XP20HP U S E R M A N U A L REV: XP20HP_rev12072022 This manual provides information regarding the operation and maintenance of these products. We have made every effort to ensure the accuracy of the information in this manual. We reserve the right to change this product at any time without prior notice. 5800 Ontario Mills Pkwy Ontario, CA 91764 USA www.duromaxpower.
CONTENTS 1. Introduction Introduction ..................................................................................................................... 6 General Safety Procedures............................................................................................. 8 Unit and Purchase Information................................................................................... 12 Engine Components...................................................................................................
CONTENTS 5. Specifications Specifications.................................................................................................................. 43 Adjustment and Torque Value Specifications............................................................ 44 Engine Diagrams............................................................................................................ 45 Wiring Diagram.........................................................................................................
THE DUROMAX WAY The DuroMax Way is more than just a brand, it is our understanding and appreciation of just how important power can be to someone without it… DUROMAX FOR HOME Electricity in our home not only provides comfort but safety as well. From keeping the heat or A/C on to keeping our food cold, power is essential to our daily lives. Inevitability when disaster strikes and we are left without power for a prolonged period of time, our way of life is put at risk.
INTRODUCTION DuroMax Power Equipment is headquartered in Ontario, California and is the industry’s leader in Dual Fuel portable generator technology. In addition to a full assortment of portable generators ranging from digital inverters to large 15,000-watt portable standby units, their product line includes pressure washers, engines, pumps, and accessories. The foundation of our company is built on quality, reliability, durability, and customer service.
GENERAL SAFETY PROCEDURES SAFETY ALERT SYMBOL The safety alert symbol is used with one of the safety words (DANGER, WARNING, or CAUTION) to alert you of hazards. Please pay attention to these hazard notices both in this manual and on the engine. Please familiarize yourself with the following safety symbols and words: ● DANGER: Indicates a hazard that will result in serious injury or death if instructions are not followed.
WARNING: This engine may emit highly flammable and explosive gasoline vapors, which can cause severe burns or even death. A nearby open flame can lead to an explosion even if not directly in contact with gasoline. ● Do not operate near an open flame. ● Do not smoke near the engine. ● Always operate on a firm, level surface. ● Always turn the engine off before refueling. ● Allow engine to cool for at least 2 minutes before removing the fuel cap. Loosen cap slowly to relieve pressure in the tank.
GENERAL SAFETY PROCEDURES (CONTINUED) In addition to the above safety notices, please familiarize yourself with the safety and hazard markings on the engine. 1.
UNIT AND PURCHASE INFORMATION Serial Number Serial number The serial number is located on the engine block, to the left of the oil fill. Serial number format The serial number will be shown in two parts. The engine model, followed by the serial number. Engine Model: _____________________________________________ Serial Number: _____________________________________________ STAPLE RECEIPT HERE A purchase receipt may be necessary for warranty parts or service in the future.
ENGINE COMPONENTS 1. Air Filter 3. Fuel Tank 5. Recoil Handle 6. Muffler 7. Engine Shaft 2. Carburetor 8. Oil Fill 4. Recoil Starter 9. Oil Drain Plug 1. Air Filter - A removable, cleanable, oiled, element that cleans the air going into the engine. 2. Carburetor - A component used to control the air fuel mixture of the engine. 3. Fuel Tank - All metal 1.35 gallon gasoline fuel tank. 4. Recoil Starter - An easy pull recoil start to start the engine without the electric start. 5.
PACKAGE CONTENTS Your engine comes with the items listed below. Please check to see that all of the following items are included with your engine. Spark Plug Wrench Oil Funnel Used in spark plug maintenance, inspection, and installation. Used to add oil to the engine without messy spills. ● Note: Actual tools may differ in appearance or design from image shown.
ENGINE SETUP Proper setup of your engine will get you going as soon as possible while making sure you and your equipment are safe and cared for.
ENGINE SETUP Step 1- Adding Oil The engine requires engine oil to operate properly. The engine, when new from the package contains no oil in the crankcase*. You must add the proper amount of oil before operating the engine for the first time. This amount is equal to the oil capacity of the engine crankcase: Model Number XP20HP Engine Oil Capacity 40.5 fl. oz (1.
Step 2 - Adding Gasoline Add gasoline a. Make sure the engine is on a level surface. b. Unscrew gas cap and set aside (NOTE: the gas cap may be tight and hard to unscrew). c. Slowly add unleaded gasoline to the fuel tank. Be careful not to overfill. d. Replace fuel cap and wipe up any spilled gasoline with a dry cloth. Model Number XP20HP Gas Tank Capacity 1.35 US gal. (5.1 L) DANGER 1.5” DO NOT OVERFILL THE GAS TANK OVERFILLING CAN RESULT IN A FIRE, EXPLOSION, OR DEATH.
ENGINE SETUP (CONTINUED) High Altitude Operation At high altitudes, the standard carburetor air/fuel mixture will be too rich. The performance will decrease, and fuel consumption will increase. A very rich mixture will also foul the spark plug and cause hard starting. Operation at an altitude that differs from that at which this engine was certified, for extended periods of time, may increase emissions. High altitude performance can be improved by specific modifications to the carburetor.
STARTING THE ENGINE If this is not your first time using the engine there are still steps you should take to prepare it for operation each time you use it. IMPORTANT: At this point you should be familiar with the procedures described in the first portion of this section entitled “ENGINE SETUP” If you have not yet read this section, go back and read it now.
BEFORE YOU START YOUR ENGINE Step 1 - Check the Oil Check the oil The engine is equipped with an automatic shutoff to protect it from damage due to low oil. Nonetheless, you should check the oil level of the engine before each use to ensure that the engine crankcase has a sufficient amount. To check the oil level: 20 a. Make sure the engine is on a level surface. b. Unscrew the oil filler/dipstick cap. c. With a dry cloth, wipe the oil off of the stick on the inside of the cap. d.
Step 2 - Check the Fuel Level Check fuel level Before starting your engine, check to see that there is sufficient gasoline in the fuel tank. The gasoline level should always be under the red fuel level indicator located on the bottom of the fuel filter cup. DANGER 1.5” DO NOT OVERFILL THE GAS TANK OVERFILLING CAN RESULT IN A FIRE, EXPLOSION, OR DEATH. WARNING: Gasoline and gasoline fumes are highly flammable. ● Do not fill the tank near an open flame.
STARTING THE ENGINE (CONTINUED) Starting the Engine 1. Move fuel valve to ON The gas valve is located above the carburetor bowl. Move the gasoline fuel valve lever all the way to the right-hand position to allow gasoline to flow to the engine carburetor. 2. Move choke lever to ON The choke lever is located above the gas valve. Move the choke lever to the left-hand side to the “ON” position to start. Please note that if the engine is hot, turning the choke on is unnecessary. 3.
5. Pull the recoil start handle Pull the recoil handle slowly until resistance is felt, then quickly pull the recoil handle until fully extended. Continue this step until the engine starts as needed. CAUTION: Release the recoil handle only after the cord has retracted. Releasing the recoil handle while extended may cause harm to yourself or your equipment. 6.
MAINTENANCE AND CARE Proper maintenance and storage of your engine is essential to ensure trouble free use of your Engine when you need it. By following the maintenance and care requirements, you can keep your engine running smooth and efficient for years to come.
MAINTENANCE AND CARE Proper routine maintenance of your engine is essential for safe, economical, and trouble-free operation. It will also help reduce air pollution. WARNING: Improper maintenance, or failure to correct a problem before operation, can cause a malfunction in which you can be seriously injured or killed. Always follow the inspection, maintenance recommendations, and schedules in this instruction manual. ● Make sure the engine is off before you begin any maintenance or repairs.
Break-In Period As the best practice for any new combustion motor it’s recommended to perform the break in procedure as follows: ● Run the engine for the first 6-8 hours on conventional oil, then change the oil. After the break-in period synthetic oil may be used. ● During the break in period of the first 6-8 hours keep the engine speed under 50% for optimal results. ● Check and clean the air filter if necessary after the break-in period.
MAINTENANCE AND CARE (CONTINUED) Checking the Oil Check the oil The engine is equipped with an automatic shutoff to protect it from damage due to low oil. Nonetheless, you should check the oil level of the engine before each use to ensure that the engine crankcase has a sufficient amount. To check the oil level: 28 a. Make sure the engine is on a level surface. b. Unscrew the oil filler/dipstick cap. c. With a dry cloth, wipe the oil off of the stick on the inside of the cap. d.
Changing the Oil CAUTION: Worn out or dirty oil does not cool the engine properly and can lead to catastrophic engine damage. In addition to regular oil changes, it is necessary to drain the oil from the crankcase if it has become contaminated with water or dirt. 1. Remove drain plug Using a 12 mm hex wrench, unscrew the oil drain plug, which is located on the crankcase underneath the oil filler/dipstick cap. Allow all the oil to drain from the engine. 2.
MAINTENANCE AND CARE (CONTINUED) Changing the Air Filter Routine maintenance of the air cleaner helps maintain proper airflow to the carburetor. Check that the air cleaner is free of excessive dirt after every use. CAUTION: Improper maintenance may cause less air to enter the engine or dirty air to enter the engine causing overheating and engine wear. 1. Remove filter cover wing nut Remove the top screw located on the top of the air filter cover. 2.
4. Replace new filter element Slide new filter element over center bolt, and replace wing nut. Tighten wing nut hand tight to keep filter in place. 5. Replace filter cover Replace plastic air filter cover over the air filter base. 6. Secure filter cover Fasten the air filter cover with the air filter cover wing nut and tighten about hand tight.
MAINTENANCE AND CARE (CONTINUED) Spark Plug Maintenance SPARK PLUG CONSULT MANUAL BEFORE REMOVING The spark plug is important for proper engine operation. A good spark plug should be intact, free of deposits, and properly gapped. CAUTION: Improper maintenance may cause reduced fuel economy, misfires, trouble starting, or damage to the spark plug threads. 1. Remove spark plug cap Pull on the spark plug cap to remove it. 2.
4. Measure plug gap Measure the plug gap with a gauge. The gap should be 0.7-0.8 mm (0.028-0.031 in). 5. Clean and re-gap If you are re-using the spark plug, use a wire brush to clean any dirt from around the spark plug base and then re-gap the spark plug. 6. Install spark plug Screw the spark plug back into its place on the engine using the spark plug wrench. 7. Replace spark plug cap Replace the spark plug cap.
MAINTENANCE AND CARE (CONTINUED) Emptying the Gas Tank If you have been using gasoline in your engine, before storing your engine for extended periods of time you should drain your engine fuel tank of gasoline. CAUTION: Do not store fuel from one season to another. Gasoline sold at the pump today contains additives such as ethanol that even when stored properly may damage the fuel system components. 1. Shut fuel valve OFF Turn the fuel valve to the “OFF” position. 2.
4. Turn fuel valve ON and drain Turn the fuel valve to “ON” and allow gasoline to drain into the container until the gas tank is empty. 5. Shut fuel valve OFF Once the gasoline is fully drained, move the fuel valve back to the “OFF” position. 6. Replace carburetor drain bolt Reinstall the carburetor drain bolt. 7. Store emptied gasoline Store the emptied gasoline in a suitable place and add fuel stabilizer to keep fuel fresh and usable.
MAINTENANCE AND CARE (CONTINUED) Storing the Engine for Same Day Use 1. Run the engine Allow the engine to run for 3-5 minutes. 2. Turn engine switch to OFF Flip the switch down to the “OFF” position to shut the engine off. 3. Store engine After the engine shuts off and cools, then you can store the engine. CAUTION: Do not obstruct any ventilation openings and keep the engine in a cool dry area.
Storing the Engine for Use Within 30 Days 1. Run the engine Allow the engine to run for 3-5 minutes. 2. Shut fuel valve OFF and run dry Shut the fuel valve “OFF” and allow engine to run until it stalls out. 3. Turn the engine switch OFF Flip the switch down to the “OFF” position to shut the engine off. 4. Add fuel stabilizer and store Add fuel stabilizer to gas remaining in tank, and store the engine.
MAINTENANCE AND CARE (CONTINUED) Storing the Engine for Longer Than 30 Days 1. Run the engine Allow the engine to run for 3-5 minutes. 2. Shut fuel valve OFF and run dry Shut the fuel valve “OFF” and allow engine to run until it stalls out. 3. Turn the engine switch OFF Flip the switch down to the “OFF” position to shut the engine off. 4. Empty the gas tank Fully drain your gas tank as shown in “Emptying the Gas Tank” on page 34-35.
5. Remove spark plug Remove spark plug as shown in “Spark Plug Maintenance” on page 32. 6. Add oil to cylinder Add 2 tablespoons of 10W-30 motor oil directly into the spark plug hole, and pull the recoil to lubricate cylinder. After lubricating cylinder reinstall the spark plug as shown in “Spark Plug Maintenance” on page 33. 7. Store engine The engine is ready to be stored in a cool dry area. CAUTION: Do not obstruct any ventilation openings and keep the engine in a cool dry area.
SPECIFICATIONS A quick reference to useful information on your new DuroMax engine, please see this section for more details on this engine’s specifications.
SPECIFICATIONS Displacement 500cc Fuel Type ≥87 octane, ≤10% ethanol, unleaded gasoline Dry Weight 77 lbs Maximum Torque 22.87 ft. lb @ 2500 rpm Compression Ratio 8.5:1 Bore X Stroke 94 mm x 72 mm Engine Oil Capacity 40.5 oz. (1.2 L) Fuel Tank Capacity 1.35 gal. (5.1 L) Lowest Idling Speed 2100 rpm ± 200 rpm Dimensions LENGTH 19 in. WIDTH 17 in. HEIGHT 19 in.
SPECIFICATIONS (CONTINUED) Adjustment and Torque Value Specifications Adjustment Specification Spark Plug Clearance .027-.031 in. (0.7-0.8 mm) Spark Plug Type F6TC (Torch), BP6ES (NGK), RN9YC (Champion), W7DC (Bosch), W20EP-U (Denso) Valve Clearance (Cold) Intake: .00295 in ± .00098 in. (0.075 mm ± 0.025 mm) Exhaust: .00295 in ± .00098 in. (0.075 mm ± 0.025 mm) Carburetor Idling 2100 ± 200 rpm Torque Values Charging Coil Bolt 7.5 ± 1.5 ft. lb (10 ± 2 N·m) Crankcase Bolt 21 ± 1.5 ft.
103 44.7 41.3 0 41.3 44.7 Engine Diagrams 4×3/8-16UNC-2B 6×5/16-24UNF-2B 71.5 71.5 E 44.8 (30°) (30°) °) (45 44.8 35 0 Ø146-0.0063 (45 3.2 °) E B 0 0 (Ø165.2) (Ø126.5) C C 44.6 44.6 2×C2.5 Ø18 58.4 58.4 .5-6 H 25° 0×2 B 20 103 58.4 44.7 0 R8.7 44.7 5 58.4 21. 26 2×2 3.
3/8-24UNF2B TAP SPECIFICATIONS (CONTINUED) +0.05 6.3 0 Ø11.5 R0.16~R.25 28 mm 32 mm 60° 0 R12.7 R10 Ø21.8-0.02 89.8 mm 1.5 mm 6 mm 0 Ø25.4-0.025 56 mm 119.6 105 83 0 63 90.5 103 72.2 mm 125° 0 1 10 0 4×R13.5 4×R7 18.5 29 29 38 46 46 62 110° 70° 98.2 2×R6 113 2×Ø7 132 46 105 93.5 85 0 70.5 74.5 90.5 144.5 149.5 2×Ø23 113 2×Ø12 15° 132 136.
Wiring Diagram 1. Control Box 8. Oil Level Switch 2. Rectifier 9. Charging Coil 3. Fuse 10. Ignition Coil 4. Circuit Breaker 11. Spark Plug 5. Engine Switch 12. Starter Motor 6. Oil Alert Unit 13. Starter Solenoid 7. Type With Oil Alert Unit 14.
TROUBLESHOOTING This section of the manual is to help you troubleshoot problems with your engine.
TROUBLESHOOTING Mode Engine will not start Engine starts, but shuts off after running for short time.
WARRANTY This section of the manual is to help you understand your warranty.
WARRANTY 3-year Warranty All DuroMax Power Equipment warrant the original purchasers to a 3-year Parts Warranty (Residential Use ONLY: Unusually heavy or commercial use is covered for a period of 1-year) in the event of failure due to defects in electrical or mechanical components. Freight on any items submitted for replacement or repair under the Warranty are the responsibility of the equipment owner. This warranty is non-transferable and only valid to the original purchaser.
OWNER’S WARRANTY RESPONSIBILITIES: As the small off-road engine owner, you are responsible for performance of the required maintenance listed in your owner’s manual. DuroMax Power Equipment recommends that you retain all receipts covering maintenance on your small off-road engine, but DuroMax Power Equipment cannot deny warranty coverage solely for the lack of receipts or your failure to ensure the performance of all scheduled maintenance.
WARRANTY (CONTINUED) under warranty must be warranted for a time not less than the remainder of the period prior to the first scheduled replacement point for the part. 4. Repair or replacement of any warranted part under the warranty must be performed at no charge to the owner at a warranty station. 5. Notwithstanding the provisions of Subsection (4) above, warranty services or repairs must be provided at all manufacturer distribution centers that are franchised to service the subject engines. 6.
5. Catalyst or Thermal Reactor System i. Catalytic converter. ii. Thermal reactor. iii. Exhaust manifold. 6. Particulate Controls 7. Traps, filters, precipitators, and any other device used to capture particulate emissions. 8. Electronic controls. 9. Vacuum, temperature, and time sensitive valves and switches. 10. Hoses, belts, connectors, and assemblies. Evaporative Emission Warranty Part List 1.Fuel Tank 2.Fuel Cap 3.Fuel Line(for liquid fuel and fuel vapors) 4.Fuel Line Fittings 5.Clamps* 6.
CUSTOMER SERVICE DuroMax Power Equipment is committed to ensuring that our products perform when they need to. Our generators are your lifeline in the event of an emergency. Should you have any problems, please contact our customer service department: DUROMAX POWER EQUIPMENT 5800 Ontario Mills Parkway Ontario, CA 91764 Customer Service: 844-DUROMAX Customer Service Hours: 8-5 pm PST Website: www.duromaxpower.com Email: customerservice@duromaxpower.
5800 Ontario Mills Parkway Ontario, CA 91764 United States 844-DUROMAX REV: XP20HP_rev12072022
