Maintaining the Performance of the 2 Stroke Motor

Hello Bahari pals, in this discussion we will provide “Tips for Maintaining 2 Stroke Outboard Motor Performance”. We will use a Yamaha outboard motor type E40GMH as an example.

What does Outboard Motor Performance mean?

Maybe Bahari pals still doesn’t understand about the engine performance on the outboard motor, so what we will be discussed here is the engine performance in internal combustion or combustion in the engine itself.

What are the main factors for engine performance?

Bahari pals, there are three main factors that are important to maintain the performance of your outboard motor, the first is “Fuel”, the second is “Ignition”, and the last is “Compression”.

FUEL

As Bahari pals know, for those of you who already have an outboard motor of this type (2 Stoke), the fuel you usually use is mixed / pre-mix fuel, as explained in your outboard motor service manual book for comparison. Every 50 liters of fuel / gasoline mixed with 1 liter of Yamalube 2T oil or a ratio of 50:1.

When purchasing an outboard motor, you will get a gas / fuel tank for your outboard motorbike with capacity of 25 liters, so to mix Yamalube oil into the tank, you only need to mix as much as .5 liter. Remember, only mix oil into gasoline using Yamalube 2T oil, not with other brands of oil, because Yamalube 2T oil has been design by Yamaha engineers in Japan to extend the life of Bahari pals outboard motor components.

To measure how much oil will be mixed into the gas tank, for example, there are two bottles of 2T oil, namely Yamalube 1 liter capacity and Yamalube 0.5 liter capacity, so to mix Yamalube with fuel in the 25 liter tank, Bahari pals just need to use Yamalube with a capacity of 0.5 liters

How to measure the oil mixture for gasoline 1 liter, 2 liter, 5 liter and 10 liter ?

If Bahari pals has Yamalube 2T oil bottle with capacity of 1 liter, the Yamalube bottle cap has been measured, it turns out that the volume is 0,02 liter or comparable to 1 liter gasoline capacity. So in short, for Bahari pals who are still confused about how to measure the mixing of gasoline with oil in the field, just mix 1 liter of gasoline with Yamalube 2T oil. Then next if Bahari pals want to mix 5 liters gasoline, then proceed with mixing as much as 5 measures of bottle caps, and so on next for 10 liters of gasoline and so on.

Ignition

On the E40G engine, there is a part called the Spull (coil), then there is a reactfire, coil, a spark plug wire, then there are two spark plugs each for one cylinder. In short, so in the coil there is a coil with a magnet, and induction will occur when it rotates, which will produce an alternating electric current (AC), then the current flows into the reactfire component, in this component the current goes back and forth and then will be converted into direct current (DC), then the current that has been converted into this direction enters the next component, namely the coil, the DC current that was previously still small in size will be enlarged in this coil, then the enlarged current will enter the cable spark plugs and spark plugs will produce sparks. That was ignition in nutshell in Bahari pals Yamaha outboard motor.

One of the good factors of ignition on the outboard motor is the condition of the spark plug itself, so how about a good spark plug example? So the following is an example of a spark plug on an outboard motor that is still in a good condition, pals, on the E40 out outboard motor, this spark plug is type B7HS.

What must be considered for a spark plug that is in a good condition is the spark plug head, there is a curved electrode, and an upright electrode in the middle, and there is also a white insulator. Physically, a spark plug that in a good condition is the upright electrode in the middle and the one that curved, undamaged and clean, and make sure the insulator is still in intact condition, because if the insulator is damaged or not intact there will be an electric leakage.

If you don’t have a filler gauge tool, you can use a hacksaw blade like the image below to find out that the spark plug gap is still in good condition, this is because the hacksaw blade thickness is 0.69mm.

You can replace the spark plugs at sea, but there are a numerous of things to pay attention to, you have to prepare a spare spark plug to replaced, then you must have a spark plug key to open the outboard motor spark plug, and don’t forget to replace it when the wave conditions are calm. You also must pay attention to your own safety when replacing spark plugs when the sea is calm, so no accidents occur.

Steps to replace spark plugs at sea.

First, if the conditions are possible to replace the spark plugs, you can “Full Tilt” the outboard motor, which is lifting the outboard motor to an upright position, as shown.

If the outboard motor is already in full tilt position, then open the “Top Cowling”, if the Top Cowling has been opened, then Bahari pals only has to remove the spark plug that you want to replace with a new spark plug using the spark plug key that you have prepared beforehand. This spark plug replacement shouldn’t take a lot of time if you have already replaced the outboard motor spark plugs before.

Then if the spark plug has been replaced with a new one, you can return the trim position of the engine to a tilted propeller position, and start the outboard motor test, if the engine is already on, you can replace the top cowling of your outboard motor, then you can continue on your trip to the sea, friends.

Compression

Compression is the pressure in the combustion chamber that needed to compress the mixture of fuel, air and oil, so that when a spark occurs, this compression can kick the piston to perform power steps.

What happens if the outboard motor is not compressed? The engine will be difficult to start and the outboard engine will lack power.

How do you find an outboard motor with a good compression? You can pull the recoil starter, then feel if the pull is a bit heavy and dense, there is also like a burst of wind in the outboard motor, so you can be sure that the outboard motor has a good compression.

Conversely, if your starter recoil pull is light, you can be sure that the outboard motor has no compression.

Thus the article “Tips for maintaining the performance of a 2 stroke outboard motor”, if you want to see more details, please see the following video: