Advance Lifts Dock Lifts 6000 Series Manual

							 
 
SECTION 7.  POWER UNIT ASSEMBLIES 
 
This section contains drawings and photos of completed power units to aid service 
personnel in identifying each component.  Please be careful to match the correct 
voltage and horsepower as well as model number, when you are trying to identify the 
power unit for your lift.  Advance Lifts uses several different brand name motors and 
pumps, so the ones shown in the pictures may not be the same exact brands as on your 
unit.  More information about individual components may be available in the hydraulic or 
electrical sections of this manual.  Also note that these illustrations may show options 
that were not included on your particular unit and the components used may be 
changed at any time without notice. 
 
6000 SERIES 
Power Unit* 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
See Page 8-4 for Hydraulic Diagram and Pages 9-3, 9-4 for Electrical Diagram 
 
*FOR REFERENCE ONLY 
 
P 7-1 
 
Reservoir Breather Cap Discharge Line 
Motor Pump Control Box Overload Reset Button 
Junction Box 
(Not Shown)  
						

							 
 
SECTION 8.  HYDRAULIC DETAILS 
  
1. General Hydraulic Information:  
A.  All hydraulic cylinders will require the replacement of packing’s and seals after a 
period of time, depending on usage and environmental conditions.  It is normal 
maintenance just like changing oil in an automotive engine.  However, 
maintenance personnel should recognize the difference between leakage and 
weepage: 
B.  Weepage is the normal accumulation of fluid that passes the seals in the course 
of operations, as the hydraulic fluid properly performs its lubrication function on 
cylinder walls and piston rods.  It may be occasionally observed squirting from 
cylinder breathers, but should stop squirting after several cycles of full stroke 
when the small accumulation is cleared. 
C.  Leakage is the fluid that leaks past worn or cut packing’s and seals.  It too may 
be observed squirting but does not stop after several cycles and the lift will 
probably not hold position under load. 
D.  See repacking under cylinder repair procedures. 
E.  Always be careful when working around cylinders, not to nick the extended rod or 
dent the cylinder casing, as this may cause damage to cylinder seals or 
packing’s. 
F.  If you elect to repaint or retouch part of the lift, cover exposed rods with plastic or 
soluble grease that can be removed after painting to insure that no paint sticks to 
the rods and damages packing’s or seals. 
 
2. General precautions: 
A.  Be sure that all pressure is relieved from the hydraulic system before 
disassembling any components.  Continue to hold the down button for several 
seconds after fully lowering the unit on its maintenance device or the ground, 
before opening a line or component. 
B.  Always be careful to avoid contamination entering the system.  Be especially 
careful with the ends of hoses that may fall into oil dry or dirt.  If you suspect 
contamination, flush the system and components. 
 
3. Hydraulic fitting sealant and torque: 
A.  Advance lifts may be equipped with either NPT fittings (tapered) or SAE fittings 
(with “O” ring seals, depending on age, know the difference! 
B.  Be careful when tightening NPT fittings not to over tighten and crack them.  
Swivel fittings are especially vulnerable and should only be snug enough to stop 
leaking. 
C.  If leakage persists after tightening the fittings fairly hard, inspect fittings for burrs 
on the mating edges or the possibility of a 37 degree SAE fitting being mixed with 
the standard 30 degree NPT fittings, or either one being mixed with SAE 45 
degree fittings. 
D.  When using Teflon tape on NPT fittings, be sure the tape is started 1-1/2 threads 
back from the leading edge and only use 2 wraps to be sure that tape does not 
break off and contaminate the system.  You may substitute pipe sealant with 
Teflon paste from Pro Lock or Locktite, but again don’t over apply.  Never use 
sealant or tapes on swivel
 fittings or SAE o-ring fittings. 
E.  Never reuse old Teflon tape.  Once a connection has been opened, remove all 
old tape and apply fresh tape. 
 
P 8-1 
						

							 
 
 
Oil Recommendations & Seal Compatibility 
 
Fluids: 
 
1.  The current standard hydraulic fluid an ISO 46, (group II base) hydraulic fluid. This is 
the fluid normally supplied by the factory and is suitable for a temperature range of –
10 to +100 degrees Fahrenheit. When replacing or adding fluid to an Advance Lift, 
use only ISO 46 hydraulic fluid that is manufactured with a group II base oil. ISO 46 
hydraulic fluid can be identified by its purple color. 
 
2. Caution! Do not use any fluid that has not been approved by the Advance Lifts 
engineering department.  Brake fluids and other hydraulic fluids may attack the 
system’s seals or hoses. 
 
3.  A biodegradable or fire resistant fluid is also available, however you must contact the 
factory for its name, because it is also necessary to change some seals and/or 
hoses for total system compatibility, depending upon the specific model lift that you 
have. 
 
Seals: 
 
Generally, the seals in the unit are Buna-N-Nitrile and polyurethane.  The hoses are 
composed of either PVC for suction lines or braided wire.  Always call the factory about 
special fluids rather than make assumptions on your own. 
 
Options: 
 
1.  For extremely cold applications we recommend an oil immersion heater which 
simply fits in the drain coupling on most units, replacing the drain plug, these are 
available in appropriate sizes from the factory. NOTE: A separate 120V, 20 Amp 
circuit is required for all oil immersion heaters. 
 
2.  For extremely warm temperature ranges over +100 degrees Fahrenheit consult the 
factory. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
P 8-2 
						

							 
 
Pressure Chart for Hoses & Pipes 
 
     Hose        SAE        Working PSI      Bursting PSI 
           ¼”        100-R2A       5000           20000 
       
3/8”       100-R2A       4000           16000 
          ½”        100-R2A       3500           14000 
          ¾”        100-12        4000           16000 
 
 
           Seamless Pipe         Working PSI     Bursting PSI 
 
           ½” Schedule 80         4100                21000 
            ¾” Schedule 80        3500           17600 
          1” Schedule 80         3500          15900 
 
Caution: Never use any hose or piping that does not meet or exceed the ratings listed 
above. 
 
Line Size Calculations 
 
   Formula:  P=          V x Q                        Where: P=PSI loss per foot  
                                 18,300 x DxDxDxD                                        Q=GPM flow 
                                       V=SUS viscosity @ 
                                       Operating temp. 
                                       D=Inside dia. Of pipe 
                                       in inches 
 
 
Standard Oil Capacities of Listed Equipment  
   
2 – Cylinder units, 5 Gallons 
4 – Cylinder units, 7 Gallons 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
P 8-3 
 
  
						

							 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
     
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
P 8-4 
 
 
MOTOR  
PUMP SUCTION 
FILTER (IN 
RESERVOIR) 
Check Valves 4 Cylinder 
Units 
2 Cylinder 
Units 
Down Solenoid 
Relief Valve preset at 
factory (DO NOT 
ADJUST) Reservoir 
Flow Control 
Valve  
						

							P 8-5  
						

							 
 
 
Repair Procedures for Cylinders 
 
 
 Tools & Supplies Required: 
 
(2) Small screwdrivers to remove retaining rings and rod wipers. 
A clean (5) gallon bucket to collect fluid from the cylinders. 
Wrenches to disconnect hydraulic fittings. 
Cylinder hone (Craftsman glaze breaker #9K4633 or equivalent). 
Emery cloth 
Clean lint free cloths and hose caps. 
Clean work surface (butcher paper on top of most surfaces works well), with a 
means of holding cylinder end fixed position for disassembly and assembly.  
“Lubriplate Grease” and hydraulic fluid matching the existing fluid in the system 
for topping off when finished. 
Maintenance device, supplied with each Advance unit. 
 
Cylinder Removal: 
 
1.  Raise the empty lift and settle it securely on its maintenance device. 
2.  Once settled securely, depress the down button an additional 20 seconds to relieve 
any pressure from the cylinders.  Remove the power connection to the power unit 
and mark with a warning label or lock the connection out to prevent unintended 
reconnection. 
3.  Disconnect the hydraulic hoses from the cylinders, from below the deck. 
4.  Remove the retaining clips from the lower cylinder pin, then remove pin. 
5.  Thread a 3/8” I-bolt into the hole provided at the top of the cylinder and secure to a 
forklift or overhead crane. Once holding pressure is applied, remove the upper pin.  
6.  Cylinder is lifted up and out of the housing.   
7.  Place the hose connection end of the cylinder in a 5-gallon bucket and force the 
cylinder closed to drain the hydraulic fluid from the cylinder.  Do not reuse the fluid 
unless you are sure it is contamination free by careful straining. 
8.  Note that if you are going to repack one cylinder on a lift, it is usually a good idea to 
do all cylinders at the same time.  Packing’s generally wear at the same rate and if 
you only repack one cylinder, you may have to pull the lift out of service soon 
thereafter to do the others. 
9.  To install cylinder, reverse steps 6-3 
 
Cylinder Disassembly: 
 
1.  Secure the cylinder with a rod through the clevis or cross tube, do not use a vise, 
which will crush or otherwise damage the housing. 
2.  Using screwdrivers remove the spiral type retaining ring in front of the cylinder 
bearings.   
 
 
 
 
 
 
 
P 8-6 
 
  
						

							 
 
 
 
Cylinder Disassembly: (Continued) 
 
3.  Carefully remove any debris from the retaining grooves, and then pull out the entire 
rod, bearing, & piston assembly.  Note that the groove in the cylinder housing has a 
sharp edge on the front side and a beveled back edge.  The sharp edge is 
necessary for proper snap ring retention and will probably cut the packing when it is 
pulled out, but the beveled back edge will allow the new packing to slide in uncut.
 
4.  Remove the hex nut or snap ring adjacent to the piston, then slide the piston and 
bearing off of the rod.  If the hex nut is assembled with Locktite, a small amount of 
heat may help break the nut loose.  Be sure that all components are placed on clean 
surfaces to avoid contamination. 
 
Repacking and Inspection:  
1.  Carefully inspect the entire housing with a flashlight, looking for any evidence of rust, 
scratches, or surface blemishes.  Small blemishes may be removed with fine emery 
cloth and larger faults will require the use of the hone listed above.  Be sure to 
thoroughly clean the housing when you are done to avoid contamination. 
2.  Do not become the victim of a false economy by using only part of a repacking kit.  
Since you have invested in disassembling the cylinder, use all new packing parts 
and seals of the reused old parts may fail in the near future causing a repeat of the 
whole exercise. 
3.  Remove the rod wiper on the bearing by using a screwdriver to bend the seal inward 
to collapse and remove it. Inspect the groove and remove any debris. 
4.  Lubricate and insert a new wiper with your fingers, sliding it into its groove.  
Depending upon temperature, the rod wiper may slide in much easier if it is warmed 
in hot water, then dried, lubricated, and inserted.  The bearing may now be slid back 
onto the rod. 
5.  Begin repacking the piston by using a screwdriver to carefully remove the old 
backup rings and seal from the groove.  Newer cylinders are also equipped with a 
wear ring that should be removed at this time.  Be careful to leave the grooves nick 
free and clean. 
6.  Lubricate the new backup rings, seal and wear ring and gently stretch them into 
place.  Note that the seal fits between the rings. 
7.  Inspect the static seal groove on the cylinder rod, then lubricate the groove and slide 
a new static seal in place.  Slide the piston back into position noting that the flat side, 
not the chamfered side, should rest against the retaining ring or nut.  Reinstall the 
retaining ring or nut using Locktite if the fastener is a plain nut. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
P 8-7 
 
  
						

							 
 
 
 
 
P 8-8 
6000 Series Cylinder Drawing  
						

							 
 
 
Section 9. Electrical Information 
 
 
The motor supplied as standard is 208/230/460V 3-phase motor, with connection 
diagrams on the outside of the motor for low voltage, 230V or high voltage, 460V.  This 
motor connection is also rated for 208V.  As any standard motor is rated for +/-10% of 
voltage variation, this motor will operate properly, within ratings, at 208, 220, 230, 240, 
440, 460, and 480V, 3-phase supply. There are other motor configurations including 
single phase 115V & 230V. If you are unsure of the correct voltage or phase, contact 
the factory before applying line voltage.  
 
If the standard motor is intended for 208V line usage, some caution is advised.  If your 
motor is a 230V motor, and your 208V line voltage drops to 207 Volts (a drop of only 
½%), the motor will be operating at -10% in a marginal region.  Wiring runs and actual 
208 voltages become very important.  If your line voltage varies (due to loads elsewhere 
in the system, etc.) you may have an advantage by ordering as an option a specific 
208V +/-10% motor. 
 
To reverse the direction of rotation on a 3-phase motor, reverse any two of the three 
power leads to the motor.  On single-phase motors, see wiring diagram on motor. 
 
Field Changes in Voltage:  
Advance Lifts’ standard electrical supplied is 230V, 3-phase unless otherwise specified.  
Any field change in supply voltage would entail the following changes.  
 
230V to 460V 
 
A.  Change transformer primary connections to 460V. 
B.  Change overload protection to proper value as per currents in motor tables. 
Order new overload; adjust new overload to motor full load current setting.  Insure 
the overload is set to “manual” reset, not “automatic” to insure the equipment cannot 
re-start automatically. 
C.  Change motor connections for high 460V. 
D.  Change plug and receptacle for power, if required. 
 
460V to 230V  
A.  Change transformer primary connections to 230V. 
B.  Change overload protection to proper value as per currents in motor tables.  Order 
new overload; adjust new overload to motor full load current setting.  Insure the 
overload is set to “manual” reset, not “automatic” to insure the equipment cannot re-
start automatically. 
C.  Change motor connections for low 230V. 
D.  Change plug and receptacle for power, if required. 
 
IMPORTANT:  When changing voltages, insure motor rotation is correct. 
 
 
 
 
 
P 9-1