Motor 12 V
Coupling
Pin 1/8 x 1/4
PumpAssembly
Pump O-Ring Kit
Torx Hd Bolt 5/16-24 x 3 GR 8
Inlet Plumbing Kit
Filter
O-Ring
Reservoir
Machine Screw # 12-24 x 1/2 Hex Washer Head
Breather
Decal Tank Fill Line
O-Ring Kit (Release & Check)
Manifold O-Ring Kit
Socket Head Cap Screw 1/4-20 x 2 1/2
Return Tube
1
1
3
1
1
2
1
1
1
1
4
1
1
12
1
3
1
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
25010745
25010746
25011065
25010542
25010243
25010761
950-004-072
25010220
25010733
25010985
25010763
25011064
25010930
25010929
25011066
25010748
Return Tube Filter
Check Valve
Release Valve Kit, Single Spade Coil
Flow Control Valve
Plumbing Plug
Plug 1/8 NPT
Machine Screw 1/4-20 x 1/4 Hex Washer Head
Plumbing Magnet
Finished End Head
Relief Valve
Spring & BallAssembly
Valve Block
Compression Tube Sleeve
Compression Tube Nut
Cartridge Release Valve
Solenoid Coil
1
3
6
1
10
6
1
1
1
3
1
1
1
1
6
6
DWG NO. 4213
25011062 Power Unit
Power Unit - Component Location

TITLE
Power Unit - Hydraulic
POWER UNIT - V PLOW
SYSRV
RV1
S2 W1 S6
S5
CV3
RV1
S6
S6
RV2
L
S2
S4 S5 S1
S4
S6
CV2
RV2
W2 S2
S3
CV3
S6
CV1
S2
S4 S2
VIEW A-A
A
A
B
BVIEW B-B
DWG NO. 3711

TITLE
Power Unit - Component Location
POWER UNIT - COMPONENT LOCATION
31
20
32
19
12
33
14
22
9
26
17
25
5
20 (14,32,33)
18
27
4
8
7
6
20
24
15
23
16
19
3
20
28
13 21
19 11
12
10
14
29
30
14
14
29
30
34
(14,32,33)
20 (14,32,33)
20 (14,32,33)
(14,32,33)
REF.
NO. PART NUMBER DESCRIPTION QTY. REF. NO. PART NUMBER DESCRIPTION QTY.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
25010230
25010214
25010235
25010734
25010334
950-011-049
25010332
25010221
25010236
25010738
950-004-071
25010217
25010740
25010784
25010762
950-008-025
25010744
DC Motor 12V
Coupling
Pin 1/8x1/4
PumpAssembly
Pump O-Ring Kit
Torx Head Bolt 5/1 6-24 x 3 Gr. 8
Inlet Plumbing Kit
Filter
O-Ring
Reservoir
Machine Screw #12-24 x 1/2 Hex Washer Head
Breather
Valve Block
Cartridge & Relief Valve 0-Ring Kit
Manifold 0-Ring Kit
1/4-20 x 2 1/2 Socket Head Set Screw
Return Tube
1
1
3
1
1
2
1
1
1
1
4
1
1
1
1
3
1
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
25010745
25010746
25010766
25010542
25010243
25010761
950-004-072
25010220
25010733
25010436
25010763
25010774
25010518
25010337
25010748
25010544
25010791
Return Tube Filter
Check Valve
Release Valve Kit
Flow Control Valve
Plumbing Plug
Plug 1/8 NPT
Machine Screw 1/4-20 x 1/4 Hex Washer Head
Plumbing Magnet
Finished End Head
Decal Tank Fill Line
Spring & BallAssembly
Relief Valve Kit
Relief Valve O-Ring
Motor Brush Kit
Solenoid Coil
Cartridge Release Valve
Relief Valve Kit
1
3
6
1
6
5
1
1
1
1
1
2
3
1
1
1
1
DWG NO. 3708
25010732 Power Unit

TITLE
POWER UNIT - HYDRAULIC CIRCUIT DIAGRAM
Power Unit - Hydraulic Circuit Diagram
DWG NO. 4182A

TITLE
TABLE OF CONTENTS
25010926 Rev. A 3/05 Manual/25010926RevA
Troubleshooting Procedures....................................................................................................... 2
V-Plow Will Not Raise.................................................................................................................. 3
V-Plow Lifts Slowly ...................................................................................................................... 4
V-Plow Will Not Stay Up.............................................................................................................. 5
V-Plow Will Not Lower................................................................................................................. 6
Left Wing Will Not Extend ........................................................................................................... 7
Right Wing Will Not Extend......................................................................................................... 8
Left Wing Will Not Stay Extended............................................................................................... 9
Right Wing Will Not Stay Extended.......................................................................................... 10
Left Wing Will Not Retract..........................................................................................................11
Right Wing Will Not Retract ...................................................................................................... 12
DC Motor Removal and Replacement...................................................................................... 13
DC Motor Brush Removal and Replacement........................................................................... 14
Check Valve Removal, Cleaning & Replacement (CV1, CV2, CV3)...................................... 15
Relief Valve Removal, Cleaning & Replacement .................................................................... 16
System Relief Valve Removal, Cleaning & Replacement....................................................... 17
Relief Valve 1 (RV1) Removal, Cleaning & Replacement...................................................... 18
Relief Valve 2 (RV2) Removal, Cleaning & Replacement...................................................... 19
Solenoid Valve Removal, Cleaning and Replacement.......................................................20-21
Valve Block Removal, Cleaning and Replacement................................................................. 22
Hydraulic Pump Removal, Cleaning and Replacement.....................................................23-25
Flow Control Valve Removal, Cleaning and Replacement................................................26-27
Hydraulic Pump Test ................................................................................................................. 28
System Relief Valve Testing and Adjustment.....................................................................29-30
Relief Valve Testing and Adjustment ..................................................................................31-32
DC Motor Current Draw (Full Load).......................................................................................... 33
DC Motor Current Draw (No Load)........................................................................................... 34
Solenoid Valve Test................................................................................................................... 35
Relief Valve Testing and Adjustment ..................................................................................36-37
Table of Contents 1

TITLE
TROUBLESHOOTING PROCEDURES
INTRODUCTION
This section is designed to help you troubleshoot
the hydraulic system on the Hiniker V-Plow.
Each procedure consists of a detailed problem
description followed by a step-by-step ow chart
that will direct you to do certain service or test
procedures. If each service or test procedure is
done step-by-step in the order given, the prob-
lem can usually be corrected.
INITIAL INSPECTION
1. Make sure vehicle is in park and parking
brake is set.
2. Retract wings fully and lower plow to the
ground before servicing any part of the hy-
draulic or electrical systems.
3. Inspect all wiring harness connectors for:
A. Corrosion or dirt in and/or on Pins and
Sockets.
B.Damagedormissing Pinsand/orSockets.
C. Full engagement of Pins into respective
Sockets.
4. Check Ground.
A.Makesurebatterygroundtovehicleframe
is clean, corrosion free and tight.
B. Make sure that ground connections from
the Snow Plow harness to vehicle frame
or battery are clean, corrosion free and
tight.
5. Verify the correct hydraulic uid is being
used in unit and make sure oil level is to “Fill
Line” when the plow is on the ground and
the wings retracted.
6. Check all hoses and cylinders for proper
condition and leaks.
7. Make sure battery is charged and charging
system is in good condition.
8. Check 10 AMP fuse located on the Under-
hood Wiring Harness. Replace if bad.
9. Make sure joystick controller is connected in
the cab and turned on.
2 Troubleshooting

TITLE
V-Plow Will Not Raise 3
V-PLOW WILL NOT RAISE
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
V-PLOW WILL NOT RAISE
ALL OTHER FUNCTIONS ARE NORMAL.
DOES PUMP MOTOR RUN?
Perform Solenoid Valve Test to S3 Solenoid
Valve. Repair or replace as necessary.
See page 35.
Does V-Plow raise?
Refer to electrical troubleshooting.
Does pump motor run?
Turn ignition switch on and momentarily ac-
tivate the RAISE switch on the joystick con-
trol box to ensure that the FLOAT mode is
OFF. Check S4 Solenoid Valve for magne-
tism by loosely holding metal end of screw-
driver within 1/8” of the nut end of the S4
Solenoid Valve Coil.
Is screwdriver attracted to nut end of coil?
Remove, inspect and clean System Relief
Valve. Repair or replace as necessary. See
page 16 or 17. Reinstall and adjust.
See page 29 or 36. Does V-Plow raise?
Remove, inspect and clean S4 Solenoid
Valve. See page 20. Repair or replace as
necessary. Does V-Plow raise?
Check ttings and lift cylinder hose for ob-
structions. Remove lift cylinder and drain
oil. Check for a frozen/binding cylinder by
manually compressing and extending the
cylinder. Repair or replace as necessary.
Does V-Plow raise?
Call Hiniker Service Does V-Plow Raise?
Call Hiniker Service
Yes No
No Yes End
No Yes
No Yes End
No Yes End
YesNo End
YesNo
End
YesNo

TITLE
V-PLOW LIFTS SLOWLY
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
V-PLOW LIFTS SLOWLY
ALL OTHER FUNCTIONS ARE NORMAL.
Remove, inspect and clean System Relief Valve.
See page 16 or 17.
Adjust pressure. See page 31 or 36.
DOES V-PLOW LIFT FULLY UP IN APPROXIMATELY 2 SECONDS?
Remove, inspect and clean S3 Solenoid
Valve See page 20.
Repair or replace as necessary. Does V-
Plow lift fully up in approximately 2 sec-
onds?
Check ttings and lift cylinder hose for ob-
structions. Remove, lift cylinder and drain
oil. Check for a binding cylinder by manu-
ally compressing and extending the cylin-
der. Repair or replace as necessary. Does
V-Plow lift fully up in approximately 2 sec-
onds?
YesNo
YesNo End
Yes
No
Note: Until pump system warms, slow functioning of the V-Plow will occur in extremely cold tempera-
tures unless a high quality oil that is appropriate for the temperatures in which you will be plow-
ing snow is used. See chart below.
Note: Ensure vehicle battery is fully charged and alternator output is 13.6 Volts minimum with engine
running and no accessories on.
End
Call Hiniker Service DWG NO. 3066
4 V-Plow Lifts Slowly

TITLE
V-PLOW WILL NOT STAY UP
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
V-PLOW WILL NOT STAY UP.
ALL OTHER FUNCTIONS ARE NORMAL.
Remove, inspect and clean Check Valve 2 (CV2)
See page 15.
Repair or replace as necessary.
DOES V-PLOW STAY UP?
Momentarily activate the RAISE switch on
the joystick control box to ensure that the
oat mode is OFF. Verify that there is no
voltage at the S4 Solenoid Valve, using a
voltmeter or test light. Is voltage present?
Remove, inspect and clean S4 Solenoid
Valve.
See page 20.
Repair or replace as necessary.
Does V-Plow stay up?
YesNo
YesNo
End
Call Hiniker Service
Refer to electrical troubleshooting.
Does V-Plow say up?
V-Plow Will Not Stay Up 5
YesNo End
YesNo End

TITLE
V-PLOW WILL NOT LOWER
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
V-PLOW WILL NOT LOWER
ALL OTHER FUNCTIONS ARE NORMAL.
Perform Steps 1 thru 5 of the
Solenoid Valve Test to Solenoid Valve S4.
See Page 35.
DO NOT REPLACE CARTRIDGE VALVE
AT THIS TIME.
DOES V-PLOW LOWER?
Support plow blade (same as the left paragraph).
Check for plugged ttings and hydraulic hose.
Remove and drain oil from lift cylinder. Check for
frozen/binding cylinder by manually compressing
and extending the cylinder.
Repair or replace as necessary.
Does V-Plow lower?
Support plow blade with a oor Jack or
other suitable means. Relieve hydrau-
lic pressure by loosening hose tting on
lift cylinder. Remove, inspect and clean
S4 Solenoid Valve. See page 20. En-
sure plunger pushes in approx. 1/16”
and springs back. If it does not, replace
cartridge valve. Remove, inspect and
clean Flow Control Valve. See page 26.
Does V-Plow lower?
YesNo
YesNo
End
Call Hiniker Service
YesNo End
6 V-Plow Will Not Lower
End

TITLE
Left Wing Will Not Extend 7
LEFT WING WILL NOT EXTEND
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
LEFT WING WILL NOT EXTEND
ALL OTHER FUNCTIONS ARE NORMAL.
Move joystick on controller to
“Right” position.
DOES PUMP MOTOR RUN?
Remove, inspect and clean S2 Solenoid Valve.
Repair or replace as necessary. See page 20.
Does Left Wing Extend?
Perform Solenoid Valve Test to S1 So-
lenoid Valve. Repair or replace as nec-
essary. See page 35.
Does Left Wing Extend?
Yes No
YesNo
Call Hiniker Service
YesNo
End
End
Refer to electrical troubleshooting.
Does pump motor run?
Remove, inspect and clean Relief Valve
1 (RV1). Repair or replace as necessary.
See page 16 or 18. Reinstall and adjust.
See page 31 or 36.
Does Left Wing Extend?
YesNo
NoYes
Does Left Wing Extend?
YesNo End

TITLE
RIGHT WING WILL NOT EXTEND
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
RIGHT WING WILL NOT EXTEND
ALL OTHER FUNCTIONS ARE NORMAL.
Move joystick on controller to
“Left” position.
DOES PUMP MOTOR RUN?
Remove, inspect and clean S6 Solenoid Valve.
Repair or replace as necessary. See page 20.
Does Right Wing Extend?
Perform Solenoid Valve Test to S5 So-
lenoid Valve. Repair or replace as nec-
essary. See page 35.
Does Right Wing Extend?
Yes No
YesNo
Call Hiniker Service
YesNo
End
End
Refer to electrical troubleshooting.
Does pump motor run?
Remove, inspect and clean Relief Valve
2 (RV2). Repair or replace as necessary.
See page 16 or 19. Reinstall and adjust.
See page 31 or 36.
Does Right Wing Extend?
YesNo
NoYes
Does Right Wing Extend?
YesNo End
8 Right Wing Will Not Extend

TITLE
LEFT WING WILL NOT STAY EXTENDED
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
LEFT WING WILL NOT STAY EXTENDED
ALL OTHER FUNCTIONS ARE NORMAL.
Remove, inspect and clean Check Valve 1 (CV1).
See page 15.
Repair or replace as necessary.
DOES LEFT WING STAY EXTENDED?
Remove, inspect and clean
S2 Solenoid Valve. See page 20.
Repair or replace as necessary.
Does Left Wing Stay Extended?
YesNo
Call Hiniker Service
YesNo End
Remove, inspect and clean Relief Valve
1 (RV1). See page 18. Repair or replace
as necessary. Reinstall and adjust.
See page 31.
Does Left Wing Stay Extended?
YesNo
End
Left Wing Will Not Stay Extended 9

TITLE
RIGHT WING WILL NOT STAY EXTENDED
Perform all initial inspections and checks listed on page 1 before beginning test procedure.
WARNING: Always retract wings fully, lower the plow to the ground and relieve pressure
before removing any ttings, hoses or caps. Allow the system to cool down before drain-
ing oil or handling system components. Serious burns can result from contact with hot
oil. FAILURE TO HEED CAN RESULT IN SERIOUS INJURY OR DEATH.
RIGHT WING WILL NOT STAY EXTENDED
ALL OTHER FUNCTIONS ARE NORMAL.
Remove, inspect and clean Check Valve 3 (CV3).
See page 15.
Repair or replace as necessary.
DOES RIGHT WING STAY EXTENDED?
Remove, inspect and clean
S6 Solenoid Valve. See page 20.
Repair or replace as necessary.
Does Right Wing Stay Extended?
YesNo
Call Hiniker Service
YesNo End
Remove, inspect and clean Relief Valve
2 (RV2). See page 19. Repair or replace
as necessary. Reinstall and adjust.
See page 31.
Does Right Wing Stay Extended?
YesNo
End
10 Right Wing Will Not Extend