Outdoor Power Equipment and Small Engines - Seasonal Oil Change....

Is it better to replace crankcase oil in lawn equipment before winter storage or...do it in spring? Im concerned about moisture contamination in the oil due to condensation from temperature fluctuations throughout the winter months of storage?

Thanks,
Ken S.

Hello Ken!

That is a good question...and one that will get responses with valid reasons to do it both ways. When the unit sets idle for a few months, the contaminants in the oil will settle to the bottom of the engine creating a sludge film. This is why I say changing it at the end of the season before storage is best. On the other hand, condensation, like you mentioned, could be a potential problem in some areas. Check for water or milky colored oil on the dipstick before you start the engine in the spring. If you see it, then change the oil again. If you don't, then run it for a few minutes and check it again. If it is still clear, then you should be OK. The main way to avoid all of this, and many other problems like gummed up carbs, sticky linkages, dead batteries, etc... is to start the engine every 2 to 4 weeks during the off-season and let it run for a few minutes. This is the best way to avoid spring-time troubles with your mower.

Hope this helps!

Definitely before storage and if you're concerned about the condition of the oil in the spring, change it again. And don't forget the fuel stabilizer in the gas tank.

My $.02 worth.

I agree. Oil is a buck a quart. Cheaper than a new machine :)