When I was in the military I was in charge of some very large maintenance operations. One of my maintenance assignments was in a communications Battalion that had hundreds of generators to service and maintain. When we conducted monthly preventive maintenance checks and services the generator operators were required to start and run the generator sets with a load, to prevent starting and running issues caused by sitting idle for too long. You might say this was my early indoctrination in generator care and maintenance. Today we are going to look at what you can do to protect your generator when it is in storage.
When I worked for an RV dealership every spring I noticed the service department was booked with appointments for generators that either wouldn’t start, or if they did start had that all too familiar surging sound. I immediately knew this was a result of letting the generator sit in storage without starting and exercising the generator.
It might seem odd, but the lack of use is one of the biggest problems with gasoline generators. Fuel can start to break-down in a couple of months. When a generator sits for months at a time the fuel starts to varnish and gum-up, resulting in hard-starting and surging problems.
Fuel related problems are the number one reason for exercising the generator, but there are other reasons too. Moisture build-up can result in damage to the generator. When you exercise the generator, it heats up the generator windings and eliminates moisture. And, it helps lubricate the engine seals and internal components, which can prevent carbon build-up. That is 3 good reasons to exercise your generator, but how do you go about doing it?
That’s a good question
Safety First! Whenever you are working on, or using your generator there is a threat of carbon monoxide poisoning. Always inspect the generator exhaust system prior to using it. Do not operate a generator with a damaged exhaust system. If you are using a portable generator set make sure the exhaust is directed well away from the camping area. Test your carbon monoxide detector for proper operation prior to using the generator.
Another thing you might find odd about generators is, they are designed and intended to run with a load, as opposed to no load. By load I mean an electrical load. Generators are rated in kilowatts (KW). One kilowatt equals 1,000 watts. So, a 4 KW generator would be a 4,000-watt generator.
Onan recommends running the generator 2 hours every month at 50% load, and up to a full rated load if practical.
So, as an example, you would exercise a 4000-watt generator with a minimum 2000-watt load. This is roughly equivalent to running one RV air conditioner, or a small portable electric heater.
Caution: Do not use a portable electric heater that is rated higher than 1500 watts, and do not run a 1500 watt heater continuously. If the heater is used for long periods of time set it on a lower setting, and do not leave it on unattended. When you purchase a portable heater make sure it has a tip-over feature where it shuts off it is bumped or tipped. Follow all operating instructions that come with the heater.
It’s always better to exercise the generator for longer periods of time with more load than it is to run it for short time periods with little or no load.
Check your generator owner’s manual for load ratings specific to your generator. If you do not have the owner’s manual you should be able to locate one online.
In addition to the monthly exercise regime I recommend you use a fuel preservative to help protect the entire fuel system when the generator is in storage. Follow the manufacturer instructions for using fuel preservatives.
Using fuel preservatives applies to any gas-powered items you have sitting in storage at home like lawnmowers, weed-eaters and ATVs. A good habit to get into is to add the correct amount of preservative to the gas can every time you fill it with gas.
These generator problems mostly occur when the generator sits in storage for months at a time. If you have not started and ran your generator with a load on it in the last month or two, now would be a good time to do it. Following these simple steps and routine generator maintenance will keep your generator in top operating condition.