OPE Oil?

I remember at least 3 or 4 snowstorms that dumped snow over 2 feet in the last 30 years. We're probably due for another in the next few years. The last major snowstorm a snowblower would have been quite useful due to the volume of snow that fell.

As far as cold 5F temps, I recall that it was either Jan 2018 or Jan 2019 that my area got down to 5F for almost a whole day, and actually got down below 0F one morning. These are temperatures as reported on weather.com and are likely warmer than what they are at my house due to where they are measuring the temperature...

In winter, if the winds are calm, it is typically 9F colder where I live than it is 11 miles away in Manassas. I can see the outdoor temperature rise on my dash as I drive towards Manassas, and see it fall as I drive towards home. This is the so-called "urban heat island effect" in action. For example, it might be 39F in Manassas near the Costco on Sudley Manor Drive, but at my house in Nokesville, it's only 30F.
Ah, I see! You're to the West and out a bit, I'm to the South and right at the Beltway. Not so close to each other.
We really only get the bad stuff when it comes from the South.
"Suitable for air-cooled" , "suitable for small engines" and "specifically designed for the operating conditions of small engines" are all marketing terms. Small engines are not hard on oil, the only reason many burn oil is due to their sloppy tolerances and machining. You can run pretty much anything that resembles oil in a small engine and it will be fine, as long as the level is kept full especially in a splash-lubed engine. Certain oils like a 5w20 might burn off quicker than a HDEO 15w40 on a hot summer day simply due to oil temps and the sloppy tolerances, but that doesn't mean the oil is not suitable for the engine, as long as the level remains in the safe zone.

FWIW, I run 5w30 in snowblowers and 15w40 HDEO in pretty much everything else.
How many times has this been hashed over?! O.P
Must be getting old and forgetting :)
Or, if I go the highroad, maybe you are looking for new choices.

My BIG generator with a big OHV 389cc chinese honda clone on it would start knocking when hot on PCMO 10W30.

So way back when (2006?) I went to auto zone poked around and found they had some Valvoline Racing Synthetic 10W30. Drained the dino sludge and installed that and Voila ! NO more hot knocking when run over an hour.

A couple year later I added a shotglass of leftover Liqui Moly MoS2 that exploded my Honda fit engine.

That combo ran SUPER great for over ten years (same sump never changed!) then 2 years ago I decided to change the oil.

I didn't know what to run. Walmart had a bottle of Valvoline 5W40 Euro spec so I grabbed that. I was going to run M1 0W-40 FS but that got used as topoff oil in my turbo Jetta lease.

I HIGHLY recommend the Valvoline Racing Synthetic 10W30 but it's hard to find.

You will love the colour! it's dyed.

- Ken
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What makes an oil an air cooled OPE oil? Well, in my mind, you have to first withstand the heat. Two ways to do that is to use dino oil and change it often, or use syn/HDEO diesel oil that is rated for gas engines. Also, heavier is better for air cooled OPE. Some may disagree, but at least Kawi, and B&S have started recommending 15W50 oils in their latest recommendations. Also, any OPE oil usually has a pretty good dose of zinc in it. That's a good thing to look for and diesel oils with gas rating are good oils for this.
Having said all that, there is something else to remember. Air cooled OPE engines are overbuilt and under stressed for the jobs they perform. The rod to piston surface areas are way more than needed. That is one of the reasons that push mower engines have survived on no oil changes at all and when they do get changed, a lot of users simply head down to the dollar store and buy some cheap oil and lo and behold, it works.
Now on something like a gen set that is critical to life and limb, I'd go syn and a bit on the heavy side. such as 15w40 or 5w40 diesel oils like Rotella or Mobil 1.
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Ironically, this past week I hit the 5 hour mark to first oil change on my inverter. I had done 4 hours and got interrupted, so one more under about 50% load, give or take. I forget but I'll say ambient temperature was about freezing. Brought in, did not wait long, and took out my highly calibrated HF laser thermometer. 65F is what it said the oil in the sump was. The pinky test confirmed it. [Champion 2500W invertor, 1800W continuous, 750W load or thereabouts, little 80cc 4 stroke.]

Sample size of one notwithstanding, at least for this engine I'll not worry too much about it. I'll repeat maybe this summer and see how hot it gets. I'm thinking a few 5 hour oil changes for now. Plenty of 5W30 on the shelf, next time I run to the store I'll look into what a 10W30 goes for (one 5qt container is 10 oil changes, which might be 5 years, so why should I worry about cost?).