DUROMAX XP18HP User manual

DuroMax XP18HP / XP18HPE
General Purpose Gasoline Engine
Owner's Manual

The manual gives information with respect to operation and maintenance of the general gasoline
engine. Be sure to read it carefully first before operating. All the materials and diagrams of this
manual are in accordance with the newest products at the publishing time. Due to revisions and
other changes, the information described in this manual may be slightly different than the engine
received. The copyright of this manual belongs to DuroMax Power Equipment, unauthorized
reproduction is prohibited. Manual is subject to change without notice.
Please familiarize yourself with the following safety symbols and words:
The safety alert symbol is used with one of the safety words (DANGER, CAUTION, or
WARNING) to alert you to hazards. Please pay attention to these hazard notices both in this
manual and on the generator.
DANGER: Indicates a hazard that will result in serious injury or death if instructions are not
followed.
WARNING: Indicates a strong possibility of causing serious injury or death if instructions are
not followed.
CAUTION: Indicates a possibility of personal injury or equipment damage if instructions are not
followed.

DANGER: This engine produces poisonous carbon monoxide gas when running. This gas is both odorless
and colorless. Even if you do not see or smell gas, carbon monoxide may still be present. Breathing this poison can
lead to headaches, dizziness, drowsiness, and eventually death.
Use outdoors ONLY in non-confined areas.
Keep several feet of clearance on all sides to allow proper ventilation of the engine.
WARNING: The exhaust from this product contains chemicals known to the State of California to cause
cancer, birth defects, or other reproductive harm.
WARNING: This generator may emit highly flammable and explosive gasoline vapors, which can cause
severe burns or even death. A nearby open flame can lead to explosion even if not directly in contact with gas.
Do not operate near open flame.
Do not smoke near generator.
Always operate on a firm, level surface.
Always turn generator off before refueling. Allow generator to cool for at least 2 minutes before removing
fuel cap. Loosen cap slowly to relieve pressure in tank.
Do not overfill gas tank. Gas may expand during operation. Do not fill to the top of the tank.
Always check for spilled gas before operating.
Empty the gasoline tank before storing or transporting the generator.
Before transporting, turn fuel valve to off and disconnect the spark plug.

CONTENTS
Safety Precautions …………………………………………………………… 1
Parts Description ……………………………….……………………………. 2
Control Connection of Remote Distance (optional) …………..…….………. 3
Pre-Operate Inspection …….………………………………………………… 4
Engine oil ………………..……………...………….…………………. 4
Air cleaner …...……………..…………………………………………. 5
Fuel and fuel tank ……………………………………...….…………... 6
Starting of the Engine ………………………………….…….………..……... 8
Operation ……………………………………………………………...……... 10
Stop ………………………………………………...………….……………... 12
Exhaust Control System …...…………………………………….…………... 13
Maintenance……………….………………………………….……………… 13
Replacement of parts…………………………………………….……. 13
Modifying…………………..………………………………………..… 14

Maintenance …………………………………………………………..…….. 15
Maintenance Schedule ………………………………...……………... 15
Maintenance Procedures …………………………….……….………. 17
Transport, Storage and Removal from Storage …………...………………..... 23
Transport ….………………………………………..………..……….. 23
Storage ………………………………………..………………………. 23
Removal from storage……………………….……………….……….. 24
Troubleshooting……………………………………………………..……….. 25
Will not start …….……………………….……………………………. 25
Low Power ………………..…………………………………………... 27
Running Rough ……………...…………………………………….….. 28
Engine Stalls ……….…………………………………….…….……... 29
Running Hot ……………..……………………………….…….……... 31
Excess or Abnormal Noise…………………………………….………. 32
Specifications…………………………………………………………..…….. 33
Main specifications……………..………………………….………..… 33
Timing of distribution………..………………………………………... 34
Torque of important bolts……….……………………….……………. 34
Electric Diagram………..………………………………..………….… 35

SAFETY PRECAUTIONS
WARNING
Before operating the engine, be sure to read and become familiar with the manual, otherwise
injury to personnel or damage to equipment may occur.
Please pay special attention to the following:
1. Run the engine in a well-ventilated place, keep it at least one meter away from building walls or
other equipment, and keep away from inflammables such as gasoline, matches and so on to avoid
the possibility of fire.
2. Keep the engine out of reach of children and pets to avoid accidents.
3. Be sure the operator of the engine has been specially trained.
4. Refuel in a well-ventilated area with the engine stopped, and in places refueling or storing
gasoline, no smoking, flames, or sparks.
5. When refueling, leave at least 1 inch of free space at the top of the tank to avoid spills and vapor
lock. If there is spilled fuel around, be sure to clean it thoroughly before starting.
6. Place the engine on a level-working platform to avoid fuel spilling out.
7. Make sure the fuel cap is tightened securely.
8. The exhaust muffler is very hot during running the engine even after the engine stops.
Never touch it, or you may get burns. Transport or store the engine with it cooled down entirely.
1

PARTS DESCRIPTION
The main parts of engine are located as follows (Fig.1):
2

Remote-Controlled Choke:
Steel wire nut
Choke Lever
Return Spring
Damping Nut
CONTROL CONNECTION OF REMOTE DISTANCE (OPTION)
The holes in levers of both the choke and throttle valve are used for mounting optioned steel wires. Illustrations
show how to mount a solid steel wire and a meshed steel wire. If choosing a meshed steel wire a return spring is
added.
If necessary, you may unscrew the
damping nut on the throttle valve
lever slightly when controlling the
throttle valve by a remote-
controlled steel wire.
Remote-Controlled Throttle:
3
4 mm Screw
Steel wire nut
Throttle valve lever
Snap ring
Accessory Options:
Stiff steel wire
Stiff steel wire

Pre-Operation Inspection
Engine Oil
Caution
● Engine oil is a key factor in deciding the engine's performance. Do not apply engine oil with additives or
2-stroke gasoline oil, as they haven't enough lubrication, which may shorten the engine's service life.
● Check the engine with it stopped on a level ground.
Engine oil recommended: SAE10W-30
As viscosity varies with regions and temperatures, so the
lubricant has to be selected in accordance with our
recommendation.
Check
1. Ensure that the engine is stopped on a level ground.
2. Remove the dipstick and clean it.
3. Reinsert the dipstick into the oil filler without
screwing in, and check oil level.
4. If the oil level is too low, add recommended engine
oil to the filler neck.
5. Reinstall the dipstick.
4
Dipstick
Upper Level Mark

AIR CLEANER
Dismantle the air cleaner housing and
check its filter element, make sure it is
clean and intact, if not or replace it.
CAUTION
Never run the engine without an air
cleaner, or severe wear of the engine
may occur.
FUEL AND FUEL TANK
1. Fuel
The engine must use unleaded gasoline with an octane number over 86. Using unleaded
gasoline will decrease the possibility of producing carbon deposits and prolong the engine's
service life. Never apply used or polluted gasoline or a mixture of gasoline and engine oil.
Make sure the fuel is free of dirt and water.
2. Gasoline Containing Alcohol
If you decide to use a gasoline containing alcohol (fuel blend), be sure its octane rating it at
least as high as that recommended. Use gasoline containing less than 10% ethanol or 5%. If
methanol content in the fuel blend exceeds 5%, it may have an effect on engine performance,
and may damage metal, rubber and plastic parts.
5
Air cleaner
housing
Filter
Element

CAUTION
Handle fuel with care, it can damage plastic and painted surfaces.
It is normal to hear an occasional light spark knock or pinging with the engine running
under heavy load.
Should spark knock or pinging be heard at a steady speed under normal load, change the
brand of gasoline; if it continues, consult your dealer for help, the engine may be
damaged.
3. Fuel Tank
Fuel tank capacity: 3.6 liters
4. Check
Remove the fuel filler
Cap and check fuel
level.
If the fuel level is too
low, refuel the tank. Remember adding fuel not over the fuel filter shoulder
6
Upper Fuel Level

WARNING
Gasoline is extremely flammable and is explosive under certain conditions. Refueling in
a well ventilated area with the engine stopped. Do not smoke and allow flames or sparks
in the area where gasoline is stored or where the fuel tank is refueled.
Do not overfill the tank (there should be no fuel in the filler neck). After refueling, make
sure the fuel tank cap is set back securely.
Be careful not to spill fuel when refueling. Spilled fuel or fuel vapor may ignite. If any
fuel is spilled, make sure the area is dry enough before starting the engine.
Avoid repeated or prolonged contact with skin or breathing of fuel vapor.
Keep out of reach of children.
7

STARTING OF THE ENGINE
1. Push the fuel cock to “ON.”
2. Push the choke lever to “CLOSE.”
NOTEIf the engine is hot, closing the
choke is unnecessary.
8

3. Move left the throttle lever a little.
4. Start the engine (Fig. 16).
a) Push the engine switch to “On”
b) Pull slightly the starting rope
handle up until feeling anti-action,
and then make a rapid pull.
CAUTION
Releasing the handle suddenly may make it hitting the engine. Release the handle slowly
conforming to its recoiling force.
9

OPERATION
1. Preheat the engine and push back the choke lever to “OPEN”
2. Set the throttle lever in proper position to ensure the engine runs at required velocity
10

Engine Oil Alarm
The engine oil alarm is designed to alarm the user the fact that the engine oil in the
crankcase is insufficient. Running with insufficient engine oil may damage the engine. When the
oil level in the crankcase is too low, the engine oil alarm will stall the engine automatically while
the engine switch is still at “ON”.
CAUTION
If the engine still fails to work, check the engine oil level first before go to other
check items.
Operating at high altitude
On highlands, the standard mixture ratio too rich and the engine performance may be
impaired while the fuel consumption may increase. This can be solved by replacing the main jet
of carburetor and adjusting the idle screw. If always at high altitude, ask your dealer to install the
jet after purchase. The engine power will decrease by about 3.5% with every 500 ft. in height;
even the proper main jet is used.
CAUTION
The engine equipped with the high alt main jet may be damaged seriously if run at
sea level due to its mixture ratio being too thin. Have your dealer reinstall the sea level jet
before running at sea level.
11

STOP
In an emergency, push the engine switch to “OFF” to stall the engine.
During normal operation, stop the engine in the following sequence:
1. Push the throttle valve lever to the right.
2. Push the engine switch to “OFF”
3. Turn the fuel lever to “OFF”
12
Throttle Valve Lever
Engine Switch
Low Speed
OFF
Engine Switch
OFF

EXHAUST CONTROL SYSTEM
With the engine running, carbon monoxide, nitrogen oxide, and hydrocarbons will be produced,
and in certain conditions, nitrogen oxide and hydrocarbons will react chemically with each other
to make smoke. Exhaust control is very important, carbon monoxide is toxic. DuroMax Power
Equipment decreases exhaust emissions by using lean carburetors and other devices in the engine
design.
To keep the exhaust of your engine within the standard exhaust emission values, pay attention to
the following:
I. MAINTENANCE
Maintain the engine in accordance with the Maintenance Schedule in the manual. The
maintenance schedule is based on normal use in normal conditions, if using under heavy load,
dusty or wet areas, or in high temperatures, more frequent maintenance will be necessary.
II. REPLACEMENT OF PARTS
We recommend that you use DuroMax Power Equipment OEM parts. Using aftermarket parts
may impair the exhaust control system effectiveness.
13

III. MODIFICATION
Modifying the exhaust control system may cause exhaust emissions to exceed statutory limit
values. Illegal modifications are as follows:
1. Dismantling or modifying any part of air inlet or outlet system.
2. Modify or remove speed-adjusting connection device or speed adjustment device to
result in the engine running outside the set parameters.
IV. PROBLEMS RELATED TO EXHAUST EMISSIONS
1. Difficultly starting or stopping the engine.
2. Unstable idle.
3. Black smoke and fuel consumption increase..
4. Poor ignition spark or backfiring.
5. Early or late ignition spark.
14

MAINTENANCE
I. MAINTENANCE SCHEDULE
To keep the engine in a sound condition, the user should maintain it according to the table below:
Every
Use
1st Use and/or
20 hrs.
3 months and/or
50 hrs.
6 months and/or
100 hrs.
Yearly and/or
300 hrs.
Engine oil
Oil level check
√
Replace
√
√
Reduction
gear oil (optional)
Oil level check
√
Replace
√
√
Air cleaner
Check
√
Clean
√①
√① *
Replace
√ **
Deposit cup
Clean
√
Spark plug
Clean/adjust
√
Replace
√
Spark Arrestor
Clean
√
Idling
Check-adjust
√②
Valve Clearance
Check-adjust
√②
Fuel tank & filter
Clean
√②
Fuel Line
Clean
Every two years (do replacement if necessary)
15