Many owners of water-motor equipment, first encountering the term "automix" in the instructions for a new outboard motor, are wondering about the need for this function. Automatic mixing The goal of the oil and gasoline system is to make life easier for the driver by eliminating the need to carefully measure the proportions of the fuel mixture before each refueling, not just a marketing ploy, but an engineering solution that makes it much easier to operate two-stroke engines.
The essence of the technology is that the motor itself doses the oil depending on the current load and the speed of the crankshaft, so you no longer have to shake the canister, trying to evenly distribute the lubricant, or worry that you accidentally poured too little oil, which threatens to bully the piston group. Automix system takes these risks by providing stable lubrication of rubbing parts in any modes of operation.
But like any technical system, it requires an understanding of how to operate and maintain it properly. In this article, we will go into detail about how the oil is delivered, why it is important to use the right components, and how to avoid typical operating errors. Understanding these processes will prolong your motor life and ensure a smooth navigation.
The principle of operation of the automatic mixing system
On the basis mixer There's a separate oil pump that's mechanically or electronically connected to the throttle or the gas cable. When you open the throttle, increasing the engine speed, the pump automatically starts to feed more oil into the mixing chamber or directly into the intake manifold, which provides the perfect real-time ratio of the fuel-air mixture and lubricant.
Unlike the traditional method, where you prepare the mixture in the tank in advance, gasoline and oil are stored separately. Gasoline enters the carburetor or fuel ramp in the standard way, and the oil is supplied by a metering pump. Mixing proportions They can range from 1:100 at idling to 1:25-1:40 at full speed, which is the optimal mode to protect the engine from overheating and wear.
⚠️ Warning: Never fill a gas tank with a finished mixture of gasoline and oil if your engine is equipped with an automix system, which will lead to smoke, candles and potential failure of the catalyst or silencer.
Modern electronic engine control systems (ECUs) can even more accurately control this process by reading data from temperature and throttle position sensors. Yamaha, Suzuki and Tohatsu They're able to adapt to fuel quality and operating conditions, making the engine run smoother and more economical.
Advantages of Using Automatic Oil Feed
Transition to use carmix It gives the owner of the boat a number of undeniable advantages, the main of which is convenience: you do not need to carry measuring tanks, calculator to calculate the proportions or be afraid to confuse the canisters, just pour pure gasoline in one tank and special oil for 2T engines in another, smaller tank.
In addition, the automatic system provides more stable lubrication of the engine in transition modes. When manually mixed, the oil can precipitate or be distributed unevenly, especially if the mixture has been standing for a long time. Metering pump It supplies fresh oil directly at the time of need, which is critical for the life of the piston group and crankshaft bearings.
- 🛢️ Oil saving: The system delivers just as much lubrication as is needed at the moment, excluding overspending.
- 🔥 Reduced risk of overheating: When a throttle is opened sharply, the oil supply increases instantly, protecting the parts.
- 🧹 Exhaust purity: Optimal combustion of the mixture reduces the amount of soak on candles and piston rings.
- ⏱️ Refueling speed: The process of refueling takes a minimum of time on shore or in a marina.
It's important to note that the use of quality oil for automix systems is critical, and it needs to be highly fluid at low temperatures and have excellent lubricating properties, so as not to clog the thin channels of the pump and injectors. Motul, Evinrude and Mercury They produce special oil lines designed specifically for such systems.
Always check the oil level in the tank before each outing, and even a small amount of oil can run out at the most inopportune moment away from shore.
Design and main components of the system
To better understand how to maintain your motor, it is useful to know what it consists of. car-mixThe main element is an oil pump, which is usually attached to the side of the carburetor or integrated into the cylinder block. Inside the pump is a plunger or gears, which are driven by a cable from the gas handle or a separate servo drive.
The second important component is an oil tank, often built into the top of a lower unit or placed under the hood of a motor, connected to the pump by a transparent hose, which allows visual monitoring of fluid levels. Fuel hose from tank to pump should be resistant to the aggressive effects of oils and not tan in the cold.
In complex electronic systems, you can find additional sensors and solenoid valves that control the oil supply with high precision, opening and closing thousands of times per minute, a design that is typical of high-powered motors, where environmental and reliability requirements are highest.
Below is a table comparing the main types of oil supply systems in two-stroke motors:
| Parameter | Hand-mixing | Mechanical automix | Electronic car mix |
|---|---|---|---|
| Dosage accuracy | Medium | High. | Maximum |
| Electrical dependency | No. | No. | Yes. |
| Complexity of service | Low. | Medium | High. |
| Risk of user error | Highly | Low. | Low. |
How to properly set up and pump the system
After replacing the oil pump, hoses or completely emptying the tank, the system requires mandatory pumping. oil-pump This is not acceptable, because it will lead to oil starvation and jamming of the engine. The pumping process may vary depending on the model of the engine, but the general principle is the same.
Usually, on or near the pump body is a propeller for air ejection. You will need to unscrew it half-bore and slowly apply the oil (manually or by turning on the starter if the design allows pumping without starting) until the liquid without bubbles comes out of the hole. yamaha and tohatsu Often have special maintenance regimes for this procedure.
☑️ Checking the automix system before the season
The tension adjustment of the pump drive cable is another critical point: if the cable is pulled over, the motor will eat oil and smoke. If it is not pulled, there will be a risk of overheating. The pump body usually has tags that must match in a certain position of the throttle valve (often idling or fully open gas).
⚠️ Attention: Before adjusting the oil pump drive cable, make sure that the throttle lever on the carburetor and the gas handle on the tiller are synchronized.
Typical malfunctions and methods of their elimination
Despite the reliability of the system mixer The most common problem is the suffocation of the main line, and if you notice that the oil level in the tank does not decrease after a long period of operation, or the engine starts to detonate, the first thing you do is check the hoses for leakage and air bubbles.
The second common cause is that the pump plunger is jammed due to poor-quality oil or prolonged downtime, and the oil can coke and turn into tar, in which case the pump requires disassembly, cleaning with a special solvent, and replacing worn-out parts.
- 💨 Smoke from exhaust: A sign of too rich a mixture (lots of oil) or oil entering the combustion chamber through the coils.
- 🔊 Engine knock: A possible sign of oil starvation due to pump malfunction.
- 📉 Power drop: may indicate an incorrect adjustment of mixing proportions.
You should also pay attention to the condition of the spark plugs, because if they are black and wet with oil, then the system is supplying too much of it, and if the candles are white-colored or melted, this is a sure sign of a lack of lubrication, which requires immediate intervention.
What happens if the oil in the tank of the car mix runs out?
Most modern motors have an oil level sensor, and if the oil runs out, the engine will either go into emergency mode (revving restriction) or an audible alarm will go off. But you can't rely on electronics alone, because there may be some time between the moment the sensor is triggered and the oil is completely stopped, during which time the engine will run on the residue of oil in the mainline, which may be enough for a few minutes of operation, but the risk of piston bully remains high.
Choosing oil for systems with automix
Not all oils are equally good for your motor. Viscosity and the ability to emulsify with gasoline are critical for automatic-feed systems. Using thick oils designed for manual mixing can cause the pump to simply not be able to pump fluid through narrow channels.
Look for the markings on the canister. TC-W3 It's the standard for two-stroke water-cooled motors, and manufacturers often say "For Oil Injection" or "For lubrication systems." Mercury, Quicksilver and Evinrude They are often color-coded (blue or red) so you can visually distinguish them from gasoline in the event of a leak.
Synthetic oils are preferred over mineral oils, as they leave less sodium and mix better, but if you are switching from mineral oil to synthetics, it is advisable to pre-rinse the system or to develop the residues of old oil to a minimum to avoid stratification of the components.
Use only the oils recommended by your engine manufacturer, and experimenting with cheap ones can lead to costly repairs to the piston group.
Can I mix different brands of oils in a tank of car mix?
Technically, if both oils are TC-W3 based and have the same base (both synthetic or both mineral), short-term mixing is acceptable. However, manufacturers do not recommend, since different additive packages can react chemically to form a precipitate.
How often should you change the oil in the car mix system?
The oil in the system does not change in the usual sense, as in a 4T engine, it is consumed. However, if the engine was long (more than a season), the oil in the tank and pump could lose its properties or dissect, in which case it is recommended to drain the old oil, wash the system and pour fresh.
Why does the engine smoke at idle speed?
At idle speeds, the automix system supplies a minimum amount of oil, but if the smoke is excessive and has a blue tint, the adjustment of the pump cable may be disturbed (provides a lot of oil at a minimum) or the crankshaft coils that allow oil to enter the combustion chamber are worn out.
Do I need to warm up the motor with an automix before starting the movement?
Yes, warming up is mandatory. Although the pump starts working immediately, the oil takes time to fill all the highways and lubricate the rubbing vapors. Let the engine run at idle speeds for 2-3 minutes after starting, before giving the gas.
What is the resource of the oil pump automix?
With quality oil and timely maintenance, the pump's life is comparable to that of the engine itself, with the main enemies of the pump being dirt in the oil, water in the tank, and long downtime without preservation.