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WP10 Gas Engine
Key point of maintenance and assembly
Aug 2018
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2. 2
CONTENTS
1. Maintenance
2. Key point of assembly
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1.Maintenance—Specification of fuel, lubricating oil and coolant
•Natural Gas: at least 70% methane by volume or have a
heating value of 950-1100 BTUs per standard cubic foot
•LPG: minimum of 90% propane, maximum of 5% propylene,
and maximum 5% of other gases
Fuel
•Recommends using a straight weight or multi-weight low ash
content oil specifically formulated for Natural Gas Engines.
•Specific weight depends on operating temperatures: (10W-
30 : -25 to 30℃), (15W-40 : -20 to 40℃), (20W-50 : -15 to
45℃)
•API No. CH-4 or above are also recommended.
Oil
•recommends using a 50/50 mixture of fully formulated
Ethylene Glycol or fully formulated Propylene Glycol coolant
and distilled water
Coolant
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1.Maintenance—Maintenance schedule
Non-emergency
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1.Maintenance—Maintenance schedule
Emergency
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1.Maintenance—Daily check
1.Check engine oil level
2.Check coolant level
Caution : Never remove radiator
or top tank cap when coolant is
hot!
3. Check operation conditions
❖ Check hoses, clamps, pipes for loose
connection or leak.
❖ Check connectors for loose connection.
❖ Check harness for cut, short, corrosion
or abrasions.
❖ Check belt for loose or fraying.
❖ Assure battery voltage is ≥12v each.
4. Check oil pressure
Oil Pressure
Idle PSI KPa
Min 19 ≥130
Rated Speed
Min 50 350
Max 84 580
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1.Maintenance—Replace lubricating oil and oil filter element
Engine model Oil refill volume Material details
WP10
27~30L (7.1~7.9 Gal)
Recheck dipstick
2 filter elements and 2 O-rings
Replace oil filter element:
1. Drain oil completely.
2. Remove oil filters by the filter wrench and
remove O-rings.
3. Install new filter and O-ring by hand.(Apply a
thin coat of motor oil to o- ring before
installing)
4. Tighten filter until the rubber gasket contacts
base. Tighten additional 3/4 to 1 turn to seal..
5. Fill new oil and run engine for 5 minutes,
check for leaks.
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1.Maintenance—Adjust valve lash
1.The first piston is on the “TDC” of compression stroke
Valve lash (cold)
intake 0.5mm
exhaust 0.8mm
Fan
side
#1@TDC
(COMPRESSION STROKE)
INT EXH INT EXH INT EXH Flywheel
side
1 1 2 3 4 5
2.The number six piston is on the “TDC” of compression stroke
Fan
side
EXH INT EXH INT INT EXH #6@TDC
(COMPRESSION STROKE)
Flywheel
side
2 3 4 5 6 6
TDC mark
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CONTENTS
1. Maintenance
2. Key point of assembly
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2. Key point of assembly—Gear timing
1.Rotate the crankshaft to the TDC of first and sixth cylinder.
2.Rotate the camshaft and install the timing gear when the scale mark in timing
gear and “OT” scale mark in gear housing are aligning.
NOTE: Camshaft timing fastening bolts: Apply tighten
glue and tight to 45~45Nm.
1.Crankshaft gear 2.Intermediate gear
3.Camshaft gear 5.Signal generator gear
6.Oil pump intermediate gear
7.Oil pump gear
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2. Key point of assembly—Intermediate gear
“V” mark
Install intermediate gear:
1. The “V” mark should face to front (out side).
2. Bolts: Apply tighten glue and tight to (60±5)Nm, turn 90°, reach to
100~120Nm at the same time.
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2. Key point of assembly—Signal generator
1. Rotate the crankshaft to “OT” mark, make sure the first piston is on the top
dead center of compression stroke.
2. Install the signal generator and adjust angle of the fluted disc until its TDC mark
points at the center of the phase sensor and the predetermined ignition angle is
reached.
3. Tighten the locknut (80～100N·m) on the signal generator fluted disc.
Note: the correct value of the gap between the fluted disc and sensor is 0.8~1.5mm
1th piston@ TDC of
compression stroke
TDC mark points at the
center of phase sensor.
Fluted disc
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2. Key point of assembly—Connecting rod and piston
Key points:
1. The connecting rod oblique split are back to the piston notch.
2. The piston notch and oil nozzle should be in the same direction when install
the connect rod and piston combinations.
3. The torque of connecting rod bolt is :120N·m + (90±5°), (Reach 170 to
250N·m at the same time)
NOTE: 1.The connecting rod bolts can’t be re-used.
2. The opening mouth of piston rings should not overlap.
Adjust the angle of piston
rings to make sure the
opening not overlap.
1.The oblique split
are back to the
piston notch.
2. The piston notch
should be in the
same direction with
oil nozzle
Piston
notch
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2. Key point of assembly—Main bearing bolt
Main bearing bolts:
The first time 80Nm, the second time 250Nm. Required sequence of
tightening as below
Note: the oil groove on the thrust plate should face to crankshaft.
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2. Key point of assembly—Cylinder head bolts
Cylinder head bolts and nuts:
1. Align the cylinder head with the cylinder block. Apply a proper amount of clean lubricating oil to the
threads and pressure-bearing surfaces of shoulders of the main bolts of cylinder head and the
shouldered nuts. Install the main bolts to the cylinder head. Install the clamping blocks and nuts to
the auxiliary bolts of cylinder head.
2. Tighten the main bolts and nuts of auxiliary bolts of cylinder head to the torque of (30~50) Nm.
3. Tap the clamping blocks so that they descend in place.
4. Tighten the nuts of auxiliary bolts in the sequence to the torque of 100N·m.
5. Tighten the main bolts in the sequence to the torque of 200N·m.
6. Tighten the nuts of auxiliary bolts in the sequence by 90º. Then make marks on the nuts.
7. Tighten the main bolts in the sequence by 90º. Then make marks on the bolts.
8. Tighten the nuts of auxiliary bolts in the sequence by another 90º to the torque of (120~160) Nm.
9. Tighten the main bolts in the sequence by another 90º to the torque of (240~340) Nm.
10. The cylinder head bolts and nuts shall be tightened according to the order given by Illustration
below, in which, those numbering 1-21 are nuts of auxiliary bolt, while those numbering 22-45 are
main bolts of cylinder head
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2. Key point of assembly—Flywheel housing
Flywheel housing bolts:
1. Apply the lubricating oil on the contact surface and thread of bolts.
2. Tighten torque: 100~140Nm and tighten sequence as below.
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2. Key point of assembly—
Engine Fastener Torque Specifications
Fastener’s Name Bolt Specification
Tightening torque (N·m) + further turned
angle (°)
Permissible times of
repeat used
Main bearing M18-10.9
The first time 80N·m, the second time
250~280N·m (See illustration13)
2
Connecting rod M14x1.5-12.9
120N·m + (90±5°), (Reach 170 to 250N·m at
the same time)
0
Cylinder head M16-12.9
200N·m +2x (90±5°), required sequence of
tightening (See illustration14), (Reach 240 to
340N.m at the same time)
3
Flywheel M14x1.5
60N·m +2x(90±5°), (Reach 230 to 280N·m at
the same time)
2
Flywheel housing 110 to 140N·m 2
Camshaft gear M8-12.9 40 to 45N·m
Exhaust manifold M10 50 to 70N·m 2
Intake manifold M10 45+5N.m -
Damper M10-10.9 65 to 70N·m -
Spark-plug M14x1.25 (25 to 28) N·m -
UEGO sensor M18x1.5 40N.m±5N·m -
Water temperature
sensor
M14x1.5 25N.m±5N·m -
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