Empty the Gas Tank
This is especially true in cold climates where the fuel is likely to freeze in the tank. No quicker way than destroying a lawnmower than having the fuel freeze in the tank. There are lots of easy guides on how to empty your gas tank efficiently online and there is even one on this blog.
Drain the Oil
Pretty much same reasons as above not to mention when you are reusing your lawnmower, fresh oil is always better. You can find an easy step by step guide on this blog furthur down.
Clean the Undercarrage
Use a putty knife and wire brush to scrape off the grass and mud caked on the mower deck. his prevents rust, clears the passageway to the discharge chute and allows the aerodynamics of the deck to work as designed.
Store in a Dry Place
Storing in a dry place ensure water damage will not occur. Water damage can cause irreparable damage to the lawnmower or at least make it that a new lawnmower would be less expensive than the repair costs.
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