How long oil last sitting in a engine?

[Sawtooth]

So thinking about changing oil in lawnmower today and I'm curious that once the changes are made how long with the oil stay effective by sitting around? Thought I would change it now run it every couple weeks to warm up the engine and shut it down till season starts thoughts? Have several to do so I wanted to get started early. Thanks

 

[SHOZ]

I would change it and forget about starting it until you need to use it. Maybe a spark plug and air filter service if you are antsy?

 

[Kuato]

Your mower? Just change it and let it sit. Fire it up in the spring when the grass gets long.

At the end of the next mowing season, change it before you put it away. Done.

edit: I completely failed to answer your question! The oil will last indefinitely if it is just sitting. Starting it up for a short run probably won't help and may hurt it.

 

[Olas]

Don't start the engine unless you can run it up to full temperature. Starting the engine just to warm it up and keep things moving only gets it warm, which promotes condensation and rust.

Put it away hot and put fresh fuel in the next time you need to use it. It'll be fine.

 

[Linctex]

Agree with the above.

Also, oil just sitting in an engine doesn't go bad. I've started old farm equipment & old cars/trucks on whatever was already in the sump, some setting for 30 years or more.

 

[Bgallagher]

I have always changed the oil after the first warm up of the season. I warm up the engine, change the oil/filter. Take off the plug and either replace or clean it up, regap and call it a new season