Hour Meters, and Why Machines Are Serviced by Hours
Small engines, tractors, generators and boats are specified in running hours rather than dates. What an hour really measures, and how to track them without a meter.
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Outdoor machines · OM-03
Generator Service and Run Log
A free printable generator log — monthly exercise runs, run hours, fuel, oil and filter changes for a standby or portable generator.
Download Free · no sign-up
One page. 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
Make sure a standby generator actually starts when the power goes out, by recording the monthly exercise runs that keep it alive.
Who it is for
Anyone with a standby or portable generator — homes with unreliable supply, smallholdings, workshops and boats.
How to use it
- Record the specifications once, including run time at half load.
- Run it under load for around half an hour every month and log it.
- Change oil by hours as well as annually.
- Note fuel added and treat fuel that will be stored.
What is on the sheet
One page, top to bottom:
Printed under the title: Run hours, exercise runs and servicing for a standby or portable generator. A generator that has not been run since it was bought is the least reliable machine you own.
Exercise it monthly. Run it under load for half an hour every month. Generators fail from standing, not from working — carburettors gum, fuel goes stale, and batteries die quietly.
Write-on lines: Generator make & model · Serial number · Engine make & model · Purchased · Warranty ends
Specifications — look these up once and never search again
Write-on lines: Output (kW / kVA) · Fuel type · Tank capacity · Run time at half load · Engine oil type & qty · Oil change interval · Spark plug / gap · Air filter part no. · Fuel filter part no. · Battery type
Run and service log
Table, 7 rows: Date · Hours · Exercise run · Under load · Fuel added · Oil / filters · Work done / faults
Questions
Why run it if I do not need it?
Generators fail from standing, not from working. Carburettors gum up with stale fuel, batteries lose charge, and seals dry out. A monthly run under load is what keeps a standby unit reliable.
What does 'under load' mean?
Running the generator with something actually drawing power from it, rather than idling with nothing connected. Manufacturers usually specify a proportion of rated output — check yours.
Read next
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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.
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Also in the resources library
The same subject, with a version you can fill in on screen.
Equipment Running Hours Log
Hours run between one entry and the next, from the readings themselves.
LR-166 Log PDF Excel Online
