Parsun T25BM JET User manual

OUTBOARD MOTORS
OWNER’S MANUAL
T25BM JET
T30BM JET

SUZHOU PARSUN POWER MACHINE CO., LTD.
Before Operating Outboards
WARNING
：
Read this manual carefully. Learn the difference in handling characteristics between a
jet drive outboard motor and a propeller driven outboard motor. If you have any questions,
contact your dealer.
Unlike propeller driven outboard motor, steering at the low speeds, the jet drive
outboard motor tends to lose steering control as less water is drawn in and expelled.
Increase speed slightly to regain steering.
The jet drive is highly maneuverable at higher speeds, more so, than propeller driven
outboard motors. Use caution when turning to prevent spin - outs.
The impeller will continue to rotate while the engine is in neutral. Although the
approximate balancing of forward and reverse thrust will minimize outboard motor
movement, the outboard motor may tend to move slowly forward or backward. This is
normal for a direct - drive jet driven outboard motor. The operator should be aware of this
and use caution whenever the engine is running.
SUZHOU PARSUN POWER MACHINE CO., LTD

Table of contents
1. Main components and General information .................................................................................................. 1
1.1 Main components ......................................................................................................................................... 1
1.2 Specification.................................................................................................................................................. 2
2. Operation......................................................................................................................................................... 3
2.1 How the Jet Drive operates.......................................................................................................................... 3
2.2 Steering the boat........................................................................................................................................... 5
2.3 Mooring the Boat .......................................................................................................................................... 6
2.4 Cleaning the Impeller.................................................................................................................................... 7
2.5 Lubricating the Driveshaft Bearing............................................................................................................... 8
2.6 Operating In Freezing Temperatures........................................................................................................... 9
2.7 Pre-Starting Check List............................................................................................................................... 10
2.8 Operating In Salt Water or Polluted Water .................................................................................................11
2.9 Operating In Shallow Water ........................................................................................................................11
3. Maintenance.................................................................................................................................................. 12
3. 1 Impeller Removal and Installation............................................................................................................. 12
3.2 Worn/Dull Impeller ...................................................................................................................................... 14
3.3 Steering Pull Adjustment ............................................................................................................................ 15
3.4 Impeller Clearance Adjustment.................................................................................................................. 16
3.5 Replaceable Jet Drive Shear Key.............................................................................................................. 17
3.6 Shift Cable Adjustment ............................................................................................................................... 18
3.7 Corrosion Control Anode............................................................................................................................ 21
3.8 Lubricating the Driveshaft Bearing............................................................................................................. 22
4. Engine installation......................................................................................................................................... 24
4.1 Transom height of the boat ........................................................................................................................ 24

4.2 Locate center line of the outboard............................................................................................................. 24
4.3 Determining the Mounting Height of the Outboard ...................................................................................25
4.4 Water Testing .............................................................................................................................................. 27
5. Troubleshooting ............................................................................................................................................ 29

1
1. Main components and General information
1.1 Main components
1.Top cowling 8.Clamp bracket 15. Engine stop button
2.Top cowling lock handle
9. Tilt & trim rod
16.Clam bolt
3.Gear shift link lever 10.Water inlet 17.Water pump adapter
4.Shift cam plate 11.Starters handle 18.Intake seat
5.Reverse gate 12.Air choke handle 19.Fuel tank
6.Anode 13.Throttle grip
7.Steering handle
14.Gear shift handle

2
1.2 Specification
Main technical data:
Items
Data
Items
Data
Type of engine
Two cylinders,2-stroke
Spark plug
BPR7HS
Displacement
496cm3
Recommended fuel
Unleaded regular gasoline
Bore X stroke
72mm×61mm
Mixing ratio
50:1
Overall length
913mm
Fuel tank capacity
24L
Overall width
420mm
Recommended engine oil
2-stroke engine oil
Overall height
1025mm
Recommended transom height
381mm
Trim stages 4 Weight 63Kg
Gear reduction ration 1：1
Main performance:
Items Data Items Data
Maximum output 18.4Kw/5000rpm(25HP) Tightening
torque for
engine
Spark plug 18.0Nm
22 Kw/5500rpm(30HP)
Full throttle operating range 4500~5500rpm
Idling speed (in neutral) 1100±50rpm

3
2. Operation
2.1 How the Jet Drive operates
A jet driven outboard motor has substantially different handling characteristics compared to a propeller
driven outboard motor. It is recommended that the operator adjusts to these characteristics by
experimenting in open water at both high and low speeds. The driveshaft driven impeller draws water up
through the water intake and then redirects it at a high pressure through the water outlet nozzle to create
forward thrust. To obtain reverse, the reverse gate moves over the outlet nozzle to direct the water in the
opposite direction.
B
C
A
A-Water intake
B-Water outlet nozzle
C-Reverse gate

4
When the jet drive is in neutral, the impeller continues to rotate. However, the reverse gate is positioned so
that some of the forward thrust is diverted to create reverse thrust. This approximate balancing of forward
and reverse thrust will minimize any boat movement. Because the impeller is always rotating and creating
thrust when the engine is running, the boat may tend to move slowly forward or backward. This is normal
for a direct-drivejet driven boat. The operator should be aware of this and use caution whenever the engine
is running.
WARNING
：
Avoid injury resulting from contacting the rotating impeller or having hair, clothing, or loose objects
drawn into the water intake and wrapping around the impeller shaft. Stay away from the water intake and
never insert an object into the water intake or water outlet nozzle when the engine is running.
The jet drive is always drawing water into the housing when the engine is running. Do not operate
the jet drive with the grate removed from the water intake. Keep hands, feet, hair, loose clothing, life
jackets, etc., away from the water intake. Never insert an object into the water intake or water outlet
nozzle when the engine is running.
In an emergency, putting the jet outboard into reverse and applying reverse throttle can rapidlyslow
down the boat and reduce stopping distance. However, such a maneuver may cause occupants in the
boat to be thrown forward or possibly out of the boat.

5
2.2 Steering the boat
The jet drive is dependent on water jet thrust for steering the boat. If the water jet thrust should ever stop
(water blockage, engine stops, etc.), the boat will slow to a stop. However, while slowing there will be a
reduced ability to steer the boat.
WARNING
：
Steering the vessel in a tight turn can result in loss of boat control. In some cases, the boat can spin
out or roll over, causing serious injury or death. Avoid steering beyond the capabilities of the vessel,
especially at high speeds.
A loss or reduction in water jet thrust will directly affect boat directional control, and may result in
property damage, personal injury, or death. Boat directional control can also be substantially reduced or
lost altogether by a sudden loss of power such as running out of gas, quickly backing off the throttle,
turning off the ignition switch, activating the lanyard stop switch, or plugging the water intake to the jet
pump. Use caution when maneuvering at high speeds in areas where debris (weeds, logs, gravel, etc.)
could be picked up into the jet drive. The ability to take evasive action is dependent on sufficient water jet
thrust to control the boat.
While steering the boat at engine speeds above idle, the boat will respond quickly; but, due to the
relatively flat-bottom hulls and lack of a gear case in the water, the boat will tend to skid on turns. Turns
must be started early and use sufficient power to maintain steering control.

6
2.3 Mooring the Boat
Be sure to tilt the jet drive out of the water when the boat is pulled onto a beach or tied to a dock in shallow
water. Failure to do this may cause the water intake housing to fill with sand or debris and could prevent the
outboard from cranking over for starting.
WARNING
：
A rotating impeller could cause injury if contact is made with hands, clothing, or tools. To avoid injury,
keep hands and clothing away from the inlet or outlet of the jet drive, regardless of whether the boat is in
the water. Secure tools and loose items to avoid being struck by projectiles as a result of contact with the
rotating impeller, and to prevent damage to the impeller.
A large amount of debris being drawn into the water intake may result in a loss of power. Intake
suction holding debris against the grate will result in restricted water flow. Shutting the engine off may
allow the debris to fall off the intake grate allowing full power to be restored. If debris does not fall off the
intake grate, the engine must be shut off and debris physically removed from the grate.

7
2.4 Cleaning the Impeller
WARNING
：
Rotating the flywheel to free a lodged impeller can accidentally start the engine, resulting in serious
injury or death. Always remove the lanyard of emergency stop switch and remove all spark plugs.
It is possible for debristolodgebetween the impeller and jet housing wall, especially after the engine
has been stopped. This will lock the driveshaft and will prevent the engine from being able to crank over
for starting. Following are steps for dislodging the impeller.
1. Position lanyard stop switch to the “OFF” position.
2. Remove spark plug leads to prevent the engine from accidentally starting.
3. Remove flywheel or rewind cover and rotate the engine flywheel counterclockwise.
If this does not dislodge the impeller, it will be necessary to remove the six screws and water intake
housing.

8
2.5 Lubricating the Driveshaft Bearing
Before each use, lubricate the driveshaft bearing.
1 2
1. Remove lubricating oil hose from the grease fitting.
2. Pump in grease through the grease fitting, using the grease gun.
3. Reconnect the hose to the grease fitting when excess grease exits the hose.
CAUTION:
The lubricant recommended is a water resistant grease of the proper consistency for this application. If a
substitute is used, be sure that it is water resistant and of the same consistency.
Photos are for reference only

9
2.6 Operating In Freezing Temperatures
If there is a chance of ice forming on the water, the jet drive should be raised out of the water and drained
completely of water. If ice should form at the water level inside the outboard driveshaft housing, it will block
water flow to the engine causing possible damage. Do not start the engine until the ice is clear.

10
2.7 Pre-Starting Check List
• Operator knows safe navigation, boating, and operating procedures.
• An approved personal flotation device of suitable size for each person aboard and readily accessible (it is
the law).
• A ring type life buoy or buoyant cushion designed to be thrown to a person in the water.
• Know your boats maximum load capacity. Look at the boat capacity plate.
• Fuel supply OK.
• Ensure the boat drain plug is installed.
• Arrange passengers and load in the boat so the weight is distributed evenly and everyone is seated in a
proper seat.
• Tell someone where you are going and when you expect to return.
Know the waters and area you will be boating; tides, currents, sand bars, rocks, and other hazards.
• Check steering for free operation.
• Check for debris around the rudder and reverse gate which may jam or hinder operation.
• Before launching, examine the jet drive water intake for obstructions which may prevent pumping of water.
• Ensure the driveshaft bearing on the jet drive is lubricated.

11
2.8 Operating In Salt Water or Polluted Water
If the boat is kept moored in the water, always tilt the outboard so the water intake is completely out of water
when not in use.
Wash down the outboard exterior and flush out the exhaust outlet of the jet drive with fresh water after each
use.
When used in salt water more than in fresh water, remove mounting hardware, grease, and reassemble
once a year. Failure to do this may result in hardware that is difficult if not impossible to remove at a later
date.
2.9 Operating In Shallow Water
The life of the impeller and water intake can be greatly increased by avoiding the intake of sand and gravel.
The intake suctionwill actlike a dredge when thewaterintake comes close to the bottom. It is better to stop
the engine and drift up to shore when landing, and to shove off with an oar when leaving. The engine can
idle through areas of water less than 61 cm (2 ft.) deep, but there should be more than 61 cm (2 ft.) of water
under the boat when increasing speed to reach full plane.
Once the boat is on plane, the boat speed will prevent the ingestion of gravel and other debris from the
bottom. The suction is still present, but the water intake passes too quickly over the bottom to allow debris
to be drawn into the water intake.
When boating through shallow water areas, choose a course of travel that avoids sharp rocks and other
underwater obstacles that could damage the boat. Running the boat through these areas on full plane may
be helpful as the boat will be riding higher in the water. If the boat gets stuck on the bottom, immediately
stop the engine and move the boat to deeper water.

12
3. Maintenance
3. 1 Impeller Removal and Installation
WARNING
：
Rotating the driveshaft may cause the engine to crank over and start. To prevent this type of accidental
engine starting and possible serious injury caused from being struck by a rotating impeller, always turn the
ignition key or lanyard stop switch to the “OFF” position and remove the spark plug leads from the spark
plugs while servicing the impeller.
1. Position the key switch or lanyard stop switch to the “OFF” position.
2. Remove the spark plug leads to prevent the engine from starting.

13
3. Remove the six nuts securing the water intake housing, and remove the water intake housing.
4. Straighten the bent tabs on the impeller nut retainer and remove the impeller nut.
b a
a - Tabs b - Impeller nut
5. Pull the impeller straight off the shaft.
If the impeller is tight, use a hammer and a block of wood to rotate the impeller clockwise on the shaft until
the keyway is directly above the flat on the shaft. This will free the jammed key and allow removal.

14
3.2 Worn/Dull Impeller
The intake of gravel through the pump can round off and wear the leading edges of the impeller. Some
conditions that could be experienced from a worn/dull impeller are as follows:
• Noticeable performance loss, especially on acceleration
• Difficulty getting the boat on plane
• An increase in engine RPM at wide open throttle
CAUTION:
Do not sharpen or alter the top side lifting angle. Check the impeller blades occasionally for damage. Use a
flat file to re sharpen the leading edges. Sharpen to a 0.8 mm (1/32 in.) radius by removing material from
bottom side only.
b
a
a - Leading edge
b - Top side lifting angle

15
3.3 Steering Pull Adjustment
The steering on some boats will have the tendency to pull towards starboard. This pulling condition can be
corrected by using a pliers and bending the ends of the exhaust fins 1/16 in. (1.5mm) toward the starboard
side of the outboard.
a
a - Exhaust fin

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3.4 Impeller Clearance Adjustment
The impeller should be adjusted so there is approximately 0.8 mm (0.031 in.) clearance between the
impeller edge and liner. Operating the jetdrive in waters that contain sand and gravel cancause wear to the
impeller blades, and the clearance will start to exceed 0.8 mm (0.031 in.).
As the blades wear, shims located in the stack outside of the impeller can be transferred behind the impeller.
This will move the impeller further down into the tapered liner to reduce the clearance.
a
b
a - Shims
b - Clearance between impeller edge and liner
Check the impeller clearance by sliding a feeler gauge through the intake grate and measure the clearance
between the impeller edge and liner. If adjustment is required, refer to 3.1 Impeller Removal and
Installation.