Stanley GT18 Hydraulic Power Unit

Servicing the Stanley Power Unit

This manual contains safety, operation, and routine maintenance instructions. Stanley Hydraulic Tools recommends that servicing of hydraulic tools, other than routine maintenance, must be performed by an authorized and certified dealer. Please read the following warning.

WARNING: SERIOUS INJURY OR DEATH COULD RESULT FROM THE IMPROPER REPAIR OR SERVICE OF THIS TOOL.

REPAIRS AND / OR SERVICE TO THIS TOOL MUST ONLY BE DONE BY AN AUTHORIZED AND CERTIFIED DEALER.

For the nearest authorized and certified dealer, call Stanley Hydraulic Tools at the number listed on the back of this manual and ask for a Customer Service Representative.

Safety Symbols

Safety symbols and signal words are used to emphasize all operator, maintenance and repair actions which, if not strictly followed, could result in a life-threatening situation, bodily injury or damage to equipment.

• ! This is the safety alert symbol. It is used to alert you to potential personal injury hazards. Obey all safety messages that follow this symbol to avoid possible injury or death.
• DANGER This safety alert and signal word indicate an imminently hazardous situation which, if not avoided, will result in death or serious injury.
• WARNING This safety alert and signal word indicate a potentially hazardous situation which, if not avoided, could result in death or serious injury.
• CAUTION This safety alert and signal word indicate a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.
• CAUTION This signal word indicates a potentially hazardous situation which, if not avoided, may result in property damage.
• NOTICE This signal word indicates a situation which, if not avoided, will result in damage to the equipment.
• IMPORTANT This signal word indicates a situation which, if not avoided, may result in damage to the equipment.

Always observe safety symbols. They are included for your safety and for the protection of the tool.

Local Safety Regulations

Enter any local safety regulations here. Keep these instructions in an area accessible to the operator and maintenance personnel.

Safety Precautions

Tool operators and maintenance personnel must always comply with the safety precautions given in this manual and on the stickers and tags attached to the equipment. These safety precautions are given for your safety. Review them carefully before operating the tool and before performing general maintenance or repairs.

Supervising personnel should develop additional precautions relating to the specific work area and local safety regulations. If so, place the added precautions in the space provided on page 4.

In addition to this manual, read and understand safety and operating instructions in the Engine Operation Manual furnished with the power unit.

The GT18 Hydraulic Power Unit will provide safe and dependable service if operated in accordance with the instructions given in this manual. Read and understand this manual and any stickers and tags attached to the Power Unit. Failure to do so could result in personal injury or equipment damage.

• Operator must start in a work area without bystanders. The operator must be familiar with all prohibited work areas such as excessive slopes and dangerous terrain conditions.
• Establish a training program for all operators to ensure safe operation.
• Do not operate the power unit unless thoroughly trained or under the supervision of an instructor.
• Always wear safety equipment such as goggles, ear, head protection, and safety shoes at all times when operating the power unit and a hydraulic tool.
• Do not inspect or clean the power unit while it is running. Accidental engagement of the unit can cause serious injury.
• Always use hoses and fittings rated at 2500 psi/172 bar with a 4 to 1 safety factor. Be sure all hose connections are tight.
• Be sure all hoses are connected for correct flow direction to and from the tool being used.
• Do not inspect hoses and fittings for leaks by using bare hands. "Pin-hole" leaks can penetrate the skin.
• NEVER OPERATE THE POWER UNIT IN A CLOSED SPACE. Inhalation of engine exhaust can be fatal.
• Do not operate a damaged, improperly adjusted power unit.
• Never wear loose clothing that can get entangled in the working parts of the power unit.
• Keep all parts of your body away from the working parts of the power unit.
• Keep clear of hot engine exhaust.
• Do not add fuel to the power unit while the power unit is running or is still hot.
• Do not operate the power unit if gasoline odor is present.
• Do not use flammable solvents around the power unit engine.
• Do not operate the power unit within 3.3 ft/1 m of buildings, obstructions or flammable objects.
• Do not reverse tool rotation direction by changing fluid flow direction.
• Allow power unit engine to cool before storing in an enclosed space.
• Always keep critical tool markings, such as labels and warning stickers legible.
• To avoid personal injury or equipment damage, all tool repair, maintenance and service must only be performed by authorized and properly trained personnel.

Tool Stickers & Tags

The GT18 Hydraulic Power Unit has various decals and tags for identification and safety. Key decals include the Power Unit Dash Decal (62302) and the Single Circuit Decal (62300). Specific models with the POWERLINK™ feature may have additional decals like 62318 and 62305.

These decals contain important information such as voltage (12v), danger warnings, choke operation (PULL TO START), and AC power ratings (AC 110V 1000W MAX CONTINUOUS).

Hydraulic Hose Requirements

Hose Types

Hydraulic hose types authorized for use with Stanley Hydraulic Tools are:

1. Certified non-conductive
2. Wire-braided (conductive)
3. Fabric-braided (not certified or labeled non-conductive)

Hose type 1 is the only type authorized for use near electrical conductors. Hoses 2 and 3 are conductive and must never be used near electrical conductors.

Hose Safety Tags

To ensure safety, DANGER tags are attached to all hose purchased from Stanley Hydraulic Tools. These tags must not be removed. If a tag becomes illegible due to wear or damage, it should be replaced immediately by obtaining a new tag from a Stanley Distributor.

Certified Non-Conductive Hose Tag: Contains warnings about potential death or serious injury from using non-conductive hose near electric lines, proper training requirements, cleaning and testing procedures for non-conductive hose, warnings against exceeding pressure ratings or abusing the hose, instructions on handling and routing to avoid damage, and a requirement to replace damaged hoses.

Conductive Hose Tag: Contains warnings against using this hose near electric lines, stating it is not certified as non-conductive and may result in death or serious injury. It also includes similar warnings regarding pressure, abuse, handling, routing, and replacement as the non-conductive hose tag.

Hose Pressure Rating

The rated working pressure of the hydraulic hose must be equal to or higher than the relief valve setting on the hydraulic system.

HTMA Requirements

The following table outlines the Hydraulic Tool Manufacturers Association (HTMA) requirements for different tool categories:

NOTE: Do not operate the tool at oil temperatures above 140° F (60° C). Operation at higher temperatures can cause operator discomfort at the tool.

*SSU = Saybolt Seconds Universal

NOTE: These are general hydraulic system requirements. See tool Specification page for tool specific requirements.

Operation

Preparation for Use

Do not operate the power unit until you have read the engine operating and maintenance instructions manual furnished with the unit.

1. Engine Crankcase Oil Level

Always check the oil level before starting the engine. Make sure the oil level is at the FULL MARK on the dipstick. Do not overfill. Use detergent oil classified "For Service SE, SF, SG" as specified in the engine operating and maintenance manual. See engine manual for oil viscosity grade.

2. Spark Plug

On power units equipped with Briggs & Stratton Engines, ONLY Champion RC12YC or equivalent can be used. For power units equipped with Honda Engines, ONLY Denso J16CR-U or equivalent can be used.

Incorrect type spark plugs can produce radio frequency interference that will corrupt and damage the controller. Failure to use the correct spark plug could result in a warranty that will not be considered.

3. Engine Fuel Level

Check the fuel level. If low, fill with un-leaded gasoline with a minimum of 85 octane.

4. Hydraulic Fluid

Check the dipstick in the hydraulic fluid reservoir for the proper fluid level. Use fluids meeting the following specifications:

Viscosity (Fluid Thickness)

Pour Point: -10°F/-23°C Minimum (for cold startup)

Viscosity Index (ASTM D-2220): 140 Minimum

Demulsibility (ASTM D-1401): 30 Minutes Maximum

Flash Point (ASTM D-92): 340°F/171°C Minimum

Fluid Specifications:

• Rust Inhibition (ASTM D-665 A & B) Pass
• Oxidation (ASTM D-943) 1000 Hours Minimum
• Pump Wear Test (ASTM D-2882) 60 mg Maximum

The following fluids work well over a wide temperature range, allow moisture to settle out and resist biological growth that may occur in cool operating hydraulic circuits. These fluids are recommended by Stanley. Other fluids that meet or exceed the specifications of these fluids may also be used:

• Chevron AW-MV-32
• Exxon "Univis" J-26
• Mobil D.T.Ε. 13
• Gulf "Harmony" AW-HVI-150-32
• Shell "Tellus" T-32
• Texaco "Rando" HD-AZ
• Union "Unax" AW-WR-32
• Terresolve EnviroLogic 132

5. Hydraulic Connections

The recommended hose length is 25 ft/8 m with a 1/2 inch/12.7 mm inside diameter. The hoses must have a working pressure rating of at least 2500 psi/175 bar. Each hose end must have male thread ends compatible with H.T.M.A. (HYDRAULIC TOOL MANUFACTURERS ASSOCIATION) quick disconnect fittings (NPT type threads).

Figure 1. Panel Control Valve: Depicts the control panel. The bottom male quick disconnect fitting is the PRESSURE FLUID OUT fitting. The top female quick disconnect fitting is the RETURN FLUID IN fitting.

Quick Disconnect Couplers: H.T.M.A. approved quick disconnect couplings are installed to hydraulic hoses so that the direction of oil flow is always from the male to the female quick disconnect.

6. Battery

The supplied 12 Volt DC battery is a non-spillable, maintenance-free battery and is fully charged. Make sure the battery cables are tight and charging circuit functions are operating properly.

NOTICE: Do not charge the battery with a standard automotive battery charger. This type of charger produces a charging amperage higher than 2 amps. Charging the battery at higher than 2 amps will damage the battery.

NOTICE: If the engine runs out of gas or dies during operation and the ignition switch is left in the ON or RUN position, this could drain the battery. Make sure the ignition switch is returned to the OFF position.

Figure 1. Hydraulic Connections: Illustrates the hydraulic connections, showing male and female quick disconnect couplers, hose ends, and adapter fittings. It specifies the required hose specifications (1/2 inch I.D., 25 ft long, 2500 PSI/172 BAR RATING AND 4 TO 1 SAFETY FACTOR).

Controls

This unit is equipped with an advanced proportional engine control system that controls engine speed by adjusting the fuel control lever with a proportional actuator. The Power Unit provides one circuit with oil flow options of 5 gpm/19 lpm or 8 gpm/30 lpm, both up to 2000 psi/140 bar, with a factory-programmed electronic governed engine throttle.

Figure 3. Panel Control Valve: Shows the control panel with various switches and indicators: THROTTLE CONTROL SWITCH, AC CONTROL SWITCH, FLOW SELECTOR SWITCH, IGNITION SWITCH. It also shows the flow rate selector (5 GPM, 8 GPM) and an ON/OFF switch.

One hydraulic tool can be connected. The circuit is activated by turning the flow control switch to either the 5 gpm/19 lpm or 8 gpm/30 lpm setting.

Throttle Control

The throttle control permits the operator to select one of two operating modes after the engine has warmed up. When starting the engine, ensure the flow selector switch is in the OFF position. The throttle control switch can be set to either AUTO-IDLE-ON or AUTO-IDLE-OFF.

• AUTO-ON: When set to "AUTO-ON", oil flow is regulated automatically when the tool trigger is activated. When the tool is not used, the engine returns to idle after a 10-second delay. This setting produces 5 gpm/19 lpm or 8 gpm/30 lpm based on the flow selector switch position.
• AUTO-OFF: When set to "AUTO-OFF", the engine speed is held to maintain 5 gpm/19 lpm or 8 gpm/30 lpm. When a tool is not used, the engine will not return to idle until the flow selector switch is turned to OFF or the throttle control switch is turned to AUTO-ON.

Controller Reset: It may be necessary to reset the controller if a fault occurs (e.g., excessive engine speed). To reset, turn the power unit off and restart it.

Using the 110 Volt AC Outlet

The 110 volt AC outlet is available on specific models with the Briggs & Stratton engine. The POWERLINK™ system output remains 110 volts across the engine speed range, with wattage increasing with engine speed. To use this feature, turn the AC control switch to the ON position. The outlet can be used in 8 gpm mode but is disabled in 5 gpm mode. Refer to the POWERLINK™ On-Board Generator System Manual for details.

Using the 12 Volt DC Outlet

A 12 VDC outlet is available on specific models and is ON at all times. Accessories left plugged into this outlet could drain the battery.

Startup

Before starting the engine, ensure the flow selector switch is in the OFF position. The power unit will not start if the flow control switch is not in the "OFF" position.

Pull the choke knob out and move the Throttle Control Switch to the auto-idle-off or auto-idle-on position. Ensure the flow selector switch is in the OFF position.

For units with the POWERLINK™ feature, it is good practice to start the power unit with the AC Control Switch in the OFF position. The unit will start regardless of the AC Control Switch position.

Note: If the power unit is started with the ON position, the 110 volt AC outlet will not function unless the switch is turned off and back on again.

Turn the Ignition Switch to the START position. After the engine starts, release the switch. Gradually push in the choke knob as the engine begins to idle smoothly. Allow the engine to warm up. Connect hoses and the tool as described on pages 9 and 10.

For 5 GPM Operation

Select the desired throttle mode (auto-idle-on or auto-idle-off) with the Throttle Control switch. Move the flow selector switch to the 5 gpm position. When finished, move the flow selector switch to the OFF position.

For 8 GPM Operation

Select the desired throttle mode (auto-idle-on or auto-idle-off) with the Throttle Control Switch. Move the flow selector switch to the 8 gpm position. When finished, move the flow selector switch to the OFF position.

Cold Weather Startup

1. Follow the general "STARTUP" procedures.
2. Hydraulic fluids are thicker in cold weather. Run the engine at low idle long enough to bring the fluid temperature up to a minimum of 50°F/10°C.
3. If tools and hoses are cold, allow hydraulic fluid to circulate through the tool hoses until warm before using the tool.

Shutdown

1. Ensure the flow selector switch is in the OFF (center) position.
2. The power unit should return to idle (this may take a few seconds due to program delay).
3. Allow the engine to idle for approximately one minute and move the Ignition Switch to the OFF position.

Routine Maintenance

Engine Maintenance

Follow the maintenance schedule and general maintenance instructions in the engine maintenance and operation manual furnished with the power unit.

Spark Plugs

On power units equipped with Briggs & Stratton Engines, ONLY Champion RC12YC or equivalent can be used. For power units equipped with Honda Engines, ONLY Denso J16CR-U or equivalent can be used. Incorrect type spark plugs can produce radio frequency interference that will corrupt and damage the controller. Failure to use the correct spark plug could result in a warranty that will not be considered.

Hydraulic System Maintenance

• Check hydraulic fluid level daily. Add fluid per specifications in this manual (See "HYDRAULIC FLUID" under "OPERATING INSTRUCTIONS").
• Remove condensed moisture from the hydraulic fluid by pumping the fluid into a 5 gal/20 l container through the pressure hose. Perform this with the engine at idle. Turn the engine off immediately when the hydraulic reservoir is empty.
• Allow the fluid to sit long enough for water to settle to the bottom of the container. Slowly pour the fluid back into the hydraulic tank, avoiding the water.
• Each day, check hydraulic lines and fittings for leaks, kinks, etc. Do not use your hand for this check.
• Change the hydraulic filter element every 200 hours of operation. Change more often if cold, moist, or dusty conditions exist.
• Check oil cooler for debris. Remove debris with air pressure.

Storage

• Clean the unit thoroughly before storage. Do not use water pressure.
• Always store the unit in a clean and dry facility.
• If the unit will be stored for a prolonged period (over 30 days), add a fuel additive to the fuel tank to prevent gumming. Run the engine for a short period to circulate the additive.

Programmable Controller

The Stanley programmable controller is an electronic engine governor that controls and limits engine speed by adjusting the fuel control lever with a proportional actuator. The controller is software programmable and has no manual adjustments. A flashing LED indicates a fault condition.

Checking Performance Control™ (Electronic Governor-Static Check)

To determine if a governor problem is caused by the actuator or the control module, perform the following static check:

1. Disconnect red and green wires from the control module to the actuator.
2. Attach jumper wires from a known good 12-volt battery to the RED and GREEN wires of the actuator.
• Attach 12 volt + (positive) to the RED wire.
• Attach 12 volt – (negative) to the GREEN wire.
3. The actuator should move the throttle lever to the wide-open position.
• If the actuator does not move, it is defective and should be replaced.
• If the actuator moves the throttle to wide-open position, the module is defective and should be replaced.

Calibration

ACT (PC-based software) is used for calibration and monitoring. Stanley Hydraulic Tools recommends that an authorized and certified dealer perform calibration. Once programmed, ACT can be disconnected.

Troubleshooting Guidelines

Follow this checklist to troubleshoot the Stanley controller:

1. Check battery voltage for stability and correct value. The LED will turn on for one second when the controller is first powered up.
2. Check the actuator linkage for binding and backlash.

Fault Codes

The Stanley controller identifies fault conditions via a flashing LED. The current fault code list is shown below. Note:

1. When power is applied, the LED flashes once for one second to indicate it is working.
2. Multiple faults are indicated by sequential flashes. Count the flashes or use the Calibration Tool's "Display Faults" option.
3. If no faults exist, the LED flashes once at reset and then indicates engine speed. A continuous ON LED signifies valid engine speed sensing.
4. The controller may attempt to shut down for some faults and prevent starting after reset with faults 1, 5, and 8.

Testing & Troubleshooting

General

Tests and adjustments should be performed periodically to ensure the power unit is operating at maximum efficiency. The Stanley Circuit Tester (part number 04182) is recommended for isolating problems in the engine and hydraulic system before disassembly.

Testing the Hydraulic Circuit

The following tests ensure the hydraulic pump supplies correct flow and pressure, and the system relief valve operates properly. Ensure the engine is warm and operating smoothly during these tests. Refer to the troubleshooting table for possible causes if test results are not as specified.

Testing the 5 GPM HTMA Type 1 Circuit

1. Set the flow selector switch to the OFF (center) position.
2. Set the throttle control switch to AUTO-OFF position.
3. Connect the Stanley Circuit Tester across two hose ends (where the tool would normally be connected).
4. Fully open the tester restrictor valve (counterclockwise).
5. Start the engine and allow it to run until warm.
6. Switch the flow selector switch to 5 or 8 gpm depending on which flow you are testing.
7. With the engine at the programmed speed, the test flow gauge should read 4-6 gpm/15-23 lpm or 7-9 gpm/26.5-34 lpm.
8. Slowly turn the restrictor valve clockwise while watching the pressure gauge. The flow rate should stay at 4-6 gpm/15-23 lpm or 7-9 gpm/26.5-34 lpm as the pressure gauge reaches 2100-2200 psi/148-155 bar.
9. At 2100-2200 psi/148-155 bar, the relief valve should begin to open (cracking pressure). At this point, the flow rate should start to drop as fluid bypasses to the reservoir. If the cracking pressure is not within the specified range, the relief valve must be re-set:
• The relief valve is located on the right side of the unit, behind the dash panel, protruding from the manifold assembly. Use an open or box end wrench to loosen the nut on the relief valve.
• Use an Allen wrench to adjust the relief valve: turn clockwise to raise pressure, counterclockwise to reduce pressure.
• Tighten the nut and retest.

Troubleshooting Table:

Specifications

• Engine: 18 hp Briggs / 20 hp Honda
• Capacity: One 5 gpm/19 lpm Circuit or One 8 gpm/30 lpm Circuit
• Length: 36 in. / 91.4 cm
• Width: 23 in. / 58.4 cm
• Height: 29.5 in. / 74.9cm
• Weight (Wet): Single Circuit Briggs: 330 lbs / 149.6 kg
• Weight (Wet): Single Circuit Honda: 348 lbs / 157.8 kg
• Fuel Tank Capacity: 7 gal. / 26.5 ltr
• Estimated Gas Consumption Per Hour: 1.3 gal / 4 ltr
• Hydraulic Reservoir Capacity: 3 gal. / 11 ltr
• Relief Valve "crack" setting: 2100 psi / 145 bar
• Full relief setting: 2500 psi / 172 bar
• HTMA Category: "C" (20 lpm @ 138 bar) or "D" (30 lpm @ 138 bar)
• Sound Power Level: 100 dBA
• Vibration Level: N/A

Parts Lists & Illustrations

Figure 1. Briggs Engine Assembly

This is an exploded view diagram illustrating the assembly of the Briggs & Stratton engine, with various components numbered for reference in the parts list.

Figure 1. Briggs Engine Parts List

Figure 1A. Honda Engine Assembly

This is an exploded view diagram illustrating the assembly of the Honda engine, with various components numbered for reference in the parts list.

Figure 1A. Honda Engine Parts List

Figure 2. Frame Parts

This diagram illustrates the assembly of the power unit's frame, showing components such as the handle, couplers, switches, decals, and the 12-volt receptacle. It also details the wiring harness for the 12-volt receptacle.

Figure 3. Hoses, Fittings & Clamps

This diagram shows the routing and connection of hydraulic hoses, fittings, and clamps on the power unit. It includes numbered parts like the manifold assembly, hose barbs, elbows, adapters, and connectors.

Figure 4. Additional Wiring Diagram for Honda Power Units Only

This diagram illustrates the specific wiring connections for Honda engines, showing connections to the actuator, fuel shut-off, engine kill, rectifier, and magneto wire. It includes photos showing the location of the Magneto Wire Connection and a receptacle connected to the Pick-up Coil.

Figure 4A. POWERLINK™ Wiring Diagram

This diagram details the wiring for the POWERLINK™ feature, which is available on specific models with Briggs & Stratton engines. It shows connections from the dash panel GFCI outlet to the inverter and from the engine to the inverter, including the AC control switch and wiring views.

Figure 4B. Main Power Unit Wiring Harness

This diagram shows the main power unit wiring harness, illustrating connections for the throttle control switch, flow selector switch, start switch, hour meter, pressure switch, relay, battery, starter solenoid, controller, oil pressure switch, fuel shutoff, and engine kill. It also includes a detailed view of the engine oil press switch wiring.

Warranty

Stanley Hydraulic Tools warrants new hydraulic tools for one year from the date of sale to the first retail purchaser, or two years from the shipping date from Stanley, whichever expires first, to be free of defects in material and/or workmanship at the time of delivery. Stanley will, at its option, repair or replace any defective tool or part.

Exceptions from Warranty:

• New Parts: Warranted for 6 months after date of first usage or 2 years from shipping date, whichever is first. Labor is not covered.
• Seals & Diaphragms: Warranted for 6 months after date of first usage or 2 years from shipping date, whichever is first.
• Cutting Accessories: Warranted only at the time of delivery.
• Items Produced by Other Manufacturers: Warranted by their respective manufacturers.
• Alterations & Modifications: Warranty is void if the tool or part is altered or modified.
• Normal Wear: Failures due to normal wear and tear are not covered.
• Incidental/Consequential Damages: Stanley is not liable for such damages.
• Freight Damage: Damage caused by improper storage or freight handling is not covered.
• Loss Time: Loss of operating time is not covered.
• Improper Operation: Failures due to not following guidelines in the manual are not covered.
• Maintenance: Failures due to not maintaining the tool in good operating condition are not covered.
• Hydraulic Pressure & Flow, Heat, Type of Fluid: Failures attributable to excess pressure, back-pressure, flow, heat, or incorrect fluid are not covered.
• Repairs or Alterations: Failures due to unauthorized repairs are not covered.
• Mis-Application: Failures due to using the product for unintended purposes without written consent are not covered.

Warranty Registration: Stanley assumes no liability for warranty claims without tool registration on record. Proof of sale or first date of usage is required.

No Additional Warranties: This limited warranty is in lieu of all other warranties, expressed or implied, including merchantability or fitness for a particular purpose.

Contact Information

Stanley Hydraulic Tools

3810 SE Naef Road

Milwaukie, Oregon

Phone: 503-659-5660 / Fax: 503-652-1780

Website: www.stanleyhydraulic.com