Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Agnes - EX Module 1
Transcript of Agnes - EX Module 1
Engine Specification System
OHC vs. OHV
High Power & Torque
Advanced Combustion Chamber
The design of the combustion chamber on EX engines along with the positioning of the valve train helps with increased volumetric efficiency and more power out of the engine.
Aware of unique features & benefits
Competent in basic maintenance
Repairs over $100/$200
What is Covered?
What is Excluded?
Submit warranty claims directly to Subaru Power via the online warranty website
$100 for single cylinder engines
$200 for twin cylinder engines
Any work that involves internal engine parts will need pre-approval
Covers defects in material and workmanship
Fuel system problems caused by failure to use fresh fuel
Failure to properly prepare the machine prior to any period of non-use over a month
Contaminants in the fuel system
Lack of lubrication
Failure due to dirt entering the engine
Identifies the model and the configuration
11 digits, 5 for the model and 6 for the spec
The spec number is on the Product Label
Label located on the side of the blower housing
Optimized Combustion Chamber
Pent Roof Combustion Chamber
Intake & Exhaust Valves positioned for optimum performance
Electronic Low Oil Shut-Off
Periodic Maintenance Schedule Table
* Initial oil change should be performed after first twenty (20) hours of operation. Thereafter change oil every hundred (100) hours. Before changing oil, check for a suitable way to dispose of old oil. Do not pour it down into sewage drains, onto garden soil or into open streams. Your local zoning or environmental regulations will give you more detailed instructions on proper disposal.
With internal magnets for charging systems
Standard non-rotating recoil assembly
Special rotating screen and recoil assembly
15 watt charging system
200 watt regulator rectifier
200 watt (16 amp) stator & flywheel magnet ring
Optional Washable Air Filters
•Fits most popular models
•EX13, EX17, EX21, EX27 with top mount 2 stage air cleaner
•Wash in soap & water, rinse, drip dry and spray with light oil
Governor Internal Components
• Check oil with dip stick not screwed in
• Use 4-stroke automotive detergent oil of API service class SE or higher
• Oil change interval: after 20 hours initially, then every 100 hours
Fuel Tank Capacity:
Engines shipped from our factory are without oil.
Before starting the engine, fill with oil. Do not overfill.
Flywheel Magneto Ignition
Fuel Tank Cap
Fuel Tank Filter -
Bottom of tank
Fuel Shut Off Valve
Carburetor Drain Screw
Stop Switch in Ignition
Governor lever on the outside of the engine
Internal flyweights and governor gear
Urethane Foam Element Type
Paper Element Cleaning
• Governor rod and rod spring
• Governor lever
• Governor shaft
Muffler with cover and deflector
Wash in mild detergent
Squeeze the element
The foam element should be then lightly oiled with clean oil.
Squeeze out excess oil
Subaru EX manual maintenance recommends cleaning the foam element at least every 50 hours.
• Clean the elements in the same way as Dual Element Type (Urethane Foam and nonwoven Cloth elements)
Clean by tapping gently to remove dirt and blow off dust
Initial oil change: after 20 hours of operation
Thereafter: every 100 hours of operation
Always use the best grade oil. Contaminated oil, poor quality oil, and shortage of oil can cause damage to the engine or shorten the engine life.
To change the oil, stop the engine and loosen the drain plug.
Re-install the drain plug before refilling oil.
Drain the used oil while the engine is warm.
Warm oil drains quickly and completely.
Inspect spark plug electrode condition
Recommended Spark Plug-BR-6HS (NGK)
How to diagnose and treat common small engine problems
Flywheel Fan View
Main Bearing View
This is an introduction module to Subaru EX engines.
It will give you basic overview of the design and various configurations of the single cylinder EX engines.
EX engines single cylinder overhead cam range from 126 to 404 cc's and 4.3 to 14 horsepower.
This is an example of the engine label from EX21 engine.
We call the first 11 digits the spec number.
The remaining four numbers relate to the date of manufacture of the engine.
Engine serial number is unique for each engine model.
There is only one EX21 that has a serial number of 2484545, but there can also be an EX 27 with the same serial number.
These are the major components of a traditional overhead valve pushrod engine.
This is the Subaru EX chain drive overhead cam overhead valve engine.
2 Rocker Arm
1 Cam Gear
2 Push Rods
2 Rocker Arms
1 Valve Cap
This video is viewed from flywheel fan side of the engine showing valve operation.
This video is viewed from the main bearing side of the engine showing the chain which helps lubricate the top end of the engine.
EX engines use a case hardened steel timing chain which is designed to last the life of the engine.
The EX engines use the compression release built in the overhead cam which contributes to the easy starting of these engines.
All EX engines come standard with a recoil start system. The majority of the engines have recoils made of highly impact resistant resin material.
Some EX engines have rotating screens added under the recoil to cut down on intake of debris such as grass.
Most electric start engines have charging systems to recharge the battery. Charging systems are also offered for some specials non electric start engines, such as engines used for hot water pressure washers.
These are 15 and 40 Watt charging system rectifiers. Remember, 15 Watt is approximately 1.2 amps and 40 Watt is approximately 3 amps of charging at 12 volts.
This is the charge coil located under the flywheel coil for a 15 Watt-1.2 amp charging system.
Shown here is a 200 Watt- 16 amp regulator rectifier. This is considered a high output charging system component.
This is the stator and flywheel magnet ring for the 200Watt-16 amp charging system.
The flywheel on the left has the permanent magnets inside the flywheel. It also has a ring gear for an electric starter.
The flywheel on the upper right shows the magnets and stator for the charging system, but does not have the ring gear. This flywheel will be used for a special engine that has a 200 Watt charging system but is recoil start only.
***Note: a replacement ring gear is not available for EX flywheel. If you need a ring gear replaced, you would need to purchase a complete flywheel assembly.
Shown here is the chart that can be found in the EX Owner's Manual. It's important to follow the maintenance schedule to insure long engine life.
Subaru EX engines use different types of air cleaners. The foam type air cleaner element is intended for relatively clear applications where dirt is not commonly found. Example would be pressure washer.
The dual element foam over paper air cleaner element is more commonly used and will provide the engine with good filtration in many different applications.
Many EX engines are equipped with the low oil shut down.
The low oil shut down is located under the flywheel fan.
This eliminated the need to remove the engine from most equipment such as a pump or generator to service the low sensor float unit.
The EX engine has designed features that give it superior lubrication to the critical engine components.
EX engines come standard with two large oil drains.
EX engines use steel, corrosion resistant fuel tanks that vary in size depending the size of the engine.
Most new EX engines include a special fuel cap that controls evaporative emissions.
The fuel cap also has a retaining ring to keep it attached to the tank as mandated by federal emission laws.
All EX engines with fuel tanks have a large filter screen on the top of the tank.
EX13, EX17, EX21, EX7 engines have an additional fuel tank filter on the bottom of the tank as part of the fuel union-outlet.
This filtering union assembly should be checked if clean and replaced as needed.
All EX engines with fuel tanks are also equipped with fuel shut off valve.
This valve should be closed whenever the engine is not in use.
It's especially helpful when the engine is being transported.
Subaru EX engines have a carburetor drain screw on them that should be used when the engine is going to be stored for an extend period of time.
The fuel shut off also has a sediment bowl on the bottom that can be removed, cleaned and serviced.
The EX engines have cooling directed under the bottom of the crankcase, through the cylinder head and around the valves as well as cooling fins inside the crankcase to help keep the engine running cool during hot weather.
The flywheel fan has a permanent magnet mounted to the outside of the fan. This magnet helps produce the low voltage needed for the primary circuit of the ignition system.
The ignition coil converts the low voltage of the ignition primary into the high voltage needed to fire the spark plug.
Shown here is a newer style on-off switch. This switch serves multiple functions. It is used to stop the engine by grounding the ignition primary circuit. The switch also contains the controls for shutting the engine off when the oil float in the crankcase senses low oil.
The spark plug is a simple but important part of the ignition system. Spark plug must be the correct one for the engine.
Spark plugs vary by thread length, thread size as well as heat range.
All Subaru EX engines come standard with a flyweight type governor system.
The governor allows the engine to maintain a constant speed under varying loads.
The governor also keeps the engine running at safe speeds.
The major components are:
internal flyweights and governor gear which are driven by the gear crankshaft
an internal governor lever which is actuated by the spool of the governor flyweight assembly
an external governor lever which pens and closes the carburetor throttle depending upon the speed and load that the engine is operating under
governor spring which is used to help maintain the engine speed under varying loads
The governor is not normally required adjustment unless parts have been replaced or disassembled. The procedure for adjusting the governor is as follows:
Turn the speed control lever to the full speed position, making sure that the carburetor throttle valve is fully open.
Loosen the governor lever clamp at the governor shaft.
Hold the top of the governor shaft with the pliers and turn it clockwise as far as it will go. Tighten the bolt on the governor lever clamp.
Most EX engines come standard with a muffler. Some engine configurations come with an exhaust deflector while other use a small over the exhaust outlet.
The spark arrestor inside the muffler can be removed for cleaning with a fine wire brush.
In the next section, we will cover some basic engine service and maintenance.
Air cleaner element service varies depending on the design of the element.
The common EX air filter element is a washable foam over a non washable paper filter.
The foam single element as well as the foam outer wrap on the dual element filter should be washed in warm water and mild detergent. The foam should then be squeezed to remove the water and dried.
The same type of oil that is used for the engine crankcase will work fine for the foam element.
The paper element should be checked every 50 hours and even more often in extremely dusty conditions. Paper element can be tapped gently to remove dirt and blow off dust.
Some EX engines use an additional pre-cleaner that helps extend the life of the paper and foam dual element. The service interval for the pre-cleaner is dependent on the operating conditions of the engine.
Engine oil must be of the correct weight-SAE 5W-30, 10W-30, or straight 30 depending upon the ambient temperatures. Also, oil must be of the correct API class-SE or higher. Most automotive engine oils will exceed API class- SE. Do not use diesel engine oil unless it specifically includes API rating of-SE or higher. Diesel engine oil uses a rating system such as CD, CE, etc.
It is important to use the correct spark plug in the engine to prevent internal damage and also poor engine operation.
The next slides will show how you can determine the operating condition of the engine based on the condition of the spark plug.
Easy to pull
Advanced mechanical compression release system
OHC design advantage
** As to the procedures for these items, please refer to the SERVICE MANUAL.
Clean the paper element every 50 hours
Replace element set every 200 hours
NEVER use oil
Wash the dust cup of pre-cleaner in water
Install after drying
Spark plugs should be inspected as part of a routine maintenance and can be serviced.
Clean off carbon deposits on the spark plug electrode using a plug cleaner or wire brush.
Check electrode gap. The gap should be 0.6 mm to 0.7 mm (0.025 inch-0.030 inch)
Adjust the gap, if necessary, by carefully bending the side electrode.