Preventive Maintenance (PM) is maintenance the owner can perform on your RV before a problem exists. These checks are designed to prevent or identify potential problems that could lead to mechanical breakdown, malfunction or failure of a component or system on your RV. Preventive Maintenance consists of cleaning, inspecting, lubricating, adjusting and servicing your RV.

Whether it’s a portable generator you use around the house or the generator in your RV here are some simple PM checks you can perform to keep it in top operating condition. In addition to these PM checks you should always follow the maintenance and service schedule guidelines that came with your specific generator set.

* Safety First! Always check the exhaust system prior to starting the generator. A damaged exhaust system can result in carbon monoxide gas getting inside the RV. Inspect the entire generator exhaust system. Never operate a generator with a damaged exhaust system!

* Always check the oil level prior to starting the generator. Starting and running a generator that is low on oil can result in costly damage to the generator’s engine. Add the proper type of oil as required

* Keep the generator set and the compartment it is housed in clean. You can use compressed air to assist in cleaning out the generator compartment and a clean shop rag to clean the generator set. While you are cleaning the generator check all electrical connectors for secure connections.

Note: Always wear safety glasses when using compressed air.

* Check all of the filters on the generator. A typical generator may have an air filter, fuel filter and oil filter. Check your generator owner’s manual for the types of filters your generator has and where they are located. Dirty filters will affect the operation of your gen set.

* Maintenance checks and services for a generator are based on hours of operation. Monitor the hour meter on your generator set and keep track of all maintenance intervals.

* Change the oil and oil filter (if equipped). This is perhaps the most important PM Service you can make on your generator to ensure years of reliable service. Change the oil and replace the oil filter at the recommended intervals. If you don’t feel comfortable changing the oil and filter have an authorized RV service center do it for you.

* Exercise the generator. There are several reasons why you should start and exercise the generator set on a regular basis. Moisture build up can cause damage to your generator. When you exercise your generator it heats up the generator windings and eliminates this moisture build up. This monthly exercise regime also lubricates all of the engine seals and components and helps to prevent carbon build up. When you exercise the generator it should have a minimum 1/2 rated load on it, and it should run for at least two hours every month. Check your generator owner’s manual for load ratings specific to your unit.

* Add a fuel stabilizer to the motorhomes or generator’s gas tank and run the generator long enough for the stabilizer to get through the entire fuel system. This will help prevent gas related problems on generators, like not starting or surging. Fuel stabilizers can protect the fuel system for up to six months or longer, but keep in mind the importance of exercising the generator too.

Follow these simple PM checks, and the maintenance and service instructions in the generator owner’s manual, and you can get years of reliable, trouble-free service from your generator set.

Happy Camping,

Mark Polk

RV Education 101

RV University

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  1. Ham Radio

    Great tips, everyone.
    We run synthetic oil at the recommended weights for our gennys. Over several years of hard usage, including portable models for emergency communications, we have never had one failure under extreme extended run usage, all weather.

  2. Michael

    Forgot to mention thesemotors were in 32 ft boats. But the priciple applies to cars also.

  3. Michael

    I agree with Frank. When I was working for the great state of ???? every time we changed the motor oil in our police cruisers we replaced 1 qt of oil with marvel mystery oil. Damn motors rang like a swiss clock.

  4. Don Ackerman

    For any prolonged times in between usage, I would highly recommend a fuel stabilizer. I learned this the expensive way on my 1st coach, after the carb repeatedly varnished-up and had to be worked-on by my RV repair guys. Also, as mentioned, getting the gas out of the carb helps and the pressure out of the entire system. Onan now has an electric primer on newer models, that you depress prior to starting your genset, in response to so many consumer problems and requests. It works great.

  5. I use a product in my boat and other items that have long times between use, it works so well its comparable to starting your engine with synthetic oil at 20 below instead of 30 weight. After sitting for a long time the engine fires up like you used it yesterday, it is amazing how well this stuff works,This product has been around for years its called Marvel Mystery oil, you add 4 oz of it to 10 gallons of gas, it helps stabelize the gas and most importantly it is a top end lub for the engine, when it combusts it turns to water actually giveing you a slight boost. I have a friend that buys it in 50 gal. drums for some antique aircraft that he maintains, when you go inverted with them the oil pump is in the bottom and the engine is starved for oil, by using this stuff it prevents the engine from being damaged. I am reasonable certain that it is not an approved product for this purpose, You should give it a try, the cost for a half gallon is around $10, Note the difference in starting after this has been in the system, you can actually tell it works :>)

  6. Chris

    Another tip is to run the carb dry when you shut the generator off. Just close the gas valve and let her run until the fuel in the carb is depleted.

    We had been having trouble with the portable Honda generators on our firetrucks. Gas sloshing around in the carbs, when the truck was under way, was getting into the crankcase and contaminating the oil. Generators were not running at the time of course.

    Running the carbs dry after use prevented this. Yeah it takes a few extra yanks on the cord to refill the carb and get her runnin but thats OK.