In the world of boating technology, Igor Gusar is well known to those who appreciate a deep technical approach to the maintenance of outboard motors (outboard motor), whose diagnostic technique is based not on fortune-telling by symptoms, but on a clear understanding of the physical processes occurring inside. two-stroke or four-stroke engineOwners of equipment often face situations where the engine loses traction or makes extraneous sounds, and it is system analysis that avoids expensive overhauls.
Experience shows that most breakdowns could be prevented with timely maintenance. carburetor And the ignition system requires attention long before the engine fails at the most inopportune moment on the water. Ignoring primary signs of malfunction, such as unstable speeds or difficulty starting, often leads to a piston burn or failure. electronic control unit.
In this article, we will explore the key aspects of restoring engine performance, based on proven solutions, you will learn how to correctly interpret the color of candles, why lower unit knocks and when a complete bulkhead is necessary. crankshaftUnderstanding these nuances will allow you to self-correct up to 70% of common problems.
Diagnostics of the engine by external signs and sound
Primary diagnostics begin long before the engine is disassembled, an experienced technician can determine the nature of the malfunction by the sound of the engine running and visual signs. Igor Gusar recommends that you first pay attention to the nature of the exhaust and the color of the smoke. If thick gray smoke is pouring out of the silencer, this is a sure sign that excessive amounts of gas are entering the combustion chamber. oils, which may indicate wear of the oil oil glands or improper adjustment of the oil pump.
Knocking at the bottom of the motor is often confused with knocking, but the nature of these sounds is different. crank-and-shifterWhile a thunderous roar may indicate the destruction of lower unit bearings, it is important not to ignore these signals, as continuing to operate the motor with damaged bearings will lead to jamming of the shaft and costly repairs.
Excessive vibration at idle speeds often indicates dissynchronization of cylinders or problems with the cylinders. ignitionIf the vibration only appears under load, the propeller group may be damaged or the lower unit may be deformed, and precisely localizing the source of the vibration reduces the time needed to find a fault.
Audit and setting up of the ignition system
The ignition system is the heart of any gasoline engine, and errors in its operation are critical to the stability of the engine. hall-sensor The wrong gap leads to a weak spark, especially at high revs, which causes ignition misses and power drops.
Diagnostics often reveal oxidation of contacts in high-voltage wires or on candles themselves. In the high humidity conditions characteristic of the operation of outboard motors, this becomes the main cause of failure. dielectricwhich displace moisture and prevent corrosion.
The switch is also an important element, and overheating often causes the engine to suddenly stop after a long period of full-gas operation. If the engine stops and does not start until it completely cools, there is a 90% chance that the heat breaks down the components. CDI module In such cases, the unit needs to be replaced or professionally repaired.
Maintenance and repair of carburetor system
The carburetor is the most sensitive fuel quality unit. Igor Gusar notes that the use of expired or water-impurified gasoline is guaranteed to lead to resinous deposits in the chiclera. This disrupts the proportions of the fuel-air mixture, making the engine unstable. Regular ultrasound washing of the carburetor is a mandatory procedure for engines running on ethanol-containing fuels.
The quality of the mixture is adjusted not only by the color of the soak on the candles, but also by the behavior of the motor when the throttle is sharply opened. If the engine "chokes" with a sharp addition of gas, the mixture is too poor. If there is black smoke and loss of reception, the mixture is overenriched. The precise adjustment of the screws of quality and quantity requires the use of tachometer for speed control.
☑️ Fuel system check-up
The fuel pump, which is common in two-stroke engines, often ruptures the membrane or sticks the valves, and causes the engine to run on only float chamber fuel and to stall as soon as it runs out without having to pump a new tank portion. Replacing the pump remix is a simple operation that you can do yourself.
Defection and bulkheading of lower unit
The bottom of the motor, or lower unit, takes all the blows of the water element. Inside it are gears of the gearbox that work in an oil bath. Igor Gusar recommends changing the oil in the gearbox every 50-100 hours or once a season. The presence of an emulsion (white) in the oil being drained indicates that water enters the glands, which requires immediate replacement of the seals.
The front and rear gears are subject to wear, especially if the gear shifts were made at high speeds. The appearance of backlashes or metal shavings in the oil indicates the need for defects in the assembly. bearing and glands, as their destruction can lead to jamming of the paddle shaft and loss of control of the boat.
| Component | Symptom of malfunction | Elimination method | Frequency of verification |
|---|---|---|---|
| The ointment of the paddle shaft | Oil film on water, emulsion in the gearbox | Replacement of oil, polishing of the shaft | Every season. |
| Shaft bearings | Hooding, backlash, heating | Bearing replacement | When noise is made |
| Reverse gears | Knocking the gear, grinding | Defective and replacement of a pair of gears | With symptoms |
| Stoke sealing | Air suction, loss of traction | Replacement of sealing rings | Once in season 2 |
The vibration of the motor can weaken the joints, which will lead to depressurization of the body. The use of original gaskets and sealants that are resistant to sea water is a prerequisite for the durability of repairs.
Problems of the cooling system and overheating
Overheating of the engine is one of the most dangerous malfunctions that can destroy the engine in minutes. The main cause is often damage to the impeller of the water pump. The rubber of the impeller bluffs and cracks over time, especially if the engine has been idle for a long time without water. Igor Gusar advises changing the impeller prophylactically every two years, without waiting for a complete failure.
Clogging cooling channels with algae, sand or salt deposits also reduces the efficiency of the heat sink. In salt water, the corrosion of the internal channels is faster, so flushing the system with fresh water after each foray into the sea prolongs the life of the motor. Using the thermostat also requires attention: jamming the valve in the closed position will lead to rapid boiling.
⚠️ Warning: Never try to cool an overheated motor by watering it or dropping it into a body of water. A sharp temperature drop will cause a thermal shock of the metal, which will lead to cracks in the cylinder head or skewed pistons.
Temperature sensors and overheating alarms must always be in good working order. If the motor is equipped with a system of speed limiter during overheating, ignoring this mode of operation will lead to serious damage.
Fuel mixture and quality of fuels
For two-stroke engines, the quality of the gasoline-oil mixture is a critical parameter. Igor Gusar stresses that the use of oils is standard. TC-W3 The mixing ratio must be strictly in line with the manufacturer's guidelines, usually 1:25 for break-in and 1:50 for operation, but older engines may require a more oil-rich mixture.
Gasoline must be fresh. In long-term storage (more than 3 months), gasoline loses its properties, light fractions evaporate, and the remaining liquid forms a resinous sludge. If you cann the engine for the winter, be sure to produce fuel from the carburetor or use fuel stabilizers. Starting the engine on an old mixture can lead to coking rings and channels.
Fuel filtration is another important step, and even new gasoline can contain mechanical impurities, and installing additional sediment filters in front of the carburetor allows you to capture the water and dirt that protects the jellyfish from clogging, a simple upgrade that greatly improves the reliability of the power system.
Conservation and storage of the motor
Properly conserving the engine for the winter period allows you to extend its life for years. Igor Gusar recommends a comprehensive approach: draining fuel, treating the internal cavities with oil, lubricating all hinges and protecting against moisture. The motor should be stored in an upright position so that water does not enter the cylinders through the exhaust hole.
The appearance of the motor also requires protection. Aggressive environment, solar ultraviolet and temperature changes destroy paint and plastic. The use of protective covers and regular washing with autochemistry for outboard motors help to maintain a presentable appearance and prevent corrosion of aluminum alloys.
⚠️ Attention: When storing the motor in an unheated room, make sure there is no water left in the lower unit. Frozen water will expand and can rupture the pump or gearbox body, leading to costly repairs in the spring.
Before the first start after wintering, you need to remove the candles, pour some oil into the cylinders and turn the crankshaft with a starter several times, which will create an oil film on the cylinder mirror and prevent dry friction at start-up, only after this procedure you can install candles and start the engine.
Frequently Asked Questions (FAQ)
Why does the engine stop at high speeds?
This is most often a sign of fuel problems (a jet lag, a faulty fuel pump) or a heat breakdown in the switch, and it may also be caused by air suction through the crankshaft coils.
How often should you change the oil in the gearbox?
It is recommended to change the oil in the lower unit gearbox once a season or every 100 motor hours, and if an emulsion appears in the oil, you need to make a replacement immediately and find the cause of the water entering.
Can I use car oil for two-stroke engines?
Absolutely not. Automotive oils don't burn completely at low two-stroke temperatures, which causes soaking, rings, and engine failure. Use only TC-W3 oils.
What to do if water gets into Daydwood?
You need to immediately stop operation, drain emulsified oil, wash the gearbox with a special washing oil or diesel, replace the oils and bearings, and then pour fresh transmission oil.