Pretty straight forward - the manual is quite helpful too - Warm the engine to normal operating temperature. Switch the engine off. Remove the cover and loosen or remove the fill cap. You will find the drain plug about halfway down the upper leg - the engine can be turned and tilted a little up so yo have best access, set a container underneath and unto the drain plug. Allow the oil to drain into the container, while this is happening undo the oil filter - it is a small spin on job similar to a cars - there is a large box type socket for these, but I found mine was a waste of metal as the sort of vague nut shape of the filter just rounded off, so I just use a regular small filter wrench. Drop that in your container for re-cycling with the oil and get your new filter out, make sure the old filter's neoprene gasket came off with the filter by wiping the seating surface with a clean rag, smear a bit of clean engine oil on the new gasket face on the new filter, and spin it on until it contacts the sealing face, tighten another 2/3rds of a turn. By now the oil should have drained fully enough for you to replace the drain plug - remove the old sealing washer and fit a new one, tighten firmly but don't be silly - you don't need to jump on the socket wrench. Re-fill the engine with the correct volume of specified lubricant - from memory 10W30. Re-fit the fill cap and start the engine, run just for a minute. Checking that the engine is vertical, not tilted or leaning any, check the oil level - when changing the filter it is normal for the level to be a little down, top up to the upper mark, but no higher. Make sure there is no leaks from the oil filter seal, wipe any oil residue up with rags and re-cycle the oil. Job done for 100 hours or 12 months, whichever comes first.
While you are there check the gearbox oil level and condition - replace oil and/or seals if needed, always replace drain plug sealing washers - they are very cheap, buy a dozen. Good time to swap out spark plugs if eroded and check any fuel filters, fittings, electrical terminals etc. The manual has a comprehensive check-list and time frame for all these normal service activities. 100 hours is roughly the same as 10,000km in a family car, and like your car, if the engine is flogged it may need more frequent oil changes, on the other hand if you idle the engine 80% of the time it is possible to extend the interval - however that is not something to do within the warranty period and is irrelevant outside 12 months since the last service. As a commercial operator I would do 10 to 15 oil changes a year, half a dozen or so with my diesels - but that is the sort of hours you do professionally. Knowing exactly how my engines were being used allowed me some flexibility on oil change intervals, and my older engines run like a swiss watch, use negligible oil between services and go just fine 100% of the time with 4000 plus hours on them. I would expect at least 5000 hours out of a modern four stroke in commercial use, but for recreational use it will always be rot and corrosion that kills them, not the hours. I only ever had trouble with engines that got parked for whatever reason - ever.
Good luck.
asian hairreptiles
