"Break-in oil" is an ambiguous term or figure of speech. Specifically it refers to "the first batch of oil" placed in the engine when the engine is new or has been overhauled. Some OEM's will use a somewhat "lighter or less viscous" oil for this initial "run-in" period, other OEM's will simply put it what they recommend for typical use right from the start. The real purpose of "break-in" oil is wash down the interior surfaces of the engine to remove and carry away any "assembly debris" or metallic particles that might be shed as the new components wear or rub into each other in the short time immediately following the first start and run cycle of the engine. Why don't you simply go ahead and simulate a "1 hour power outage" so the engine will run for an hour uninterrupted. After that, change the oil to the recommended specs. Be sure to read the manual in regard to setting the generator to "Maintenance safe mode" or whatever your OEM calls it. Normally they configure the auto controls so that when it is necessary to do routine maintenance, the generator is "Locked out" and cannot be activated while work is being done. Remember to reset it to auto stand-by mode when you are finished.

Thanks for the informative reply, Mownie. That is a great suggestion. And yes, there is a switch position to put the generator in while doing routine maintenance and the process is described in the manual.

I would do as Mowie recommended and get the break-in oil out as soon as possible.
There is allways the possibility that a power outage might catch you running the unit , on break-in oil , for 40-70 hrs before the power is restored.

When to change 'break-in' oil? when stop using oil from new no sooner are ring will not be seated. If do it before seat it take long time to seat are allways be oil user. I have known manufactors using 20 wt. for brakein oil. Once ring seat end the gap give all rings oil needed.

That would make a good topic for Myth Busters if it hadn't already been debunked in the past.

A few years ago I bought a chipper with a 10 horsepower Briggs & Stratton. It said to drain the break-in oil after 5 hours.

The recommended break-in run time on the equipment that I have owned has been between 3 and 8 hours. At 10-12 minutes per week, we're talking 8.6-10.4 hours per year. Even though the manual suggests changing oil annually, I'd change the break-in oil at around 6 months. After that, oil changes at one year intervals will be often enough.

-Deerslayer

Thanks all for your replies!

It just occurred to me that I should have mentioned in the original post that this automatic generator runs on natural gas, NOT gasoline, which was one of the reasons we went this route. In the event of an extended power outage, I didn't want to have to be concerned about how to get more gasoline. Does that make any difference?

Thanks again,
John

Natural gas is cleaner burning than gasoline. Because of this, I think it will contaminate your oil less than gasoline.

In any case, a one year oil change interval is reasonable provided that you don't exceed 50 hours of run time if the engine has an oil filter or 25 hours if it doesn't.

-Deerslayer

Thanks a lot, Deerslayer. The engine does have an oil filter so I guess after this first oil change, I'll change it once a year unless the power goes out!

Wow, it works! I don't know why (no storms or anything) but the power went out this morning for about 4 hours and the generator kicked it after 30 seconds just like it was supposed to! I guess I didn't spend all that money for nothing after all!

Keep on smiling. NG is a great fuel for this application (unless the gas supply is interrupted). For folks who may not have natural gas service on their street, but would like most of the advantages of NG, Propane is a viable alternative. People who already heat or cook with propane (from a bulk cylinder on premises) have a fuel supply already in place. Other folks would need to transport small tanks of propane but the big advantages are in the clean burn and that the fuel never deteriorates (unlike gasoline).

That's all true, Mownie. The generator came all set up for natural gas but the instructions included a section detailing exactly what needed to be done to change it to propane. I have never used a portable generator but it sure is nice not to have to worry about a fuel supply for it!

Glad to hear that your generator worked as planned. Since you have about 5 hours of run time on it, I suggest that you change the break-in oil now. You may experience another outage in the near future that could last longer.

-Deerslayer

Thanks, Deerslayer. I changed the oil and filter today!