DUROMAX XP12000EH User manual

REV: XP12000EH-03162023
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.
*Gasoline & Propane Tank Not Included
XP12000EH
SERVICE MANUAL
5800 Ontario Mills Pkwy
Ontario, CA 91764 USA
www.duromaxpower.com
Call our Customer Care Team Toll Free 8-5 pm PST Mon-Fri
844-DUROMAX

CONTENTS
1.
Generator Components................................................................................................. 6
Generator Components
4.
Specications................................................................................................................. 30
Torque Values ............................................................................................................... 31
Specications
3.
Troubleshooting............................................................................................................ 33
Changing/Inspecting the Carbon Brushes................................................................. 34
Changing/Inspecting the AVR ...................................................................................... 36
Troubleshooting
2.
Maintenance Schedule................................................................................................... 8
Break-In Period ............................................................................................................... 9
High Altitude Operation ................................................................................................. 9
Changing the Carburetor Main Jet.............................................................................. 10
Checking the Oil ............................................................................................................ 14
Changing the Oil............................................................................................................ 15
Cleaning the Air Filter ................................................................................................... 16
Spark Plug Maintenance .............................................................................................. 18
Emptying the Gas Tank ................................................................................................ 20
Cleaning the Fuel Filter Cup......................................................................................... 22
Transporting the Generator ........................................................................................ 23
Storing the Generator for Same Day Use .................................................................. 24
Storing the Generator for Use Within 30 Days.......................................................... 25
Storing the Generator for Longer Than 30 Days....................................................... 26
Check and Adjust Valve Clearance.............................................................................. 28
Maintenance and Care

CONTENTS
5.
Common Engine Parts................................................................................................... 39
Wiring Diagram .............................................................................................................. 46
Generator Diagrams
6.
Maintenance Log............................................................................................................ 47
Maintenance Log

GENERATOR COMPONENTS
6
2. Choke Lever
1. Air Filter
10. Volt Meter
8. 120V 3-Prong
Receptacle
21. 50A Receptacle
20. 120V 3-Prong
Twist Lock
6. 120/240V 4-Prong
Twist Lock
23. Power Boost
5. Circuit Breaker
22. Idle Control
7. Ground
Terminal
9. Battery
12. Oil Fill and Dipstick
13. Engine Switch
14. Recoil Start
11. 12V DC
Charging Posts
1. Air Filter - a removable, cleanable, oiled, element that cleans the air going into the engine.
2. Choke Lever - Allows the airow into the carburetor to be restricted to assist in starting the
engine.
3. Fuel Gauge - Indicates the amount of fuel in the gasoline tank.
4. Fuel Cap - Allows access to ll the gasoline tank.
5. Circuit Breaker - Resettable switch that protects the generator from electrical overload.
6. 120/240V 4-Prong Twist Lock - Use to connect electrical devices that run 120 or 240 Volt, 60Hz,
single phase, AC current (NEMA L14-30).
7. Ground Terminal - Connect a ground wire here to properly ground the generator.
8. 120V 3-Prong Receptacle - Use to connect electrical devices that run 120 Volt, 60 Hz, single
phase, AC current (NEMA 5-20).
9. Battery - 12V DC battery that powers the electric start system.
10. Volt Meter - Provides reading of voltage output.
11. 12V DC Charging Posts – DC output for charging batteries or running small DC powered items.
12. Oil Fill and Dipstick - Use to add or check the oil.
16. Fuel Valve
18. Muer

4. Fuel Cap
15. Fuel Filter Cup
18. Muer
17. Spark Plug
19. Propane Connector
3. Fuel Gauge
13. Engine Switch – 3 Position Switch to “START”, “RUN”, or turn “OFF” the generator.
14. Recoil Start – Easy pull recoil start to start the engine without the electric start.
15. Fuel Filter Cup - Traps dirt and debris in gasoline before it enters the engine.
16. Fuel Valve - On/O valve that allows fuel into the engine.
17. Spark plug – Provides ignition to the engine.
18. Muer – Reduces engine emissions and reduces noise.
19. Propane Connector – Connects the LPG tank to the LPG Regulator. (Intended for use with a
LPG source of 3 PSI or more.
20. 120V 3-Prong Twist Lock - Use to connect electrical devices that run 120 Volt, 60 Hz, single
phase, AC current (L5-30).
21. 50A Receptacle - Use to connect electrical devices that run 120 or 240 Volt, 60Hz, single phase,
AC current (NEMA 14-50).
22. Idle Control - Runs engine at reduced speed when no load is present to save on fuel and
reduce noise levels.
23. Power Boost - Double the 120V power for appliances & RVs.
7

MAINTENANCE AND CARE
8
Proper routine maintenance of your generator is essential for safe, economical, and trouble-free
operation. It will also help reduce air pollution.
Maintenance Schedule
Remember that this schedule is based on the assumption that your machine will be used for its
designed purpose. Sustained high-load, high-temperature operation, or use in unusually wet or
dusty conditions, will require more frequent service.
SERVICE
EVERY USE
1ST MO. OR
8 HRS.
(BREAK IN)
EVERY 3 MO. OR
50 HRS. OF
HEAVY USE
EVERY 6 MO.
OR 100 HRS. OF
NORMAL USE
EVERY 12 MO. OR
300 HRS.
EVERY 3 YRS. OR
500 HRS.
ENGINE OIL CHECK CHANGE CHANGE CHANGE
AIR CLEANER CHECK CHECK CHANGE CHANGE
SEDIMENT
CUP
CLEAN CLEAN
SPARK PLUG CLEAN /
ADJUST
CLEAN /
ADJUST
SPARK
ARRESTOR
CHECK CLEAN
IDLE SPEED CHECK /
ADJUST
VALVE
CLEARANCE
CHECK /
ADJUST
FUEL TUBE CHECK CHECK /
REPLACE
FUEL TANK /
FILTER
CLEAN
COMBUSTION
CHAMBER
CLEAN
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 o before you begin any maintenance or repairs.
●Let the engine and exhaust system cool before touching.
●To reduce the possibility of re or explosion, be careful when working around
gasoline. Use only a nonammable solvent, not gasoline, to clean parts. Keep
cigarettes, sparks, and ames away from all fuel-related parts.

9
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 generator for the rst 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 rst 6-8 hours keep the generator load under 50%
for optimal results.
●Check and clean the air lter if necessary after the break-in period.
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 diers from that at which this engine was certied, for extended periods of
time, may increase emissions. High altitude performance can be improved by specic modications to
the carburetor. If you always operate your engine at altitudes above 3,000 feet (900 meters), have a dealer
perform this carburetor modication. This engine, when operated at high altitude with the carburetor
modications for high altitude use, will meet each emission standard throughout its useful life. Even with
carburetor modication, engine horsepower will decrease by about 3.5% for each 1,000-foot (300-meter)
increase in altitude. The eect of altitude on horsepower will be greater than this if no carburetor
modication is made.
When the carburetor has been modied for high altitude operation, the air/fuel mixture will be too lean for
low altitude use. Operation at altitudes below 3,000 feet (900 meters) with a modied carburetor may cause
the engine to overheat and result in serious engine damage.
Note: Jet kits available for purchase upon request, please contact us at 844-DUROMAX to set up your
parts order.
Altitude Range Jet Kit Part Number
3,000 ft. - 6,000 ft. DJ190FD-14100-3KJS
6,000 ft. - 8,000 ft. DJ190FD-14100-6KJS

MAINTENANCE AND CARE (CONTINUED)
Changing the Carburetor Main Jet
Unclip the cover and element
Unclip and remove the air lter cover, then remove the air
lter elements.
NOTE: Carburetor should be drained of all gasoline prior
to servicing.
1.
Unbolt element holder
Remove air lter nuts
Remove air lter bracket nut
Remove all 6 bolts of the element holder with an 8mm socket
wrench, then remove the element holder.
Remove the 2 front facing nuts connecting the air lter to the
carburetor.
Remove the nut attaching the bottom air lter bracket located
behind the air lter housing.
2.
3.
4.
10

11
Remove carburetor bowl
Remove the carburetor bowl from carburetor.
8.
Remove air lter hose
Remove air lter hose clip with pliers and remove hose from
behind air lter.
5.
Remove carburetor solenoid
Remove both Phillips screws attaching carburetor solenoid
with a standard Phillips screwdriver.
6.
7. Remove carburetor bowl bolt
Remove the carburetor bowl bolt located under the solenoid
with a 14 mm socket wrench.

12

Changing the Carburetor Main Jet (Continued)
Determine main jet location
The carburetor jet is located inside the center metal tube of
the carburetor.
9.
Remove main jet
Install new main jet
Reassemble generator
Remove the main jet with a at head screwdriver. If necessary
gently tap the carburetor to allow the jet and emulsion tube to
fall out.
Place emulsion tube located above the jet back into the
carburetor tube in the same position, then install the new
main jet.
Once the new jet is installed, reverse the above instructions
to reassemble carburetor and reinstall air lter assembly.
10.
11.
12.
MAINTENANCE AND CARE (CONTINUED)
13

MAINTENANCE AND CARE (CONTINUED)
14
Model Number XP12000EH
Engine Oil Capacity 40.5 . oz (1.2 L)
Checking the Oil
Check the oil
The generator is equipped with an automatic shuto 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 sucient amount.
To check the oil level:
a. Make sure the generator is on a level surface.
b. Unscrew the oil ller/dipstick cap.
c. With a dry cloth, wipe the oil o of the stick on the
inside of the cap.
d. Insert the dipstick as if you were replacing the
cap and then remove it again. There should now be
oil on the stick. If there is no oil on the stick, or oil
only at the very end of the stick, you should add
oil until the engine crankcase is lled (see “Adding
Oil” portion of the “Maintenance” section).
e. The oil will be visible in the oil ll spout when full.
f. Be sure to replace the cap when nished checking
oil.

Replace drain plug
Replace the oil drain plug and tighten with a 12 mm hex
wrench.
CAUTION: Worn out or dirty oil does not cool the
generator 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.
3.
Remove drain plug
Using a 12 mm hex wrench, unscrew the oil drain plug, which
is located on the crankcase underneath the oil ller/dipstick
cap.
Allow all the oil to drain from the generator.
1.
Drain oil
Drain oil into an approved oil disposal container. Contact
your local auto parts store for information on oil disposal.
2.
15
Changing the Oil

MAINTENANCE AND CARE (CONTINUED)
16
Remove the lter cover
Remove lter
Clean out lter casing
Release the clips on the top and bottom of the cover and
remove the lter cover.
Remove the sponge-like elements from the casing.
Wipe the dirt from inside the empty air cleaner casing.
1.
2.
3.
Routine maintenance of the air cleaner helps maintain proper
airow 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.
Cleaning the Air Filter

17
Replace elements in casing
Replace the sponge-like elements in the air cleaner casing and
replace the cover.
7.
Wash cleaner element
Wash the sponge-like elements in household dish detergent
and warm water.
4.
Dry cleaner element
Pat dry on a dry cloth and allow the elements to dry completely.
5.
6. Addengine oilto elements
Soak the dry elements in a small amount of engine oil. Ring
out any excess oil.

Spark Plug Maintenance
MAINTENANCE AND CARE (CONTINUED)
18
The spark plug is important for proper engine operation.
A good spark plug should be intact, free of deposits, and
properly gapped.
Remove spark plug cap
Remove spark plug
Inspect spark plug
Pull on the spark plug cap to remove it.
Unscrew the spark plug from the generator using the spark
plug wrench included with this product.
Visually inspect the spark plug. If it is cracked or chipped,
discard and replace it with a new spark plug. We recommend
using an F6RTC spark plug such as NGK BPR6ES.
1.
2.
3.
CAUTION: Improper maintenance may cause reduced fuel economy, misres,
trouble starting, or damage to the spark plug threads.
SPARK PLUG
CONSULT MANUAL
BEFORE REMOVING

19
Measure plug gap
Measure the plug gap with a gauge. The gap should be 0.7-0.8
mm (0.028-0.031 in).
4.
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.
5.
Install spark plug
Replace spark plug cap
Screw the spark plug back into its place on the generator
using the spark plug wrench.
Replace the spark plug cap.
6.
7.

Emptying the Gas Tank
MAINTENANCE AND CARE (CONTINUED)
20
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.
If you have been using gasoline in your generator, before
storing your generator for extended periods of time you
should drain your generator fuel tank of gasoline.
Shut fuel valve OFF
Remove fuel lter cup
Empty fuel lter cup
Turn the fuel valve to the “OFF” position.
Remove the fuel lter cup (see “Removing the Fuel Filter Cup”
later in this section).
Empty the fuel lter cup of any fuel.
1.
2.
3.