Now that you have a new generator, there are some specific steps that you need to do before you ever start it up for the first time to ensure that your generator will reliably last for years. These break-in steps are the same, no matter if you have a small 2000 watt inverter generator or a larger 10,000 watt open frame whole-house generator.
Take my advice, don't just do the minimal steps outlined in your user manual to get your generator ready. Take the extra time to perform all of these steps and you will be able to get many more years out of the life of your generator.
Before you even start breaking in your generator, you need to get some supplies. You will need engine oil for the break in period. Don't worry about getting expensive oil for this as we will be replacing it several times very soon. Depending on your generator, this will take somewhere between 3 to 4 quarts total.
You will need something to drain the oil into when you change it out. I recommend using the clear Glad flat disposable 25 ounce bowls. They are short which makes getting it under the generator easier, and with them being flat and clear, you can see through the used oil easier which you will see in a few minutes comes in handy as we inspect the used oil. They are also cheap, and you will need 3 of them so go ahead and buy the 5-pack for about $10.
You will also need a new spark plug. I recommend replacing the cheap spark plug that comes in the cheaper generators with an NGK sparkplug. You can go to an auto parts store to have them cross reference the sparkplug that came in your generator with the correct NGK replacement number, or you can use this website to cross reference it yourself at the link below: http://progreengrass.com/spark-plug-cross-reference-chart/
You will also need a bottle of Lucas Heavy Duty Oil Stabilizer and a good high-quality full-synthetic engine oil that will be left in the generator when we are finished breaking it in. I recommend Royal Purple for this. Check your owners manual for the viscosity, most generators recommend a 5W-30 oil. Luckily you will only need one quart of this one because it will be more expensive than the cheaper break-in oil that you will be using, but it is well worth it for the additional protection that it will be giving your generator.
I highly suggest adding an hour meter if your generator did not come with one supplied already. This takes the guesswork out of generator maintenance by letting you know exactly how much run time your generator has on it. They are available from Amazon for about $12.
They are cheap and extremely easy to install by simply wrapping the end of the supplied wire around the sparkplug wire five times and holding it in place with the supplied zip-tie. Route the remainder of the wire away from anywhere where it may get damaged from heat, abbrasion, etc. to where you want to mount the meter. Place the other end of the wire through the slot running along the back of the meter. Use the two supplied screws or use 3M double sided tape to attach the meter to the generator. The meter is powered directly from the generator so there are no batteries to ever worry about replacing.
I also highly recommend replacing the stock plastic oil dipstick on the generator with an aftermarket magnetic dipstick. These dipsticks are higher quality with knurled finger grips making them easier to get on and off, but they also have a very strong magnet on the end to catch any metal filings that may be floating around in your oil.
Ok, now that you have your supplies, lets get to breaking that generator in.
Remove the spark plug from the generator. Pour a very small amount of Lucas Oil Stabilizer into the hole in the top of the combustion chamber where you just removed the spark plug from. Then slowly pull the starting cord for the engine about 10 times to ensure that the cylendar wall is thoroughly coated before it is started up for the first time. Then replace the original spark plug,
Remove the oil dipstick and add about 2 ounces of Lucas Oil Stabilizer and then fill the remainder of the engine oil per the instructions in the user manual of your generator making sure that you do not overfill the oil. On most generators the oil should come to the bottom of the dipstick threads and will generally take between 11 to 20 ounces of oil depending on the generator.
Start the generator and let it run without a load at low idle in Eco Mode if it has one for 30 minutes. Then drain the oil out into a container. You will notice a lot of silver sparkles in the oil, these are metal shavings from inside the engine that we need to make sure are out of the engine before they cause damage to it.