For a gasoline generator you should start and run the generator with at least a half rated load for a minimum of two hours every month. It is extremely important that you run it with this minimum rated load. Generators are designed to run with a load placed on them. Our motor home has a 4,000 watt generator so I can either turn the roof air conditioner on in the summer time, which is about 2,000 watts or I can use a couple of small portable electric heaters if it's cold out. It's always better to let your generator run for longer periods than it is for short periods. Check your generator owner's manual for load ratings specific to your unit.
Other maintenance intervals for generators are based on usage. Your generator set will have an hour meter so you can monitor the usage. Consult your owner's manual for maintenance intervals.
Changing the oil and filters on a regular scheduled basis and for seasonal changes is just as important for your generator as it is for your automobile. For extended storage requirements consult your generator owner's manual.
Happy and Safe Camping,
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