Why Small Engines Will Not Start in Spring
Stale fuel is why most mowers, strimmers and generators fail after storage. What happens inside the carburettor, and the two storage methods that prevent it.
Guide
Outdoor machines · OM-01
Lawn Mower Service Log
A free printable lawn mower service log — oil, air filter, spark plug and blade record, with a specification block and end-of-season storage checklist.
Download Free · no sign-up
2 pages. Choose your paper size — both versions are laid out identically, so neither one gets shrunk to fit.
Print it and write on it
Fill it in type and save
The fillable versions have real form fields — open them in any PDF reader, type into them and save. Printing help.
What this sheet is for
Keep a mower running past its fifth year, by tracking the three things that actually kill them: stale fuel, a blocked air filter and neglected oil.
Who it is for
Anyone with a petrol walk-behind or ride-on mower.
How to use it
- Fill in the specification block once — oil type, plug gap, filter and blade part numbers — so you never look them up again.
- Log each service with the date and season or hours.
- Work through the end-of-season list before storage, not in spring.
- Sharpen or replace the blade at least once a season.
What is on the sheet
The layout is fixed at a size that fits both A4 and US Letter, so the A4 and Letter files are visually identical and print at full size on either. Rows are set at a height that an adult can actually write a date and a few words into with a pen — most printable tables are built in a word processor and never tested with one.
Questions
Why does fuel matter so much?
Petrol degrades in storage, and modern fuel containing ethanol degrades faster and attracts water. The result is a gummed carburettor, which is the single most common reason a mower will not start in spring. Either run it dry or treat the fuel.
How often should the oil be changed?
Small engine manufacturers usually specify hours of use as well as an annual change. Check your handbook and record the interval in the specification block.
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One new sheet, most weeks
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