e-72 power unit service manual - meyer products
TRANSCRIPT
FORM NO. 1-1047January 2012
E-72power unit
service manual
© 2012 Printed in the U.S.A.
Meyer Products LLC18513 Euclid Ave. • Cleveland, Ohio 44112-1084
Phone 486-1313 (Area Code 216)www.meyerproducts.com• email [email protected]
FOREWARD
This Service Manual includes complete information for servicing the following Electro Lift® Units:
E-72
IMPORTANT: Maintenance and repairs must be performed with the moldboard on the
ground.
The information is grouped according to the type of work being performed, such as diagnosis andtesting, disassembly and reassembly. Special tools and specifications are also included in this manual.
All information, illustrations and product descriptions contained in this manual are correct at publicationtime. We do, however, reserve the right to make changes at any time without prior notice.
MEYER PRODUCTS INC.
SECTION INDEX
Section Number Section Title ..................................................... Page
0 GENERAL INFORMATION ANDMAINTENANCE ........................................................ 1
1 GENERAL DESCRIPTION ANDTHEORY OF OPERATION ........................................ 4
2 DIAGNOSIS ............................................................. 143 REPAIR PROCEDURE .............................................. 204 CONTROLLER TROUBLESHOOTING .................... 435 SPECIFICATIONS ..................................................... 44
Meyer Products Inc. reserves the right, under its continuing product improvement program, to change construction ordesign details, specifications and prices without notice or without incurring any obligation.
SECTION 0 - GENERAL INFORMATION AND MAINTENANCE
CONTENTS
GENERAL INFORMATION .................................................. 2
• MODEL IDENTIFICATION .................................................... 2
• MODEL IDENTIFICATION AND
SERIAL NUMBER LOCATION .............................................. 2
• MOTOR IDENTIFICATION ................................................... 2
MAINTENANCE ................................................................... 2
• GENERAL MAINTENANCE ................................................... 2
• CLEANLINESS ................................................................. 2
• VEHICLE ELECTRICAL SYSTEM........................................... 2
• CHECK REGULARLY ........................................................ 2
POST-SEASON MAINTENANCE ........................................... 2
• MEYER HYDRAULIC FLUID M-1 ......................................... 2
• REPLACEMENT OF HYDRAULIC FLUID ................................... 3
• FILTERS ........................................................................ 3
• PROTECTION AGAINST RUST
AND CORROSION ............................................................ 3
-1-
Vehicle Electrical System
Maximum performance and efficiency of the ElectroLift® unit requires that the vehicle’s electrical systembe properly maintained and consist of:
Battery ----------- 70 Amp. Hr. Minimum or550 Cold Cranking Amps.
Alternator ------ 60 Amp. Minimum
Check Regularly
1. Battery Terminals - Must be clean and free ofcorrosion.
2. Electrical Connections - Must be free of corrosionand tight.
3. Battery - Must be in first-class condition.4. Alternator (or Generator) and Regulator - Must be
functioning to specifications.5. Hydraulic Fluid Reservoir Level - A significant drop
in hydraulic fluid level indicates a leak which mustbe located and corrected. Insufficient hydraulic fluidmay result in severe damage.
POST-SEASON MAINTENANCE
Meyer Hydraulic Fluid M-1.
Meyer Hydraulic Fluid M-1 is a specially formulatedmineral oil which maintains an almost constantviscosity from normal to sub-zero temperatures.Because it remains free flowing at extremely lowtemperatures, the performance and efficiency are notaffected.
Meyer Hydraulic Fluid M-1 also contains an additivewhich neutralizes moisture accumulating in the fluiddue to condensation. It is effective for a maximum ofone year’s use.
Meyer Products Inc. will not be liable for damagesresulting from the use of inferior or other fluids oroils.
GENERAL INFORMATION
Model IdentificationThe E-72 unit is an electrically powered hydraulicmechanism specifically designed for use with the MeyerE-Z Mount Plus and Drive Pro Snow Plow systems.
Model Identification and Serial Number LocationInclusion of the model number and serial number isextremely important when writing up warranty claimforms and product report forms for proper evaluationand follow up.
The basic model number is located on the nameplate (plastic cover). The serial number is locatedon the name plate decal underneath the plastic cover.
MAINTENANCEThe following maintenance information is intended asa basic guide for providing the E-72 unit with the properservice and care. Sustained heavy duty operation oroperating under adverse conditions may necessitatemore frequent servicing.
General Maintenance
CleanlinessThe greatest enemy to any hydraulic system is dirt orcontamination. Therefore, cleanliness must be stressedat the time of installation, servicing and repairing.
-2-
Replacement of Hydraulic Fluid
After a season’s use, completely drain the hydraulicfluid (including hydraulic fluid in hoses andcylinders). Drain fluid through drain plug shown inFigure 0-1. Disconnect the fittings at the Angling andLift cylinders and completely retract the cylinder rodsand purge cylinders and hoses of all hydraulic fluid.Flush the complete system including unit, hoses andangling rams with the M-2 Flushing Fluid, or a nonwax (Napthenic) cleaner. If kerosene (Parrafinic) is usedto flush the system, the system must be flushed againto remove any kerosene with M-2 Flushing Fluid, or a(Napthenic) based cleaner that is wax free.
Refill E-72 unit with M-1 Fluid by fully retracting lift rod(Ram) and filling reservoir to the fill mark on the sideof the reservoir. Fill and bleed hoses and Power Anglingcylinders by loosening hydraulic fittings at cylindersuntil they leak. Power angle plow repeatedly from oneside to the other until fluid flows steadily from theleaking fittings while maintaining a constant check onthe reservoir fluid level.
Raise and lower the plow several times and with liftrod fully retracted, give a final check to the fluidlevel and replace filler plug.
Protection Against Rust and Corrosion
When the E-72 unit is not used for extended periods,protect the chromed lift rod (Ram) by fully extendingit and coating it with chassis lubricant. Full extensionof the lift rod (Ram) fills the cylinder with hydraulicfluid. Coat the exposed portions of the Power Anglingcylinder rods (Rams) with chassis lubricant to protectthem against rust and corrosion.
FIGURE 0-1
-3-
Filler Plug
Drain Plug
SECTION 1 - GENERAL DESCRIPTION AND THEORY OF OPERATION
CONTENTS
GENERAL DESCRIPTION ................................................................................................. 5
THEORY OF OPERATION................................................................................................. 5
• FUNCTIONS .................................................................................................................. 5
• ELECTRICAL AND FLOW CHARTS ...................................................................................... 6-9
ELECTRO LIFT® UNIT COMPONENTS ......................................................................... 9
• MOTORS ...................................................................................................................... 9
•• Iskra .................................................................................................................... 9
• HYDRAULIC PUMP .......................................................................................................... 9
• PRESSURE RELIEF VALVE ................................................................................................ 9
• SOLENOID VALVES ......................................................................................................... 9-10
•• Cartridge ............................................................................................................ 9-10
•• Coil ...................................................................................................................... 9-10
“A” Solenoid Valve ............................................................................................. 11
“B” Solenoid Valve ............................................................................................ 11
“C” Solenoid Valve ........................................................................................... 11
• CHECK VALVES .............................................................................................................. 11
• PILOT CHECK VALVE ...................................................................................................... 11
• CROSSOVER RELIEF VALVES ............................................................................................ 12
• SOLENOID SWITCH ........................................................................................................ 12
• FILTERS ....................................................................................................................... 12
-4-
GENERAL DESCRIPTION
E-72 unit is an electrically powered and electricallycontrolled hydraulic mechanism specifically designedfor use with Meyer Snow Plows. The E-72 raises andlowers the plow with a remote 8" stroke hydraulic liftcylinder.
In addition to raising and lowering the plowhydraulically, the E-72 angles the plow hydraulically,left and right, via remote hydraulic cylinders.
The Electro Lift® unit consists of a specially designedhigh torque 12-volt DC motor which is directly coupledto a gear-type hydraulic pump. The pump obtains itssupply of hydraulic fluid from an integral reservoir whichtotally surrounds the integral hydraulic cylinder whichraises and lowers the plow.
The E-72 includes an integral valve body which containsthree electrically controlled solenoid valve cartridges.Solenoid valve cartridge “A” which is energized to allowthe plow to lower by gravity. Solenoid valve cartridge“B” is energized to route the pressurized hydraulic fluidto the remote hydraulic lift cylinder to raise the plow.Solenoid valve cartridge “C” is energized to route thepressurized hydraulic fluid to the left remote hydrauliccylinder to angle the plow to the right. When allcartridge are not energized and the motor is runningthe pressurized hydraulic fluid will flow to the rightremote hydraulic cylinder to angle the plow to the left.
Additional components which control and supplyelectrical current to the E-72 units are an operatorcontrolled Pistol Grip controller; a solenoid switch tosupply high amperage current to the unit’s motor(motor solenoid); valve cartridge(s); and short heavygauge cables to distribute high amperage currentdirectly from the positive terminal of the vehicle’sbattery and ground the unit directly to the negativeterminal of the vehicle’s battery.
THEORY OF OPERATION
FUNCTIONS
Refer to Figures 1-1 through 1-4 (pages 6 thru 9) forelectrical and hydraulic flow chart for each function.Each figure explains which component is actuated andrelated in each function.
The E-72 four basic functions performed are:
• Raise snow plow• Lower snow plow• Angle snow plow to right• Angle snow plow to left
-5-
E-7
2 R
aise
, Mo
tor
and
“B
” S
ole
noid
-6-
FIGURE 1-1
ST
RA
INE
R
LIF
TC
YLI
ND
ER
RE
TUR
N T
O
RE
SE
RV
OIR
A
B
LOW
ER
A
DJU
ST
ME
NT
DU
AL
PIL
OT
CH
EC
K
RA
ISE
CR
OS
S-O
VE
R
RE
LIE
F V
ALV
E38
00 +
400
P.S
.I. PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PU
MP
CH
EC
K V
ALV
E
PU
MP
PR
ES
SU
RE
RE
LIE
F VA
LVE
AD
JUS
TAB
LEO
PE
NS
at 2
000
+ 50
P.S
.I.
EN
ER
GIZ
ED
NO
TE
NE
RG
IZE
D
NO
T E
NE
RG
IZE
D
C
Res
ervo
ir
E-7
2 Lo
wer
, “A
” S
ole
noid
-7-
FIGURE 1-2
ST
RA
INE
R
LIF
TC
YLI
ND
ER
RE
TUR
N T
O
RE
SE
RV
OIR
A
B
LOW
ER
A
DJU
ST
ME
NT
DU
AL
PIL
OT
CH
EC
K
LOW
ER
CR
OS
S-O
VE
R
RE
LIE
F V
ALV
E38
00 +
400
P.S
.I. PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PU
MP
CH
EC
K V
ALV
E
PU
MP
PR
ESS
UR
E R
ELI
EF
VALV
E
A
DJU
STA
BLE
OP
EN
S at
200
0 +
50 P
.S.I.
NO
T E
NE
RG
IZE
D
NO
TE
NE
RG
IZE
D
EN
ER
GIZ
ED
C
Res
ervo
ir
E-7
2 A
ngle
Lef
t, M
oto
r o
nly
-8-
FIGURE 1-3
ST
RA
INE
R
LIF
TC
YLI
ND
ER
RE
TUR
N T
O
RE
SE
RV
OIR
A
B
LOW
ER
A
DJU
ST
ME
NT
DU
AL
PIL
OT
CH
EC
K
AN
GLE
LE
FT
CR
OS
S-O
VE
R
RE
LIE
F V
ALV
E38
00 +
400
P.S
.I. PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PU
MP
CH
EC
K V
ALV
E
PU
MP
PR
ES
SU
RE
RE
LIE
F VA
LVE
AD
JUS
TAB
LE O
PE
NS
at 2
000
+ 50
P.S
.I.
NO
T E
NE
RG
IZE
D
NO
T E
NE
RG
IZE
D
NO
T E
NE
RG
IZE
D
C
Res
ervo
ir
E-7
2 A
ngle
Rig
ht,
Mo
tor
and
“C
” S
ole
noid
-9-
FIGURE 1-4
ST
RA
INE
R
LIF
TC
YLI
ND
ER
RE
TUR
N T
O
RE
SE
RV
OIR
A
B
LOW
ER
A
DJU
ST
ME
NT
DU
AL
PIL
OT
CH
EC
K
AN
GLE
RIG
HT
CR
OS
S-O
VE
R
RE
LIE
F V
ALV
E38
00 +
400
P.S
.I. PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PO
WE
R A
NG
LIN
G
CY
LIN
DE
RS
PU
MP
CH
EC
K V
ALV
E
PU
MP
PRE
SSU
RE
RE
LIE
F VA
LVE
NO
N A
DJU
STA
BLE
OP
EN
S a
t 200
0 +
50 P
.S.I.
NO
T E
NE
RG
IZE
D
EN
ER
GIZ
ED
NO
T E
NE
RG
IZE
D
C
Res
ervo
ir
Under a condition, such as when a hydrauliccylinder is extended to the end of its stroke,eliminating additional space for the pressurizedhydraulic oil to be pumped into, the alternateopening and closing of the poppet valve controlsthe pump’s pressure output and provides an escapefor the pressurized hydraulic fluid.
The pressure relief valve used in the E-72 hydraulicunit, while more sophisticated than the one described,functions in the same manner. The pump pressure reliefvalve may be adjusted to the specified pressure of2000 P.S.I. by adjusting the set screw after installing asuitable pressure gauge of 2500 P.S.I. in the circuit.
SOLENOID VALVES
Hydraulic valves are simple in concept and all havethe same basic function: Control the direction of oilflow.
Each Solenoid Valve consists of two components:the Cartridge and the Coil.
Cartridge
The Cartridge consists of the hydraulic valvemechanism and an armature which enables thevalve mechanism to be operated and controlledelectrically. The Cartridge is designed to screw inand out of the E-72 units much like the typical“spark plug”.
Coil
FIGURE 1-7
COIL
VALVE SPOOL
WINDING
ARMATURE
FIGURE 1-5
ELECTRO LIFT® UNIT COMPONENTS
RESERVOIR
ELECTRICMOTOR
FLOW
OUTLET LINE
INTAKE LINE
PUMP CHAMBER
PUMP HOUSING
DRIVE GEARDRIVEN GEAR
FLOW
OUTLET PORT
POPPET VALVE
VALVE SPRING
PUMP HOUSING
INLET PORT
FIGURE 1-6
-10-
PRESSURE RELIEF VALVE
A basic pressure relief valve is shown inFigure 1-6. It consists of a poppet valve and a valvespring. Both are located in a passage which connectsthe inlet passage to the outlet passage. The poppetvalve is normally held closed by the valve spring,sealing the connecting passage from the pressurizedoutlet passage. The poppet valve, being a piston, isexposed to the pressurized hydraulic fluid in the outletpassage. Whenever the hydraulic pressure against thepoppet valve becomes greater than the pressure beingexerted on the poppet valve from the opposite
direction by the valve spring, the poppet valve willopen. This allows some of the pressurized hydraulicfluid to flow through the connecting passage to thenon pressurized inlet passage. The effect is to lowerthe pressure in the outlet passage which will allow thevalve spring to close the poppet valve again.
E-72 UNIT COMPONENTS
MOTOR (4-1/2”)
Monarch - Two terminal
The Monarch motor is a four pole, electromagnet motorwhich consists primarily of a 4-1/2" diameter solid steelframe, armature, brushes, field coils and pole pieces.This motor can be used on vehicles with either thecommon negative ground electrical system or thepositive ground electrical system.
HYDRAULIC PUMP
The pump in a hydraulic system employs an externalsource of power to apply a force to a liquid. A pumpdevelops no power of its own. It simply transfers powerfrom an external source (the electric motor on theE-72) to the liquid in the hydraulic system.
The basic operating principles of the hydraulic pumpused in the E-72 units are quite simple. Figure 1-5illustrates the basic components of a positivedisplacement gear type pump and their functions. Thepumping action takes place within the pump chamberwhich is connected to the reservoir by the intake line.The pump chamber has an outlet line in which the liquidunder motion and pressure leaves the pump to performwork.
“C” Solenoid Valve E-72
The “C” Solenoid valve is used on the E-72 hydraulicunit for power angling. The “C” Cartridge contains aspool valve whose static (de-energized) position allowsthe pressurized hydraulic fluid to flow to the right powerangling cylinder which angles the plow to the left. Atthe same time, it allows the hydraulic fluid being forcedfrom the retracting left power angling cylinder to flowthrough the “C” Cartridge back to the reservoir.
In the energized position, the pressurized hydraulicfluid is diverted to the left power angling cylinder,angling the plow to the right. Also, the hydraulic fluidbeing forced from the retracting right power anglingcylinder flows through the “C” Cartridge back to thereservoir.
CHECK VALVES
Check valves are very simple devices that have twobasic functions: They prevent fluid from passing throughthem in one direction, but they allow fluid to passthrough them in the opposite direction.
In the E-72 a pump check valve is used to preventhydraulic fluid from leaking back through the pump tothe reservoir.
The E-72 unit uses one check valve located betweenthe “B” Solenoid Valve and the lift cylinder. It preventsthe hydraulic fluid in the lift cylinder from leaking backthrough the “B” Solenoid Valve which could cause theplow to drift down.
DOUBLE ACTING PILOT CHECK VALVE
The pilot check valve is more sophisticated in that itincorporates a piston in addition to the ball, seat andspring. It is located next to the “C” valve on the E-72.It has two functions: The first is to prevent the hydraulicfluid in either power angling cylinder from leaking backto the reservoir. The second is to allow the hydraulicfluid from the retracting power angling cylinder duringthe angling cycle to return to the reservoir. This isaccomplished by the pressurized hydraulic fluidmoving the piston which forces the check ball off itsseat.
-11-
ELECTRO LIFT® UNIT COMPONENTS CONT.
The Coil is the electrical component which operatesthe Cartridge’s valve mechanism by producingmagnetism which pulls the Cartridge’s armaturetoward it. Since the armature is connected to thevalve mechanism’s only moving part, it is pulledby the armature.
Figure 1-7 illustrates the typical Coil. Wheneverelectrical current flows to the Coil, it flowsthrough the winding, which consists ofnumerous turns of copper wire. The flow ofcurrent through the winding produces amagnetic field which pulls the soft iron armaturefurther into the Coil.
The armature pulls the valve spool or poppetvalve into its alternate (energized) position. Notillustrated is an integral coil spring, which iscompressed when the armature is pulled by themagnetism.
When the current flow ceases, the magnetic fielddisappears and the compressed coil springpushes the armature back to its original(de-energized) position.
“A” Solenoid Valve E-72
The “A” Cartridge contains a poppet valve whose staticor de-energized position is closed. Its energizedposition is open.
The “A” Solenoid Valve retains hydraulic fluid in thelift cylinder. It is energized (opened) to allow thehydraulic fluid to flow from the lift cylinder back tothe reservoir, enabling the plow to lower by gravity.
The “A” Solenoid Valve is designed to remainenergized (open) while the plow is lowered, plowingsnow. This is the “float” feature which insures thatthe plow maintains contact with the ground contour.
“B” Solenoid Valve E-72
The “B” Cartridge contains a poppet valve whosestatic or de-energized position is closed. Its energizedposition is open.
The “B” Cartridge contains a spool valve whose(energized) position allows the pressurized hydraulicfluid to flow to the lift cylinder, raising the plow.
The “B” Cartridge de-energized position retains thehydraulic fluid in the lift cylinder, holding the plowup.
ELECTRO LIFT® UNIT COMPONENTS CONT.
CROSSOVER RELIEF VALVE
When plowing snow, a snow plow can be exposed todamaging forces caused by impact with hiddenobstructions, ends of curbs, etc. With power angling,these damaging forces can damage not only the snowplow but also the vehicle. The crossover relief valvehas the function of protecting the snow plow systemagainst these damaging forces under normal snowplowing conditions. The crossover relief valve, cannotprotect the system from damaging forces that are toogreat due to abusive snow plowing conditions.
Basically, the crossover relief valve functions exactlylike the previously described pump relief valve. It’sdesigned to open at a specific pressure.In this instance, the pressure is not produced bythe pump but rather by the damaging force. As anexample, assume that the right corner of the plowruns into the end of a curb. The impact will attemptto collapse the right power angling cylinder. As aresult, very high hydraulic pressure is producedwithin the cylinder. When the produced pressure ishigh enough, it opens the crossover relief valve,allowing the highly pressurized hydraulic fluid to flowdirectly to the left power angling cylinder.
When the crossover relief valve functions in this manner,the excessive pressure is released, the excessive energyproduced by the impact is absorbed, and the result isonly a change in angled position of the plow.
The crossover relief valve is factory set to the specifiedpressure of 3000 P.S.I. this setting is adjustable.
SOLENOID SWITCH
The E-72 motor requires more current or amperage tooperate than the vehicle wiring, vehicle ignition switchor toggle switches have the capacity to handle. Thesolenoid switch is essentially a heavy duty switch withthe capacity to handle the heavy current required bythe motor. It is closed electrically by the solenoid toconvey the heavy current directly from the vehiclebattery via heavy gauge electrical cable. The solenoid,which functions essentially the same as the previouslydescribed solenoid valves, receives its low amperagecurrent at the proper times via the wiring harness. Thissolenoid must be grounded to operate properly.
STRAINER
Cleanliness is perhaps the single most importantingredient in assuring a hydraulic system’s reliability.Should the hydraulic fluid become contaminated,malfunction and permanent damage to the hydraulicsystem may occur. For this reason, all the E-72 unitsare equipped with a Strainer on the pump pick uptube.
-12-
With this system, the hydraulic fluid is filtered as itleaves the reservoir on its way to the pump and on thePower Angling units.
IMPORTANT:
Should the hydraulic fluid become contaminated, itwill be necessary to replace all the hydraulic oil in thesystem. The complete system (hydraulic unit, powerangling cylinders, mount cylinder and hoses) shouldbe flushed. Flush the system with Meyer Hydra-Flush™Fluid M-2.
-13-
SECTION 2 - DIAGNOSIS
CONTENTS
E-72
GENERAL INFORMATION 14
TESTING TIPS 14
“RAISE” Troubleshooting 15
“LEAK DOWN” Troubleshooting 16
“LOWER” Troubleshooting 16
“ANGLE LEFT” Troubleshooting 17
“ANGLE RIGHT” Troubleshooting 18
“WILL NOT HOLD ANGLE” Troubleshooting 18
Wiring Information 19
-14-
DIAGNOSTIC FLOW CHART FORE-72 Unit
These charts are intended to be used as an aid in diagnosing problems on the E-72 unit. They are not a substitute for factory training andexperience. Be certain to read the General Information and Testing Tips sections before attempting any troubleshooting.
IMPORTANT: Maintenance and repairs must be performed with the moldboard on the ground.
General InformationBefore any troubleshooting is started, make certain the following conditions are met.
1. The moldboard is pointing straight ahead. This can often be done by coupling the left cylinder into the right cylinder andpushing the moldboard by hand.
2. The power angling cylinders must be installed correctly on to the plow assembly. The left cylinder (Driver’s side) has a hoseattached with a female half of a coupler at the end; the right cylinder (Passenger side) has a hose attached with a male halfof a coupler at the end.
3. The solenoid wires must be on their proper coil. The “A” coil (black and tan wires) on power angling block labeled “BLK”. The“B” coil (red and tan wires) on power angling block labeled “RED”. The “C” coil (green and tan wires) on power anglingblock labeled “GRN”.
TESTING TIPS
Many tests do not require removing the Electro Lift® unit from the vehicle. However, more thorough testing can beperformed using the Meyer Test Stand which allows direct pressure and amperage readings.
1. Using a screwdriver or other small tool to check for magnetism of the solenoid coils “A”, “B” and “C”. Place the tool on the nutsecuring the coil and have an assistant operate the switch. You should feel strong magnetic attraction.
2. Use a test light or volt meter to determine whether there is power at the harness.3. When determining AMP draw of the motor, always obtain the highest value possible, i.e, at maximum raise or maximum
angle with motor running.4. The pump shaft of a good pump can be turned smoothly using two fingers. If it can’t be turn easily, the pump is too tight and must
be replaced.5. Pump pressure can be measured at an angle hose (note pressure at full angle).6. Flush the complete system including unit, hoses and power angling rams with Meyer Hydra-Flush™ Fluid M-2.
The controller is self diagnosing. The monitor light is located in the upper left corner next to the float light of the control switch. When themonitor light turns on and begins to flash the control switch is sensing a problem with a specific coil/connection on the hydraulic unit.The label below is on the back side of your control switch. Reset is accomplished by turning off the ignition switch or by turning thepower switch off momentarily and then back on. If the monitor light is still illuminated after attempts to reset the switch have failed,contact your nearest authorized Meyer Distributor for repairs.
-15-
E-72SNOW PLOW WILL NOT RAISE
Does the MotorOperate?
Is there power going to the motor?
Are all electricalconnections clean and tight?Is Battery Charged?
Charge Battery -Clean and tighten all electrical Connections.
Remove motor.Does motor run when 12 volts is applied?
Inspect Motor -Armature, BrushesRepair or ReplaceMotor as necessary
Is there power going to the motor solenoid,at White Wire?
Is there power leaving the switch? Check switch for Continuity
Check Wires atMolded connector.
Can the pump shaft turn by hand?
Replace pump.
Replace the Motor Solenoid.
Replace the Wiring Harness.
Is the Fuse OK?
Is Ground Cable attached to the Negative (-)Battery Terminal?
Replace the
Controller
Does the snow plow angle to the left instead of raising?
Does the snow plow angle when the Angle Switch is activated?
Is there pressure (or flow) at the raise port?
Is the "A" Valve stuck in the open position?
Clean or Replace "A" Valve. -Retest - Does snow plow raise?
Can pump relief pressure be adjusted
to 2000 P.S.I.
Replace the Pump.
Is the pump shaft turning tightly?
Does the motor armature turn tightly?
Replace the Pump.
Repair or Replace the motor.
Replace Fuse.Check for short in Harness, "B" Coil, Switch Connections,Motor Solenoid,Electric Motor.
NONO
NO NO
NO
NO NO
NO
NO
NO NO NO
NO
NO NO
NONONO
NO
YES
YES
YES
YES
YES
YES YES YES
YES
YES
YES
YES
YESYES
YES
YES
YES YES YES
YESYES
Does the "B" Coil (Red Wire) have magnetism?
Are the "B" Valve O-Rings in good Condition?
Replace O-Rings.
Clean orReplace the "B" Valve and retest.
Is there power to the "B" Coil? (Red Wire) at Harness
Is there powerleaving the switch at the red wire?
Replace "B" Coil.
Replace the wiringharness.
ReplaceController
Are wires inmolded connectormaking contactwith the switch?
Is the fluid level 1-1/2" below filler hole?
ADD M-1 Fluid
E-72
-16-
SNOW PLOW LEAKS DOWN
Does thesnow plow drop straight down?
Does the snow plow drop and angle to the left?
NO
NOYES
YES
NO
NONONO
SNOW PLOW WILL NOT LOWER
NONO
YES YES YES
NO
Replace "B" Check ValveDoes it now hold?
Replace "B" Valve
Are "A" Valve O-rings in good condition?Does "A" Valve stem move freely?
Replace O-RingsReplace "A" Valve
Does "A" Coil(Black Wire) have magnetism?
Replace "A" ValveDoes it now lower?
Is there power to the"A" Coil (Black Wire) at harness?
Is there power leaving the switch at the Black Wire?
Is the Controller plugged in completely?
Replace"A" Coil
Check for a clogged filter or a blocked passageway.(Lower Adj. Screw)
Check for Bent or Siezed Ram Assembly.
Replace Controller
ReplaceHarness
Is Fuse OK?
YES
Replace the fuse -Check for short inharness, "A" Coil, Plug connections.
YES
YES
Replace Lift Cylinder
E-72
-17-
SNOW PLOW WILL NOT ANGLE LEFT
Can the snow plow Raise?
See the Raise Flow Chart Section
NO
NONO
YES YES YES
Is there power tothe motor solenoid? (White Wire)
Is there power leaving the switch?
Is the switchplugged in completely
Are "C" ValveO-Rings in good condition?
Replace Piston
Weld1-1/2" x 1-1/2" x 1/2"spacers to the A-Frame stops.
ReplaceO-Rings
YES
Will the snow plow angleright & left if not allowed to travel to extreme angled position?
YES
Does the motor run when angle switch is pushed?
NO
Replace HarnessReplace controller
NONODoes the snow plow angle to the right the angle left switch is pushed?
Is the ampere drawless than 100 ampswhile trying to angle snow plow?
Can the snow plow be angled by hand when the
P.A. Rams are disconnected from A-Frame?
Does the snow plow raise instead of angling left?
NO
NO
Relieve the interference between the Sector and A-Frame.
NOClean or replace the "C" Valve. Retest
Is the Pilot piston in good condition?(worn/sloppy or missing)
Clean or replace the "B" Valve. Retest
Does pressure remain in angle hose
when the motor is not running?
NO
NO
YESYES
YES
NOTemporarily put 1/2" blocksbetween the Sector andA-Frame to limit the degree of angle. Will the snow plownow angle?
Clean or replace the "C" Valve.
If both hoses are stiffinspect the Pilot Check Piston and "C" Valve for binding.
If one hose is stiff inspect the the "C" valve for binding.
Clean or replacethe Crossover Relief.
YES YES
YES
YES
NO
YES
E-72
-18-
Clean or replace the "C" Valve.
SNOW PLOW WILL NOT ANGLE RIGHT
Can the snow plow Raise?
See the Raise Flow Chart Section
NO
NONO
YES YES
Is there power tothe motor solenoid? (White Wire)
Is there power leaving the switch?
Are the wires inmolded connector making contact with the switch?
Are "C" ValveO-Rings in good condition?
Replace the "C" Coil. Retest
ReplaceO-Rings
YES
Does the motor run when angle switch is pushed?
NO
Replace HarnessReplace
Controller
Can the snow plowangle to the Left?
Does the snow plow raise instead of angling left?
NO
NODoes the "C" Coilhave magnetism? (Green Wire)
Is there power to the "C" Coil?(Green wire at harness)
Clean or replace the "B" Valve. Retest
NO
YES
Clean or replacethe Crossover Relief.Does the snow plow now angle?
YES YES
YES
NO NO Is there power leaving the switch?
Are the wires inmolded connector making contact with the switch?
YES
Replace Harness
YES
YES
YES Replace Controller
SNOW PLOW WILL NOT HOLD ANGLE
Bleed air from the system and snug up gland nuts. Check fittings for leaks.
NONODoes the moldboard hold left angle & release from right angle?
Are the Rams mushy?Can you push the moldboard 6" to 8" by hand?
NO
NO Change Pilot Check
does snowplow now hold?
Inspect Crossover Relief. (Rebuild or Replace)
YES
YES
Replace Crossover.
Change Pilot Check
does snowplow now hold?
-19-
E-72 Wiring
BATTE
RYPO
S
NEG
Black Ground
Red
"A" LightAdapter
"B" HarnessPower/Ground Park &Turn
"C" HarnessTo Plow Light
"A" "B"
"C"
WhiteBlack Blue (Reverse
Signal)
Orange to "B"harness of light modules
See page 38 for diode wiring on motor solenoid
"A" Black Wire"B" Red Wire
"C" Green Wire
Lift Cylinder
Passenger Side (RH)
Driver Side (LH)
-20-
SECTION 3 - REPAIR PROCEDURES
CONTENTS
GENERAL INFORMATION ........................................... 21
UNIT DISASSEMBLY AND REASSEMBLY ................. 21
Disassembly ............................................................. 21
Reassembly .............................................................. 21
• Additional Reassembly Points ............................ 21
PUMP............................................................................... 21
Shaft Seal Replacement ......................................... 21
E-72 ELECTRO LIFT® .........................................................................................
Exploded View ......................................................... 22
Parts Breakdown ..................................................... 23
Disassembly Photos ................................................ 24-33
Reassembly Photos ................................................. 34-37
CONTROLLER OPERATION........................................ 38
SPECIFICATIONS ......................................................... 39
-21-
GENERAL INFORMATION
Using the proper guidelines and precautions, theE-72 units are easy to disassemble and reassemble.Figure 3-1 is an exploded view which applies to theE-72. It should be used as the primary reference forproper reassembly. Where necessary, this sectionincludes additional information, photographs andillustrations to assure proper and efficient repairs.
UNIT DISASSEMBLY AND REASSEMBLY
Many repair procedures, including removal andreplacement of the “A”, “B” and “C” Solenoid Valves,can be accomplished without removing the unit fromthe vehicle. While Figures 3-2 through 3-76 show theunit clamped in a vise, make all possible repairs onthe vehicle when possible.
NOTE: Pump Assembly should not be disassembledsince it cannot be serviced.
Disassembly
See Figures 3-2 through 3-45 (pages 24-34).
Reassembly
See Figures 3-46 through 3-76 (pages 35-42) forimportant reassembly points.
Additional Reassembly Points
O-Rings- Coat liberally with hydraulic fluid andposition carefully to minimize possibilityof damage during assembly.
Fasteners- Torque all fasteners which are specified toinsure proper reliability and preventdamage due to over-tightening.
PUMP
Shaft Seal Replacement
NOTE: Do not disassemble pump assembly.
1. Remove motor and Pump assembliesas shown inFigures 3-31 thru 3-44 (pages 31-34).
2. Using an appropriate tool, pry out the original shaftseal, being careful not to damage the shaft or pumphousing.
3. Liberally coat the replacement seal I.D. withhydraulic fluid and apply a very light film ofPermatex Form-A-Gasket No. 2 or equivalent tothe replacement seal O.D.
4. Carefully slide the replacement sealover the shaft until it is squarely against the pumphousing.
5. Replace the motor and pump assemblies asshown in Figures 3-47 & 3-55 (page 35-37).
-22-
FIGURE 3-1
E-72Exploded View
1
2
3
45
6
7
8
9
10
11
12
13
15
1617 18
19
20
2122
23
13
13
14
14
23
-23-
PARTS BREAKDOWN
PARTS LIST
Parts indented are included in assembly under which they are indented.
ITEM E-72 12V E-72 24V QTY DESCRIPTION16006 16007 1 Lift Assembly (Unit Only)
1 15096 15154 1 • Motor (2 Terminal)2 15097 15097 1 • Pump Assembly3 15083 15083 4 • Allen Head Screw 1/4-20 x 3"4 15101 15101 1 • Pump Filter Assy.5 15169 15169 1 • Reservoir6 15066 15069 1 • Reservoir Clamp7 15067 15067 1 • Reservoir Breather8 15100 15100 1 • Oil Pick up Tube 5-3/4"9 15099 15099 1 • Oil Return Tube 8"
10 15180 15180 1 • Oil Return Tube 8"11 15175 15170 1 • Base Assembly12 15121 15121 1 • Adjustable Relief Valve13 15082 15082 1 • Seal Kit (All Seals)14 15150 15157 3 • Coil (12V)15 15146 15146 1 • "A" Cartridge Valve16 15117 15117 1 • "B" Cartridge Valve17 15111 15111 1 • "C" Cartridge Valve18 15165 15165 1 • Kit Needle Valve (Lower Adj.)19 15148 15148 1 • Kit Dual PO Check Valve20 15152 15152 1 • Kit Check Valve Assembly21 15179 15179 1 • Kit Relief Valve Assy. 3000 p.s.i.22 22866 22866 1 • 90 degree elbow fitting23 22868 22868 2 • Straight Fitting
DISASSEMBLY
FIGURE 3-2To drain oil from the unit, remove the fill plug and drainplug.
-24-
FIGURE 3-3Use a 3/4” wrench to loosen and remove “A” Coil.
FIGURE 3-4Remove “A” Coil.
FIGURE 3-5Use a 7/8” wrench to loosen and remove “A” Valve.
DISASSEMBLY
-25-
FIGURE 3-6Remove “A” Valve. Clean by soaking cartridge in cleaningsolvent.
FIGURE 3-7Use a 3/4” wrench to loosen and remove “B” Coil.
FIGURE 3-8Remove “B” Coil.
FIGURE 3-9Use a 7/8” wrench to loosen and remove “B” Valve.
DISASSEMBLY
-26-
FIGURE 3-10The “B” Cartridge is removed. Clean by soakingcartridge in cleaning solvent.
FIGURE 3-11Use a 3/4” wrench to loosen and remove “C” Coil.
FIGURE 3-12Remove “C” Coil.
FIGURE 3-13Use a 7/8” wrench to loosen and remove “C” Valve.
DISASSEMBLY
-27-
FIGURE 3-14The “C” Cartridge is removed. Clean by soakingcartridge in cleaning solvent.
FIGURE 3-15Use a 11/16” wrench to remove the Lower AdjustmentAssembly.
FIGURE 3-16Remove Lower Adjustment Assembly.
FIGURE 3-17Remove hydraulic Breather.
DISASSEMBLY
-28-
FIGURE 3-18Use a 7/8” wrench or socket to loosen and remove PilotCheck Valve Assembly.
FIGURE 3-19Remove Pilot Check Valve Assembly. Clean by soakingAssembly in cleaning solvent. Do not take apart.
FIGURE 3-20Use a 7/8” wrench to loosen and remove Cross-overRelief Valve. The Cross-over Relief Valve is factory setat 3000 P.S.I. It is adjustable by removing the cap andinserting an allen wrench to turn clockwise to raise thepressure and counter clockwise to lower the pressure.
FIGURE 3-21Remove Cross-over Relief Valve.
DISASSEMBLY
-29-
FIGURE 3-22Use a allen wrench to loosen and remove “B” checkvalve plug.
FIGURE 3-23Remove “B Check Valve plug.
FIGURE 3-24Remove “B Check Valve spring.
FIGURE 3-25Remove “B Check Valve poppet.
FIGURE 3-27Loosen and remove pump pressure relief valve with anallen wrench.
DISASSEMBLY
-30-
FIGURE 3-28Remove pump pressure relief valve adjuster.
FIGURE 3-29Remove pump pressure relief valve spring.
FIGURE 3-26Loosen jam nut on pump pressure relief valve.
DISASSEMBLY
-31-
FIGURE 3-30Remove pump pressure relief valveball.
FIGURE 3-33Use a screwdriver to loosen reservoir clamp and removeclamp.
FIGURE 3-31To replace the motor remove the two cap screws, use a7/16” wrench.
FIGURE 3-32Hold the motor parts together while removing it from thepump base.
FIGURE 3-34Remove Reservoir from Base. Clean reservoir with hotsoap and water.
FIGURE 3-35Carefully loosen and remove plastic oil return tubes.
DISASSEMBLY
-32-
FIGURE 3-37Slide Strainer off pump pick up tube.
FIGURE 3-36Remove plastic oil return tubes.
-33-
DISASSEMBLY
FIGURE 3-39Remove plastic oil pick up tube.
FIGURE 3-38Carefully loosen and remove plastic oil pick up tube.
FIGURE 3-40Use an allen wrench to loosen and remove the 4 boltsholding the pump to the base.
FIGURE 3-41Remove the 4 bolts holding the pump to the base.
FIGURE 3-43Clean base with cleaning solvents and inspect pumpshaft bearing. If bad replace the base.
FIGURE 3-42Remove pump from base.
-34-
FIGURE 3-45Meyer E-72 Seal kit 15170.
FIGURE 3-44Remove pump shaft seal from opposite side of baseand replace.
DISASSEMBLY
Beforereassembly, be
sure to haveMeyer seal kitpart number
15170
-35-
REASSEMBLY
FIGURE 3-47Attach pump to base with 4 allen head bolts.
FIGURE 3-46Replace pump to base o-ring and re-install pump.
FIGURE 3-48 FIGURE 3-49Re-install oil pick-up tube to pump. Do not overtightenor use any thread sealant.
Torque all four pump mounting bolts to 100-125 in. lbs.be sure to torque in an even pattern.
FIGURE 3-50Slide strainer onto plastic oil pick-up tube. Do not glue,this will be held in place by the reservoir.
FIGURE 3-51Re-attch both platic oil return tubes to the base. Do notuse thread sealant and do not over tighten.
-36-
REASSEMBLY
FIGURE 3-52Replace o-ring on base and install reservoir.
FIGURE 3-53Clamp reservoir to base with reservoir clamp. Do notuse sealant.
-37-
REASSEMBLY
FIGURE 3-54Carefully re-install motor to base. Be sure motor shaftaligns with pump shaft.
FIGURE 3-55Tighten motor mounting bolts to base using a 7/16”wrench.
FIGURE 3-56Re-install pump relief valve ball.
FIGURE 3-57Re-install pump relief valve spring.
FIGURE 3-58Install pump relive valve adjuster. This will be adjustedwhen hydraulic unit is back on plow. Put a guage in anangle hose and extend the angle hose all the way, whileholding the button for angle set pressure to 2000 P.S.I.(tighten increases and lossening decreases pressure).
FIGURE 3-59Tighten adjuster jam nut after pressure has been set to2000 P.S.I.
-38-
REASSEMBLY
FIGURE 3-60Install “B” Check Valve Poppet.
FIGURE 3-61Install “B” Check Valve Spring.
-39-
REASSEMBLY
FIGURE 3-62Install “B” Check Valve Cap.
FIGURE 3-63Tighten “B” Check Valve Cap.
FIGURE 3-64Re-install Cross-over relief valve. Tighten Cross-overrelief valve. Pressure is adjustable and should be set to3000 PSI. In order to adjust set a guage in agle ram andapply pressure to angle system at plow.
FIGURE 3-65Turn in allen screw to raise and out to lower pressure.Valve should open when 3000 PSI is attained and allowsthe plow to angle. This valve enables the plow to absorbimpacts.
FIGURE 3-66Re-install Pilot Check Valve Assembly.
FIGURE 3-67Tighten Pilot Check Valve Assembly.
-40-
REASSEMBLY
FIGURE 3-68Re-install Breather
FIGURE 3-69Re-install Lower Adjustment Assembly. To adjust dropspeed of the plow turn the knob in for slower and out forfaster drop.
-41-
REASSEMBLY
FIGURE 3-70Re-install “C” Valve
FIGURE 3-71Re-install “C” Coil.
FIGURE 3-72Re-install “B” Valve.
FIGURE 3-73Re-install “B” Coil.
FIGURE 3-74Re-install “A” Valve.
FIGURE 3-75Re-install “A” Coil.
-42-
REASSEMBLY
FIGURE 3-76Fill Hydraulic Unit with Meyer M-1 Fluid. Flush out hoses,lift cylinder and both angle cylinders before operatingplow.
-43-
SNOW PLOW CONTROLLER OPERATION
The snow plow should only be in operation when the vehicle ignition switch and the control switch are in the “ON” position. Care should be taken toinsure that the control switch is kept dry and free from moisture during normal operation.
When the control switch is turned “On,” lights illuminate the location of the individual touch pads for the functions of the snow plow: (Up), (Angle Left),(Angle Right) and (Down).
Lowering of the snow plow an inch at a time is possible by tapping the down arrow in short intervals. Holding down the down arrow will activate a floatlight located in the upper right corner of the control switch. This light indicates the snow plow is now in the Lower/Float position. In this position thesnow plow will be able to follow the contour of the road and the snow plow can also be angled to the left or right. Touching the up arrow automaticallycancels the Lower/Float position.
While angling left or right or raising the snow plow if the button is pressed for more than four seconds the operation will be cancelled. This featureeliminates unnecessary amp draw from the vehicle charging system.
Hands-Free Plowing or ALM/ARMMeyer re-branded the ALM/ARM feature on its 22690X controllers to be Hands-Free Plowing (HFP) ™. When activated, theHands-Free Plowing (HFP) mode uses the vehicle’s shift lever to control the up/down movement of the moldboard. Pressing theHFP button on the controller will toggle you through: On/Off, Back-drag Mode (default mode when active), and Forward PlowingMode.Back-dragging Mode or ALMWhen the controller is on and you are in the conventional plow control mode, pressing the HFP button will activate Hands-FreePlowing (HFP). The default mode for HFP is the Back-drag Mode. In the Back-drag Mode, the moldboard will automatically lowerwhen you put the vehicle in reverse. Put the vehicle in drive to automatically raise the moldboard.Forward Plowing Mode or ARMTo activate the Forward Plowing Mode when HFP is already on, press the HFP button once. The moldboard will automatically lowerwhen you put the truck into drive. When you reach the end of a run, the moldboard will automatically raise when you put the vehiclein reverse.To turn the HFP feature off, press the HFP button until you see the HFP light go off.
This switch is self diagnosing. The monitor light is located in the upper left corner next to the float light of the control switch. When the monitor lightturns on and begins to flash the control switch is sensing a problem with a specific coil/connection on the hydraulic unit. The label below is on the backside of your control switch.
Reset is accomplished by turning off the ignition switch or by turning the power switch off momentarily and then back on. If the monitor light is stillilluminated after attempts to reset the switch have failed, contact your nearest authorized Meyer Distributor for repairs.
INSTALLATION INSTRUCTIONSWhen installing motor solenoid part number 15370 (per form number 1-841) or If motor solenoid is already installed on the vehicle, the enclosed diode partnumber 15059, must be connected to the small terminal with white wire of the motor solenoid and to the motor solenoid mounting bracket as shown below.Note: Motor Solenoid must have a good ground in order to operate properly. The 22717 control adapter shown below is only needed when replacinga 22154 Touchpad. The orange wire of the adapter can be connected to the orange wire on the back of the plow light switch. The plow light switch couldthen be removed along with the black and red wires which were connected to the plow light switch. When the controller is turned on it will activate the snowplow lights. When the controller is turned off or removed from the harness this will activate the vehicle headlights.
Blue wire toreverse signal.
To 22690X Controller
To vehicle harness
To orange wire fromplow light switch.
22717 Adapter
On/Off
Float
Monitor
Angle Right
Angle Left
Raise
Lower
Systems MonitorLED Read-Out
Light Flashes Check Coil (wire Color)
Continuous Light----Motor Solenoid1 Light Flash----Red
2 Light Flashes----Black3 Light Flashes----Green4 Light Flashes----Yellow
5 Light Flashes----Lt. Blue6 Light Flashes----Purple
4 Post Motor Solenoid
3 Post Motor Solenoid Imprinted on backside of Controller
HFP (ALM/ARM)
ELECTRICAL SPECIFICATIONSMOTOR
Applied Voltage 12 Volts DCMax. Current Draw 230 Amperes
SOLENOID VALVES “A”, “B” and “C”Applied Voltage 12 Volts DCCurrent Draw 1.9 AmperesNominal resistance (ohm meter lead connectedto coil lead) 8.0 ohms ± 10%.
MOTOR SOLENOIDApplied Voltage 12 Volts DCMax. Current Draw 5 Amperes
Nominal resistance (ohm meter lead connected tocoil lead, other meter lead connected to metalfoot) 2.65 to 4.5 ohms.
HYDRAULIC SPECIFICATIONS
PUMP - Pressure Output 2000 P.S.I.
CROSSOVER RELIEF VALVEOpening Pressure 3000 P.S.I.
HYDRAULIC FLUID CAPACITYNOTE :1 Quart = 32 Fluid OuncesModel E-72Unit 1 qt., 4.5 oz.
(36.5 oz.)Hoses & 1-1/2 x 10 Cylinders 16 oz.Total 1 qt., 20.5 oz.
(52.5 oz.)
HYDRAULIC SPECIFICATIONS
-44-
-45-
Notes
E-72power unit
service manual
© 2012 Printed in the U.S.A.
Meyer Products LLC18513 Euclid Ave. • Cleveland, Ohio 44112-1084
Phone 486-1313 (Area Code 216)www.meyerproducts.com• email [email protected]