Choosing the first or additional engine for a small boat is always about finding a balance between price, reliability and weight. Kamu 5 hp. (often labelled as Kamu Or, as an OEM analogue of Tohatsu/Mercury, it occupies a special niche of affordable and time-tested solutions. two-stroke It has become a popular choice among fishermen and small inflatable boat owners due to its simplicity of design and maintainability.
In this article, we'll go into detail about what this unit is, how it behaves in real life, and what to expect from its operation. It's important to understand that, despite the appearance of similarities with more famous brands, it's not a problem. build-quality The materials used can vary depending on the batch and the component supplier, but the basic engineering platform on which it is built has proven itself for decades.
We will look at the technical nuances, the features of the carburetor settings and the typical problems faced by owners. Kamu's 5 hp. It's a working tool that, if properly maintained, can last for years, but it requires attention and understanding of how two-stroke circuits work.
Technical specifications and design features
Basis Kamu 5 It's a classic two-stroke, crank-chamber blowing circuit, and it has a single cylinder with a displacement of about 100 cubic centimeters, which is standard for a 5-horsepower class. Power The shaft is achieved by high revs, which is typical for such engines. The unit weighs in the area of 20-21 kilograms, which allows you to transport it in the trunk of a passenger car, although it can not be called ultra-light.
The cooling system is water-based, forced, and the water is sucked through the intake in the lower unit and circulated around the cylinder block and the exhaust pipe. Thermostat In this modification, it is often absent or made in the form of a simple valve, so it is important to monitor the control stream ("urinal") to make sure that there is circulation.
When running a new engine, be sure to check the presence of a control jet every 10-15 minutes of operation, even if the engine is running at idle speeds.
The fuel system includes a built-in 1.2-liter fuel tank and an external 12-liter tank (optional). The carburetor is membrane-type, which allows the engine to operate under any slope, although prolonged upside down work is not recommended due to the peculiarities of lubrication. Ignition system Electronic (CDI) that does not require adjustment of the gap, which reduces the number of service points.
- 🚤 Engine type: two-stroke, single-cylinder
- ⚖️ Weight: 21 kg (with screw, no fuel)
- ⛽ Tank volume: 1.2 L (built-in) + external 12 L
- 🔄 Cooling: water-force
⚠️ Warning: Do not start the motor out of the water (on land) even for a few seconds. The absence of a water jacket will instantly overheat and jam the piston group.
Dynamics, fuel consumption and productivity
Real power. Kamu 5 hp. It allows you to confidently glid light inflatable boats up to 3 meters long with one person on board. For heavier hulls or if there is a second passenger, the engine will operate in displacement mode, providing a speed of about 6-8 km / h. This is not a racing projectile, but a thrust-hard worker for quiet movement.
Fuel consumption is one of the main parameters for economical water-engines: in full gas mode, a two-stroke consumes about 2.5-3 liters of gasoline mixture per hour. When driving in economical mode (about 3000-3500 rpm), the flow rate is reduced to 1.5-1.8 liters. Economy It depends on the quality of preparation of the mixture and the condition of the carburetor.
It's important to note that to achieve the stated performance, you need to choose the right screw. The standard screw has a step that is focused on universal use. If the engine "does not roar" or, conversely, "roars" without a set of speed, you need to replace the screw with a higher or lower speed, respectively. Selection of screws This is the key to unlocking the engine’s potential.
| Mode of work | Turnover (rpm) | Fuel consumption (L/h) | Speed (km/h)* |
|---|---|---|---|
| Idle move | 1000 - 1500 | 0.4 - 0.6 | 3 - 4 |
| Economical | 3000 - 3500 | 1.5 - 1.8 | 12 - 15 |
| Full gas. | 5000 - 5500 | 2.5 - 3.0 | 20 - 25 |
* Speed is indicated for a PVC inflatable boat with a length of 3.2 meters with one operator (weight ~ 80 kg).
Fuel mixture and preparation for launch
Since Kamu 5 It is a two-stroke engine, it has no oil lubrication system in the crankcase, the lubrication is carried out by oil added directly to gasoline. The mixing ratio is critical: usually 1:50 (20 ml of oil per 1 liter of gasoline) for break-in engines and 1:25 (40 ml per 1 liter) for new or when working in heavy conditions. Oil quality It must comply with the TC-W3 standard.
Use a separate canister to prepare the mixture, rather than pouring the components directly into the engine tank, which will ensure that the oil is evenly distributed and prevent the mixture from stratifying. Shake the canister before each refueling, as gasoline and oil have different densities and can be delaminated during prolonged standing. break-in The new engine requires a richer mixture (more oil) in the first tanks.
☑️ Preparation of the fuel mixture
Before starting, you have to do several things: check the fuel level, make sure the fuel crane is open (if there is an external tank), and pump the system with a pear-primer to elasticity. The gas handle on the tiller is translated into the "Start" position. Only then you can pull the starter. Launching system Kamu 5 is simple, but requires a sharp and confident jerk.
⚠️ Warning: Never use pure gasoline without oil. Even short-term work on clean gasoline will lead to cylinder bullying and overhaul.
Maintenance and maintenance
Regular maintenance - the guarantee of longevity Kamu 5The main focus should be on the spark plug, and its condition will tell you about the quality of the mixture: brown soda is normal, black is over-enriched, white is overheated or poor mixture, you need to clean the candle with a soft brush without damaging the electrode. Candle gap shall be between 0.7 and 0.8 mm.
Water pumps also require monitoring, and once a season or every 100 hours, it is recommended to remove the bottom cover of the lower unit and check the condition of the impeller. Rubber blisters and cracks over time, which leads to a loss of pump performance. The lubricant changes annually, before winter preservation. Transmission oil should be transparent; if it is milky color, then the sealing of the ossuaries is broken and water is hit.
How to properly preserve the engine for the winter?
Pour the residue of fuel out of the carburetor, twist the candle and pour 5-10 ml of engine oil into the cylinder. Make a few turns with the starter so that the oil spreads out across the walls. This will prevent corrosion during downtime.
The appearance of the motor is important, too. KamaThey're susceptible to galvanic corrosion in salt water, and after every sea trip, you have to wash the motor with fresh water, and you have to pay special attention to the places where the paint chips are, and you have to paint them with anticores right away. Anodic protection (zinc plates) on lower unit should be intact and not covered with oxides.
Typical malfunctions and methods of their elimination
Like any technique, Kamu 5 hp. It can be a problem, and one of the things that's common is that you have a hard time starting after a long time of downtime, and often it's because the crankshaft or the carburetor cuff is leaky, the gasoline is going away, and the float chamber is not getting fuel, and the solution is to replace the remix of the gaskets and the oils. Tightness The fuel system is a priority.
Another common problem is power loss and overheating. If the engine is not pulling and the control jet is weaker, the cooling system channels are likely clogged or the water pump impeller is damaged, and it is also worth checking the exhaust windows for the presence of coarse material that narrows their section. Cleaning The cooling system often returns the engine to factory performance.
- 🔧 Problem: The engine is dead on the blanks.
Decision: Adjustment of the quality screw of the mixture or cleaning of idle jeeler. - 🔧 Problem: Vibration at high speed.
Decision: Checking the screw balance and no damage to the blades. - 🔧 Problem: Oil leaking out of the gearbox.
Decision: Replacement of the drive shaft or sealing rings.
If the motor is making a foreign knock, immediately turn it off. This may indicate a failure of the rod bearing. Operating with a damaged bearing will lead to the destruction of the rod and crankshaft. Diagnostics by hearing an experienced motorist often allows you to determine the nature of the malfunction without a complete disassembly.
90 percent of the problems with starting two-stroke engines are related to the quality of the fuel mixture or the state of the spark plug.
Comparison with competitors and final conclusions
In its price segment Kamu 5 It competes with brands such as Parsun, Hidea and Tohatsu The main advantage of Kamu is its affordable price and simplicity of construction, which is devoid of complex electronics, and unlike more expensive ones, there are fewer plastic elements in lower unit, which increases resistance to impacts on rocks or sand.
However, the quality of casting and fitting parts Kamu It's a little bit more vibrating than the Japanese, and it's a little bit less resourceful before the first overhaul, but for seasonal use (30-50 hours a year), it's a great investment. Repairability It allows you to restore it on your own using publicly available spare parts.
In summary, it can be said that Kamu outboard motor 5 hp It's a reliable "working" option for those who value simplicity and low cost of ownership, and it won't surprise you with speed records, but it will surely get you to the cool spot and back, and if maintained properly, this two-stroke will be a loyal water assistant for many seasons.
Can this motor be used in salt water?
Yes, you can, but with a mandatory fresh water wash after each fishing, the aluminum alloys of the case are subject to corrosion, so you need to monitor the state of the anodic protection and the integrity of the paint coating.
Which gasoline is better to pour: AI-92 or AI-95?
For two-stroke engines like Kamu 5, the best choice is AI-92 gasoline. Higher-octane AI-95 has a higher content of alcohols and additives, which can negatively affect the rubber seals of the carburetor and evaporate faster, disrupting the mixture.
Should the engine be cooled before stopping?
After active operation at full speed, allow the engine to work for 2-3 minutes on idles, this will allow to level the temperature of the parts and avoid local overheating (heat shock) of the cylinder head after the water circulation stops.