Power House PH3300i User manual

PH3300i Digital Inverter Generator
SERVICE MANUAL
POWERHOUSE ®

2 PH3300i SM, Rev. 2017-01-20
PREFACE
This manual covers the construction, function and servicing procedure of the POWERHOUSE
®
PH3300i
generator, certificated by CARB.
Careful observance of these instructions will result in better, safer service work.
All information, illustrations, directions and specifications included in this publication are based on the latest
product information available at the time of approval for printing. KeystoneAutomotive Operations, Inc.
reserves the right to make changes without incurring any obligation whatsoever. No part of this publication
may be reproduced without written permission.
Pay special attention to statements preceded by the following words:
Indicates a strong possibility of severe personal injury or death if instructions are not
followed.
Indicates a possibility of personal injury or equipment damage if instructions are not
followed.
Gives helpful information.
Please read and review the PH3300 Owner’s Manual before using this Service
Manual.

3 PH3300i SM, Rev. 2017-01-20
CONTENTS
PREFACE...........................................................................................................................................................2
CONTENTS........................................................................................................................................................3
1. GENERAL SPECIFICATIONS.......................................................................................................................6
1.1 Specifications............................................................................................................................................6
1.2 Characteristics..........................................................................................................................................7
1.3 Wiring Diagram.........................................................................................................................................8
2. SERVICE INFORMATION..............................................................................................................................9
2.1 The Importance of Proper Servicing.........................................................................................................9
2.2 Important Safety Precautions...................................................................................................................9
2.3 Servicing Rules.......................................................................................................................................10
2.4 Electrical Precautions.............................................................................................................................10
2.5 Engine Serial Number and Bar Code Number.......................................................................................11
2.6 Engine Maintenance Specifications.......................................................................................................11
2.7 Alternator Electrical Specifications (Stator/Rotor Windings)..................................................................13
2.8 Torque Values.........................................................................................................................................13
3. MAINTENANCE...........................................................................................................................................14
3.1 Maintenance Schedule...........................................................................................................................14
3.2 Battery Maintenance...............................................................................................................................15
3.2.1 12V 10AhAGM Starting Battery......................................................................................................15
3.2.2 3.6V Li-ion Ignition Batteries............................................................................................................15
3.3 Checking the Oil Level............................................................................................................................16
3.4 Changing Oil...........................................................................................................................................17
3.5 Air Filter Inspection and Cleaning...........................................................................................................18
3.6 Spark Plug Inspection and Cleaning......................................................................................................19
3.7 Valve Clearance Inspection and Adjustment..........................................................................................20
3.8 Evaporation Control System...................................................................................................................21
3.9 Replacing Fuel Filter...............................................................................................................................22
3.10 Spark Arrestor.......................................................................................................................................23
4. TROUBLESHOOTING.................................................................................................................................24
4.1 Starter Does Not Crank..........................................................................................................................25
4.2 Hard Starting...........................................................................................................................................26
4.2.1 Pre-Start Throttle Location...............................................................................................................27
4.3 Cylinder Compression Check.................................................................................................................28
4.4 Ignition System.......................................................................................................................................29
4.4.1 Checking for Spark ..........................................................................................................................30
4.4.2 Ignition Coil/TriggerAssembly Inspection........................................................................................31
4.4.3 Ignition Switch Inspection................................................................................................................32
4.5 Oil Level Sensor Fails to Stop Engine with Low Oil...............................................................................33
4.5.1 Checking the Low Oil Sensor..........................................................................................................34
4.6 Engine Stops Running............................................................................................................................35

4 PH3300i SM, Rev. 2017-01-20
4.6.1 Fuel Pump Testing...........................................................................................................................36
4.7 Engine Speed Cannot Increase or is Hunting........................................................................................37
4.8 Engine Speed Too High..........................................................................................................................37
4.9 No or LowAC Output..............................................................................................................................38
4.10 Measuring Stator Main Output Voltage While Running .......................................................................39
4.11 No DC OutputAt Battery Charge Receptacle......................................................................................40
4.12 Starting Battery Will Not Charge ..........................................................................................................40
4.13 Voltage Regulator Testing.....................................................................................................................41
4.14 Engine Runs-on or Backfires After Being Turned Off...........................................................................42
4.15 Engine Will Start Then Shut Down.......................................................................................................42
5. REPAIR ........................................................................................................................................................43
5.1 Carburetor...............................................................................................................................................43
5.1.1 Removal / Installation of Carburetor................................................................................................43
5.1.2 Throttle Control –Step Motor ..........................................................................................................44
5.1.3 Backfire Prevention Solenoid (BFP)................................................................................................46
5.1.4 Manual Choke Assembly .................................................................................................................47
5.1.5 HighAltitude Jet...............................................................................................................................48
5.2 Control Panel..........................................................................................................................................49
5.2.1 Disassembly / Installation................................................................................................................49
5.3 Outer Generator Housing.......................................................................................................................50
5.3.1 Disassembly / Installation................................................................................................................50
5.4 Recoil Starter..........................................................................................................................................51
5.4.1 Disassembly / Reassembly..............................................................................................................51
5.5 Starter motor...........................................................................................................................................52
5.5.1 Starter Testing..................................................................................................................................52
5.5.2 Starter Removal / Replacement.......................................................................................................53
5.6 Starter Relay...........................................................................................................................................54
5.6.1 Testing Starter Relay on Generator.................................................................................................54
5.6.2 Bench Testing the Starter Relay......................................................................................................55
5.7 Intake Fan Cover....................................................................................................................................56
5.8 Ignition Coil/TriggerAssemblyAdjustment / Replacement ....................................................................58
5.9 Stator and Rotor.....................................................................................................................................59
5.9.1 Stator Inspection..............................................................................................................................59
5.9.2 Stator Removal and Reassembly....................................................................................................60
5.10 Inverter Inspection / Adjustment / Replacement ..................................................................................61
5.10.1 Inverter Removal / Preparation for Adjustment..............................................................................61
5.10.2 Inverter Adjustment / Replacement ...............................................................................................62
5.10.3 Inverter Ignition Power...................................................................................................................63
5.11 Muffler Removal / Replacement...........................................................................................................64
5.12 Engine Exploded View..........................................................................................................................65
5.13 Cylinder Head / Valves.........................................................................................................................68
5.13.1 Cylinder Head Removal.................................................................................................................68
5.13.2 Cylinder Head Disassembly and Reassembly ..............................................................................69

5 PH3300i SM, Rev. 2017-01-20
5.13.3 Valve and Spring Inspection..........................................................................................................70
5.14 Crankshaft / Camshaft / Piston.............................................................................................................71
5.14.1 Disassembly and Reassembly.......................................................................................................71
5.14.2 Alignment of Timing Marks.............................................................................................................72
5.14.3 Camshaft Inspection......................................................................................................................73
5.14.4 Piston / Connecting Rod................................................................................................................74

6 PH3300i SM, Rev. 2017-01-20
1. GENERAL SPECIFICATIONS
1.1 Specifications
Dimensions And Weights
Model
PH3300i
Overall Length
603mm (23.75”)
Overall Width
476mm (18.75”)
Overall Height
546mm (21.25”)
Net Weight
61 kg (134 lbs.)
Engine
Model
XG-177F
Type
4-stroke,OHV, single cylinder, Gasoline engine
Displacement
270cc
Bore x stroke
77 × 58
Maximum horsepower
6.8
Compression ratio
9.2:1
Cooling system
Forced air-cooled
Ignition system
Electronic
Spark plug
F7RTC
Carburetor
Horizontal, Float type
Air cleaner
Semi-dry type
Governor
Electronic control
Lubrication system
Splash
Lube oil
SAE 10W-30 (SF/SG grade ) above 0°C (32°F);
SAE 0W-30/0W-40 below 0°C (32°F)
Oil capacity
1.0 L (35 oz.)
Starting system
Electric & Recoil
Stopping system
Primary circuit ground
Fuel used
Automotive unleaded gasoline
Alternator
Alternator type
Multi pole rotation type
Alternator structure
Self-ventilation drip-proof type
Excitation
Self-excitation (Magnet type)
Phase
Single phase
Rotating direction
Clockwise (Viewed from the generator)
Frequency regulation
AC-DC-AC conversion (Inverter type)

7 PH3300i SM, Rev. 2017-01-20
1.2 Characteristics
Model
PH3300
Maximum output AC
3300W
Rated output AC
3200W
Rated frequency
60HZ
Rated voltage AC
120V
Rated voltage DC
12V
Rated current AC
26.7A
Rated current DC
8.3A
Power factor
1.0cosφ
Voltage variation rate Momentary
Average
Average time
10%max.
1.5%max.
3 sec. max.
Voltage stability
±1%
Frequency variation rate Momentary
Average
Average time
1%max.
1%max.
1 sec. max.
Frequency stability
±0.1%
Insulation resistance
10MΩmin.
AC circuit protector
20A and 30A (120V)
DC circuit protector
10A
Fuel tank capacity
16.3L (4.3 gal)
Continuous running time
(at rated load ½ at ¼ load)
10.9 hours / 16.6 hours
Noise level (Zero load to full load)
63-78 dB @ 7m (23’)

8 PH3300i SM, Rev. 2017-01-20
1.3 Wiring Diagram

9 PH3300i SM, Rev. 2017-01-20
2. SERVICE INFORMATION
2.1 The Importance of Proper Servicing
Proper servicing is essential to the safety of the operator and the reliability of the engine.Any error or
oversight made by the technician while servicing can easily result in faulty operation, damage to the
engine and injury to the operator.
Improper servicing can cause an unsafe condition that can lead to serious injury
or death.
Follow the procedures and precautions in this service manual carefully.
Some of the most important precautions are given below. However, we cannot
warn of every conceivable hazard that can arise in performing servicing or repairs.
Only you can decide whether you should perform a given task.
Failure to follow maintenance instructions and precautions can cause you to be
seriously injured or killed. Follow the procedures and precautions in this service
manual carefully.
2.2 Important Safety Precautions
Be sure you have a clear understanding of all basic shop safety practices. Wear appropriate clothing
and personal protective equipment. When performing servicing or repairs, the below CAUTION steps
must be followed:
Read the instructions before you begin any servicing, be sure you have the
equipment and skills required to perform the tasks safely.
Be sure that the engine is off before you begin any servicing or repairs.■
To avoid carbon monoxide poisoning from engine exhaust, make sure there is
adequate ventilation whenever you run the engine.
To avoid burns from hot engine parts and hot exhaust, let the engine and exhaust
cool before touching them.
To avoid injury, use caution when working around moving parts.■
Do not run the engine unless the Service Manual instructs you to do so. When
the engine is running, keep your hands, fingers and clothing away from moving
parts.
To reduce the possibility of a fire or explosion, be cautious when working around
gasoline. Use only a nonflammable solvent and not gasoline to clean parts. Keep
all cigarettes, sparks and flames away from fuel and all fuel-related parts.

10 PH3300i SM, Rev. 2017-01-20
2.3Servicing Rules
1. Use genuine POWERHOUSE® or POWERHOUSE® recommended parts and lubricants or their
equivalents. Parts that do not meet POWERHOUSE® design specifications may damage the
engine.
2. Always install new gaskets, O-rings, etc. when reassembling.
3. When tightening bolts or nuts, begin with larger-diameter or inner bolts first and tighten to the
specified torque diagonally, unless a particular sequence is specified.
4. Clean parts in cleaning solvent upon disassembly. Lubricate any sliding surfaces before
reassembly.
5. After reassembly, check all parts for proper installation and operation.
6. Many screws used in this machine are self-tapping. Be aware that cross-threading or over
tightening these screws will strip the threads and damage the hole.
7. Use only metric tools when servicing this engine. Metric bolts, nuts and screws are not
interchangeable with non-metric fasteners. The use of incorrect tools and fasteners will damage
the engine.
2.4 Electrical Precautions
1. Hold the connector body to disconnect the connector. Do not disconnect by pulling the wire
harness. To disconnect the locking connector, be sure to unlock first, and then disconnect.
2. Check the connector terminals for bent pins, excessive stretching, missing terminals or other
abnormalities before connecting the connector.
3. To connect, insert the connector completely into the receptacle. If the connector is a locking type,
be sure that it is locked securely.
4. Check the connector cover for cracks or other damage and make sure the connector female
terminal fits snugly into the connector. Then, connect the connector securely. Check the
connector terminal for rust. Remove any rust using a fine emery paper or equivalent material
before connecting the connector.
5. Secure the harness clips in the specified locations on the frame and clamp the wire harnesses.
6. Clamp the wire harnesses securely so that they do not interfere with rotating parts, moving parts
or hot parts.
7. Route and connect the wire harnesses as shown in the Service Manual. Be sure that the
harnesses are not loose, twisted or pulled tight.
8. Route the wire harnesses properly so that they do not come in contact with sharp edges or
corners or the ends of any bolts or screws.
9. If a wire harness contacts the ends of any bolts or screws or sharp edges or corners, protect that
part of the harness by wrapping insulating tape on the sharp surface. If the wire harness has a
grommet, install the grommet securely.
10. Take care not to pinch the wire harnesses during installation of a part. If a wire harness has
damaged insulation, repair by winding with the electrician’s insulating tape.
11. Before using test equipment, carefully read the manufacturer’s instructions and follow the
instructions in this Service Manual. Be sure that the test equipment battery is fully charged and
verify that the unit is operating correctly before you begin testing.

11 PH3300i SM, Rev. 2017-01-20
2.5 Engine Serial Number and Bar Code Number
The generator bar code number (BCN) and the engine serial number (ESN) identify your particular
unit and are necessary when ordering parts and accessories. These two numbers are used by your
dealer and Keystone Automotive Operations for warranty administration and must be supplied before
any work can be done.
The BCN is found in three locations:
1. On the side of the generator, lower left of the oil access door.
2. On the back of the Owner’s Manual.
3. On the outside of the shipping carton.
The engine serial number can be found stamped on the engine block above the oil dipstick. It is
visible when the engine oil access cover is removed (Fig. 1).
2.6 Engine Maintenance Specifications
Part
Item
Specification
Service limit
Engine
Maximum speed without load
3600±100rpm
—
Cylinder
Sleeve I.D.
77.000-77.020mm
(3.0315”-3.0323”)
77.105mm
(3.0356”)
Piston
Skirt O.D.
76.960-76.980mm
(3.0299”-3.0307”)
76.85mm
(3.0256”)
Pin bore I.D.
18.002-18.008mm
(0.7087”-0.07090”)
18.05mm
(0.7106”)
Piston pin
O.D.
17.994-17.000mm
(0.7084”-0.7087”)
17.95mm
(0.7067”)
Piston ring
1st ring
Height
1.97-1.99mm
(0.0776”-0.0783”)
1.87mm
(0.0736”)
Ring side clearance
0.02-0.06mm
(0.001”-0.002”)
0.15mm
(0.006”)
Ring end clearance
0.15-0.25mm
(0.006”-0.010”)
1.0mm
(0.040”)
Width
3.4-3.6mm
(0.134”-0.142”)
3.2mm
(0.126”)
Fig. 1

12 PH3300i SM, Rev. 2017-01-20
2.5 Engine Maintenance Specifications (continued)
Part
Item
Specification
Service limit
Piston ring
(continued)
2nd ring
Height
1.97-1.99mm
(0.0776”-0.0783”)
1.87mm
(0.0736”)
Ring side clearance
0.02-0.06mm
(0.001”-0.002”)
0.15mm
(0.006”)
Ring end clearance
0.15-0.25mm
(0.006”-0.010”)
1.0mm
(0.040”)
Width
3.40-3.60mm
(0.134”-0.142”)
3.20mm
(0.126”)
Oil ring
Height
3.40-3.60mm
(0.134”-0.142”)
3.20mm
(0.126”)
Ring side clearance
0.03-0.18mm
(0.001”-0.007”)
0.24mm
(0.009”)
Ring end clearance
0.20-0.50mm
(0.008”-0.020”)
1.0mm
(0.040”)
Width
2.3-2.7mm
(0.090”-0.110”)
2.2mm
(0.087”)
Connecting
rod
Small end I.D.
18.006-18.017mm
(0.7089”-0.7093”)
18.08mm
(0.712”)
Big end I.D.
33.020-33.033mm
(1.3000”-1.3005”)
33.09mm
(1.303”)
Crankshaft
Crank pin O.D.
32.967-32.980mm
(1.2979”-1.2984”)
32.90mm
(1.295”)
Valves
Valve
clearance
IN
0.10±0.02mm
(0.004” ±.001”)
---
EX
0.15±0.02mm
(0.006” ±.001”)
---
Stem O.D.
IN
6.46-6.48mm
(0.254”-0.255”)
6.40mm
(0.2520”)
EX
6.455-6.470mm
(0.2541”-0.2547”)
6.40mm
(0.2520”)
Guide I.D.
IN/EX
6.500-6.530mm
(0.2559”-0.2571”)
6.56mm
(0.2583”)
Seat width
IN/EX
0.8mm (0.03”)
1.8mm (0.07”)
Valve spring
Free length
IN/EX
39.1mm (1.54”)
37.5mm (1.48”)
Cam Lobe
Cam Lobe height
31.700-31.780mm
(1.2480”-1.2512”)
31.00mm
(1.2205”)
Carburetor
Main jet
0.79mm (.0310”)
—
Float height
12
—
Pilot screw opening (Fixed)
N/A
—
Spark plug
Gap
0.6-0.7mm
(0.024”-0.028”)
—
Ignition coil
Resistance
Primary side
1.4-2.0 Ω
—
Second side
11.0-15.0kΩ
—
Trigger coil
Resistance
113-122 Ω
—

13 PH3300i SM, Rev. 2017-01-20
2.7 Alternator Electrical Specifications (Stator/Rotor Windings)
Part
Item
Wire color
Specification(Ω)
DC winding
Resistance
blue－blue
0.02-0.06
Sub winding
Resistance
white－white
0.10-0.16
Main winding
Resistance
black－black－black
0.25-0.35
2.8 Torque Values
Item
Specification
Tightening torque
ft-lb
N∙m
Connection rod bolt
M8x40
21-24
28-32
Spark plug
M12x1x13
9-11
12-15
Crankcase cover
M8x35
21-23
28-31
Flywheel nut
M16x1.5
66-74
90-100
Standard torque
M5 Bolt, nut
4-6
6-8
M6 Bolt, nut
6-7
8-10
M8 Bolt, nut
15-17
18-22
M10 Bolt, nut
41-44
55-60
Use standard torque values for fasteners that are not listed in this table.■

14 PH3300i SM, Rev. 2017-01-20
3. MAINTENANCE
3.1 Maintenance Schedule
Notes:
(1) Log Hours of operation to determine proper maintenance
(2) Service more frequently when used in dusty areas.
(3) These items should be serviced by an authorized dealer unless the owner has the proper tools
and is mechanically proficient.
Item
Maintenance
Procedure
Regular Service period. Perform at every indicated month
or operating hour interval, whichever occurs first.
Each Use
1st Month
or 4 to 6
Hours
Every 3
Months or
50 HRS
Every 6
Months or
100 HRS
1x per Year
or 300 HRS
Engine Oil
Check
O
Change
O
O
Air cleaner
Check
O
Clean
O(2)
Spark Plug
Clean - adjust
O
Spark Arrester
Clean
O
Fuel Filter
Check
O
Replace
O(2)
Valve clearance
Check - Adjust
O(3)
Fuel tank & strainer
Clean
O(2)
Fuel line
Check
Every 2-years (Replace as necessary)
12V 10Ah AGM
Starting Battery
Clean - Charge
Charge monthly during long term storage.
Check terminals for corrosion monthly, clean as needed.
Expected battery life is 2 years, but can be affected by operating environment.
3.6V Li-ion
Ignition Batteries
Inspect - Replace
Check the voltage and inspect the terminals monthly during long term storage.
The voltage should be 3.2-4.0V depending on the temperature. If the voltage
is low, or the terminals are corroded, replace the Li-ion batteries.
Expected battery life is 2 years, but can be affected by operating environment.

15 PH3300i SM, Rev. 2017-01-20
3.2 Battery Maintenance
It is recommended that the starting battery and ignition batteries be fully charged before starting any
diagnostic work on the generator.
3.2.1 12V 10Ah AGM Starting Battery
This generator comes equipped with 12V, 10Ah,AGM starting battery located behind the
maintenance door. This battery is charged by the generator during periods of frequent usage; if
the battery is not holding a charge refer to (section 4.12). During periods of infrequent use it is
recommended that the battery be charged monthly.A TC2-P plug-in trickle battery charger or
equivalent is recommended. The battery will be damaged by improper charging or overcharging.
If this battery appears swollen or damaged, replace it. Do not replace this battery with one that
has less than 10Ah capacity. It is recommended that the battery be replaced with the exact OEM
replacement battery.
3.2.2 3.6V Li-ion Ignition Batteries
This generator comes equipped with two Panasonic NCR18650B 3.6V Li-ion ignition batteries
which have a 3350mAh capacity and protective circuitry (Fig. 2). They are located in a tray,
mounted on the air cleaner cover. They can be accessed by removing the control panel and
carefully letting it hang from its connections (Fig. 3). These batteries provide power for pre-start
throttle location, and auxiliary ignition power. They are charged while the generator is running.
Inspect them periodically, or as part of a troubleshooting procedure.
Remove the batteries from their tray for inspection; their voltage should be 3.2-4.0V depending
on the temperature. If the voltage is ≤2.7V, replace both of the Li-ion batteries. If the Li-ion
batteries are not maintaining their charge during frequent generator usage, then check the
charging voltage between the red and black wires of the Li-ion battery connector (Fig. 3) while
the generator is running. The charging voltage can be checked with the batteries in, or out, of the
tray. It should be 3.7-4.2V. If the voltage is within this range but the batteries are not maintaining
their charge, replace the batteries. If the charging voltage is not in this range then test the voltage
regulator refer to (section 4.13).
Check the Li-ion batteries’ voltage and inspect the terminals monthly during long term storage. If
the voltage ≤2.7V or the terminals are corroded, replace the Li-ion batteries.This battery must be
replaced with the OEM replacement battery or the exact equivalent (this battery is typically listed
as 3.7V and 3400mAh by most retailers).
Fig. 3
Fig. 2
Li-ion Battery
Connector
Put the positive end of both
of the Li-ion batteries
towards the top of the tray.

16 PH3300i SM, Rev. 2017-01-20
3.3 Checking the Oil Level
Stop the engine and check the oil level, be sure to put the engine on a flat surface■when checking.
1. Loosen the screw on the engine oil access cover and remove the cover.
2. Remove the oil filler cap and check for the oil level.
3. If the oil level is low, add oil until it reaches the edge of the upper line on the dipstick (when
screwed in as shown in Fig. 4).
4. Re-install the dipstick and the engine oil access door before restarting your generator.
Upper Limit
Lower Limit
Upper level
Lower level
Fig. 4

17 PH3300i SM, Rev. 2017-01-20
3.4 Changing Oil
Make sure to turn the engine switch and fuel lever OFF before draining.
■
Drain the oil while the engine is still warm to assure rapid and complete draining.■
1. Loosen the screw on the engine oil access cover and remove the cover.
2. Remove the oil filler cap.
3. Install the oil drain pipe.
4. Drain dirty oil into a container. Allow enough time for the oil to drain completely.
5. Refill with the recommended oil, and check the oil level.
6. Reinstall the access cover and tighten the screw securely.
Engine oil capacity: 1.0L (35 oz.)
Please dispose of used motor oil in a manner that is compatible with the■environment and local disposal regulations. Do not throw oil in the trash or pour oil
on the ground.
Upper Limit
Lower Limit
Upper level
Lower level
Fig. 5

18 PH3300i SM, Rev. 2017-01-20
3.5 Air Filter Inspection and Cleaning
1. Loosen the panel screws and remove the side maintenance door.
2. Remove the two filter cartridge retaining screws.
3. Remove the filter cartridge and the filter element.
4. If filter element and the filter case are soaked with excessive engine oil this could be a sign of
excessive blow-by or a defective PCV valve. Pull the spark plug to check for signs of oil burning
or fouling (section 3.6). If the plug looks normal but the PCV hose is full of oil, replace the PCV
valve (must replace the whole valve cover).
5. Wash the filter element in a non-flammable or high flash point solvent and dry them thoroughly.
6. Soak the filter element in clean engine oil and squeeze out any excess oil.
7. Reinstall the filter element and the air filter cartridge. Tighten the two cartridge screws securely.
8. Reinstall the maintenance door and tighten the screws securely.
A dirty air filter will restrict air flow to the engine, reducing engine performance. If■the engine is operated in dusty areas, clean the air filter more often than specified
in the Maintenance Schedule (section 3.1).
Never run the engine if there is no filter element or if the filter is damaged, as it will■cause serious damage to the engine.
Air Filter Cartridge
Air Filter Element
Maintenance Door
Air Filter Case
Fig. 6

19 PH3300i SM, Rev. 2017-01-20
0.6 –0.7mm
NEW
WORN
NORMAL
Carbon–Too Rich
LEAN
FLOODED
Ash deposits -
Burning oil
Oil Fouled
Fig. 7
3.6 Spark Plug Inspection and Cleaning
1. Remove the spark plug using a plug wrench
and carefully inspect it. Compare the color and
deposits on the plug to Fig. 7. It should look
normal, or worn if it is time for replacement.
Evidence of lean, rich or flooded conditions
indicate there is a carburetor, choke, or fuel
delivery issue. Ash deposits are evidence of oil
burning under normal combustion conditions
and usually show up toward the end of the
engine’s service life; more frequent plug
replacement will be required. Oil fouling is
evidence of far too much oil entering the
cylinder, usually engine repair will be required
to fix the problem (sections 5.12, 5.13 & 5.14).
Oil burning can also be caused by a faulty
PCV valve (built into the valve cover). This will
cause large amounts of engine oil to get pulled
through the PCV hose, collect in the air
cleaner, and get sucked into the carburetor. If
this is the case, try replacing the PCV valve
(valve cover).
2. Remove carbon or other deposits with a plug cleaner or stiff wire brush. Check the sealing
washer for damage.
3. Measure the plug resistance; replace the spark
plug if the resistance is
outside of these values.
4. Measure the plug gap with a wire-type feeler gauge.Adjust by bending the side electrode if the
measurement is not within the specified tolerance.
5. Install the plug finger tight to seat the washer and then tighten with a plug wrench. Torque the
spark plug to 11-13Nm (8-10ft-lbs) or ⅛ of a turn after seating with a previously compressed
washer, or ¼ turn after seating with a new uncompressed washer.
Torque valve is 8.0-10 ft.-lbs. (11-13 Nm)
Spark Plug Type
F7RTC
Spark Plug Resistance
3 - 9 kΩ
Spark Plug Gap
0.6 - 0.7mm (0.024” - 0.028”)

20 PH3300i SM, Rev. 2017-01-20
Fig. 9
3.7 Valve Clearance Inspection and Adjustment
Valve clearance inspection and adjustment must be performed with the engine■cold.
1. Remove spark plug, valve cover bolt, valve cover and valve cover gasket.
2. Rotate the engine in a clockwise direction until the piston is at top dead center (TDC) and the
intake and exhaust valves are closed.
3. Insert a feeler gauge between the rocker arm and the valve and measure the valve clearance,
see Fig. 9.
4. If adjustment is necessary, proceed as follows:
a. Secure the rocker arm adjustment nut and loosen the jam nut.
b. Adjust the rocker arm nut until the desired valve clearance is attained.
c. Secure the rocker arm nut and tighten the jam nut. Recheck the clearance.
5. Clean the cylinder block and valve cover.
6. Replace the rubber valve cover seal.
7. Install the removed parts in the reverse order of removal.
Valve clearance
Intake
0.10 ± 0.02mm (0.004” ±0.001”)
Exhaust
0.15 ± 0.02mm (0.006” ±0.001”)
Valve Cover
Bolt
Valve Cover
Valve Cover Gasket
Spark Plug
Fig. 8