Home Generator Repair

Reader Contribution by Ed Essex
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Generators are an important aspect of most homesteads and off grid living.  Our smallest generator is a 3500 watt portable unit that we use to top off our batteries or haul around the property for projects that might be a little out of range for our battery operated power tools.

I have no idea how many hours we have on it but it was purchased in 2008 and used extensively to build our house, keep our batteries charged on cloudy days and most importantly to run our 240 volt deep-well water pump. The water pump maxed out the generator capacity. This past year it finally gave out and could no longer produce electricity the way it was supposed to. It would work erratically on and off and anywhere from 50% voltage to 100 percent.

We live over 100 miles (200 miles round trip) from the nearest generator repair shop. By the time you take it there, pay the repair bill, and go back to pick it up you might as well buy a new one with ALL new parts.

I am the least mechanically inclined person I know and electrical is way out of my league but with nothing to lose I decided to do what I could to get this necessary piece of equipment up and running again.

I went online to You Tube and searched for a video that described my generator problems and ended up with a video from the Generator Guru. This video described how to remove the cover plate to expose the electrical wiring and parts that were directly responsible for generating power. It then goes on to lay out a step by step series of tests you can do with a voltage meter or multi meter to diagnose which part is not working properly. It also gives you the voltage parameters you will be looking for on each test.

These are the steps I took to diagnose my generators problem:

1. Disconnect the AVR (automatic voltage regulator) – this is so you can get raw real voltage data on steps 2-5.

2. Test the voltage for the brushes – this might tell you if you need new brushes or not.

3. Test the voltage on L1 and L2 – these might tell you if you need new windings or not

4. Test the voltage on RI and R2 – these will tell you if the rotor is bad or not.

5. Test L1 and R1 – this test has to do with the 240V option my generator has.

I did my tests and wrote the voltages down for each of the above items and called the National Support Hotline for my brand of generator. I described how the generator was behaving and gave them the voltage test results. (It should be noted that even though some of my results were outside the parameters given in the video it didn’t mean those parts were bad – i.e. the video said the voltage for brushes should be between 5v and 10v. Mine was 19v but my support hotline said that was okay for my generator).

The support person immediately diagnosed that the AVR was bad and I needed a new one. I purchased it right there on the phone for $31.00 including shipping. The AVR arrived at the post office box a few days later. It only took about 10 minutes to install and my generator once again performs perfectly. I virtually saved myself the cost of a new generator which would run around $350.00.

I would like to caution you that there are many more things that can go wrong with a generator, including bad spark plugs,  bad outlets, bad switches, and more. This article is not intended to cover all of the bases but it might just be a good place to start. It worked for me and I can guarantee you one thing – if I can do it, so can you.

Ed and Laurie Essex live off grid in the Okanogan Highlands of Washington State where they operate their websiteGood Ideas for LifeandOff Grid Works.

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