DIY! “How to Fill Engine Oil” Part 3 Taught by Professional Mechanic

Engine oil is degraded by rising oil temperature or blow-by gas, so it needs regular replacement. The 2003 model YAMAHA SR400 engine oil has a viscosity of 10W-40 and a capacity of 2 liters. If the oil filter is to be replaced at the same time, it will be 2.1 liters. By performing the most basic and important maintenance yourself, you will surely improve your attachment and understanding.

 

Since the oil injection port of the SR400 is located lower than the upper surface of the gasoline tank, the funnel should be used so as not to spill oil. If there is no funnel, it is also possible to cut the plastic bottle.

  1. SR400 style is to inject oil into a frame pipe

▲ If the cut plastic bottle is replaced with funnel, the oil will not be spilled from the inlet and become dirty. The work efficiency is increased with just a little effort.

An increase in oil temperature is a major cause of engine oil deterioration. Generally, when the oil temperature rises to 40 degree celcius to 60 degree celcius, the viscosity of the oil and the additives will be able to achieve the specified performance. It rises as it is, and the internal component of the oil begins to deteriorate under the damage per which exceeds 130 degree celsius to 140 degree celcius.

If it is a liquid-cooled engine, the proper temperature is maintained by cooling water, but only the traveled wind depends on the outside air. In severe conditions such as heavy roads in the summer, the temperature can rise to over 120 degree celcius, so if you change the temperature during the season, you can increase the life of the engine.

We introduced in Part 1 [DIY! "How to Change Oil"...] that there is wet sump and dry sump method to manage the lubricating engine oil. In the case of dry sump, there is an oil tank separate from the engine body, and the SR400 uses the frame down tube as the oil tank. Therefore, the new engine oil is injected from the back of the top bridge.

 

  2. OEM oil for motorcycle manufacturers that can be used safely

Choosing the manufacturer or brand of the oil to be replaced is one of the pleasures of the engine oil change. Even on our Webike shopping sites, engine oil is always a popular category.

The difference between base oils such as synthetic oil and mineral oil, the difference in viscosity, selling points, price, etc. are too many, and I worry that I can not choose the opposite. It is the OEM oil with the label of the motorcycle manufacturer that is recommended in such a case.

In the case of YAMAHA, we have a lineup of products used in general maintenance, from engine oil to chemicals, under the YAMALUBE brand. As a motorcycle manufacturer, some people think that there are no features in terms of performance or price, and it is not possible to do so, but in fact, the original oil of the manufacturer is a high-performance product developed by making use of the standpoint that knows the characteristics of the motorcycle company the most.

For SR400, the following are possible to use.

・High-performance chemical synthetic oil "Premium Synthetic"

・Well balance of partial synthetic oil "sports"

・Basic mineral oil "Standard Plus"

If it is narrowed down to 3 types of engine oil in a large amount, it might be a bit of a surprise to choose a product.

 

Oil viscosity is important along with brand name

The specified viscosity of the SR400 is 10W-40, and all of the 3 YAMALUBE brands are 10W-40. A brief description of the oil viscosity indicates that the "10W" of 10W-40 has a low viscosity at low oil temperatures, and a low number indicates a low viscosity at low temperatures. On the other hand, "40" in the latter half shows the viscosity of the oil at the temperature of 60 to 80 degree celcius or higher, and the viscosity is one of the factors of the oil film strength of the oil, so there is an idea that the higher viscosity of the high temperature side in the air-cooled engine in the summer is safe.

However, when the viscosity of the oil is increased, the friction increases as a disadvantage in exchange for the strength of the oil film. Whether or not you notice the difference depends on the type of engine and the way you ride it, but it may be perceived as a dullness of the rise of the engine rotation. However, OEM oil of the motorcycle manufacturer is tested under very severe conditions at the time of vehicle development, and it has been developed so that the performance does not deteriorate even if the oil temperature rises.

The fact that it bears the emblem of YAMAHA means that there is so much confidence in it. "Use OEM oil if you doubt" can be said to be a safer choice to change the modern engine oil.

 

  3. Fine-tune with level gauge when you inject it to near the specified amount

▲ To prevent over-filling, check the oil level with the dipstick when it becomes close to the prescribed amount. For SR400, you are instructed to check the oil cap without screwing it.

The SR400, which uses a frame down tube as an oil tank, has an oil inlet at the rear of the top bridge. This is a valley between the top bridge and the gasoline tank but by replacing the cut plastic bottle with a funnel, new oil can be injected without spilling. It is best to do if you have an exclusive funnel, and it is something that works even more than you thought.

The oil capacity of the SR400 is 2 liters when replacing only oil, and 2.1 liters when changing the oil filter at the same time. You need 0.1 litres of oil to circulate in the filter case. When the oil is filled into the plastic bottle instead of funnel, do not put it at once so that it does not blow back from the inlet, and pour it gradually.

When pouring from a one-liter can, you can pour the 1st can until it is empty, but you can't inject the 2nd can, and when you're about 0.2 liters left, remove the funnel. Insert an oil dipstick with the oil cap to check whether the oil adheres, and pour a little more if it does not stick. When checking the oil level with dipstick, it is necessary to place the vehicle in a flat place as much as possible.

Since the capacity of replacing the oil filter is 2.1 liters, it seems to be good to inject all the 2nd oil can, but let's check with the dipstick from the end of the 2nd oil can. Once the oil level reaches the middle of the dipstick, tighten the cap at once to start the engine, and after idling for about ２to３ minutes, check the oil level by the dipstick again. Since there are many cases when the level is lowered by starting the engine and the oil circulates, the shortage will be added at end of the work.

The dipstick has a lower and upper width, but it does not need to be put up to the upper limit if it exceeds the lower limit line. In the case of wet sump, when the engine oil is stored in the crankcase, it is necessary to pay attention to the fact that when the oil level is set to the upper limit, the pressure in the crankcase increases, and the oil may be spewed from the breather hose.

 

  Enjoy a comfortable bike life by periodically changing your engine oil according to the mileage

By regularly changing the oil that is the blood of the engine, the rotation becomes smooth, the shift change becomes smooth, and the life of the bike is also extended as a result, so maintenance should be done according to the mileage.

 

 

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