Oil change frequency

“How often should I change my oil in my lawn mower?” This is one of the more common questions we are asked.  The basic response we give is…once a year.  However, that is only a “rule of thumb.” The more complete answer should be: “Consult your operators manual” Each engine manufacturer will have their own specific recommendation about the proper interval between oil changes for their engines.  We have seen these vary between 25 hours and 100 hours depending on the manufacturer and the intended purpose of the machine. If you don’t have your manual anymore, here are some links that may help: http://engines.honda.com/parts-and-support/owners-manuals/ http://www.kohlerengines.com/manuals/landing.htm http://www.briggsandstratton.com/us/en/support/manuals Basically every manufacturer suggests that regardless of the number of hours put on the machine, the oil should be changed at least once a year. There is also one other important piece of information that manufacturer suggest (and that is widely ignored):  the oil should be changed after the first 5 hours of operation.  During the manufacturing process, small imperfections can develop on the machined parts.  During the first few hours of operation, these are ground off and the shavings end up in the oil.  By changing the oil after 5 hours, these shavings (and the damage they can do to high tolerance parts) can be eliminated).   What kind of use does the engine get? If the machine is used in dusty/dirty conditions, you should change the oil more frequently.  Other conditions that will require the engine to work harder and contribute to oil break down are heavy/wet grass, steep/hilly terrain and high temperatures.   What kind of oil should be used? We...