20wt for low load on small inverter generator at or below 0f?

[spasm3]

So, let’s put some (completely made up) numbers to this.

Here is a list of the viscosities recommended by Champion. Yes, I’m aware 0w-20 isn’t on this list. lol

View attachment 197923

So, with that in mind, let’s take my report earlier of an oil temp of 195f (90C) at 103f ambient temp with a 50% load. I think it’s reasonable to say I had the engine warmed up but not too hot, even in that kind of ambient heat.

If champion says I can use a 30 or 40wt oil at those temps we can graph the viscosity of those oils and get an approx viscosity range to stay between.

I used the Widman calculator (does he still come around here?), and inputted some M1 flavors and their respective 40c and 100c viscosities.

M1 AFE 0w-16 (because I live on the wild side)
M1 EP 5w-20 (have this in the garage)
M1 EP 5w-30
M1 FS 5w-40

From what I see, the 30 and 40wt oils have a viscosity of 12.65 and 16.59cSt respectively at 90C. So let’s shoot for a range of 12 to 17. It may very well be ok to use a wider viscosity range, but for now let’s stick with this.


View attachment 197922

At 25% load and low ambient temps, I’m anticipating an oil temp of 140f (60C) max. But, very likely less than that based on DNewton3’s reports above.

At that temp, every oil listed (even the 0w-16) is outside of my haphazardly chosen viscosity range of 12-17cSt (although probably not to any catastrophic consequence).

To end this madness, I’ll just say I’m doing some testing the first night it gets cold, and will report back with my findings.

To much thinking about it. Put oil in it and run it. If it has a low oil level switch it may trip even with a light weight oil. Run it on idle till it warms a little then go.

I think in cold weather its ok, i just don't see any advantage to doing it. You are in Texas, you may see single digit temps. IF you don't need the genset, youll have to dump it in the summer.
I put oil in mine and it may sit a year or 2 ( i crank it every 3 months and run it) but its ready to go whether its 10f or 100f. I use a stout, high TBN 5w30 and forget about it.

 

[jhellwig]

As i have said time and time again on here, use something close to the recommended oil, keep it at the proper level, change it every now and then and something else will die or you will get tired of using long before it wears out due to the oil you used. And yes I know what Cujet says. If you hammer any engine in those conditions you are going to ruin something unless you are on top of it all the time.

 

[oil pan 4]

If you knew the oil wasnever going to get hotter than about 85c a 20wt oil would be fine.
Your best bet for a lightly used generator in the cold is probably a sj rated 0w-30 or 5w-30. You will have far better luck finding a sh or sj rated 5w-30 oil than a 0w-30.

 

[oil pan 4]

So, let’s put some (completely made up) numbers to this.

Here is a list of the viscosities recommended by Champion. Yes, I’m aware 0w-20 isn’t on this list. lol

View attachment 197923

So, with that in mind, let’s take my report earlier of an oil temp of 195f (90C) at 103f ambient temp with a 50% load. I think it’s reasonable to say I had the engine warmed up but not too hot, even in that kind of ambient heat.

If champion says I can use a 30 or 40wt oil at those temps we can graph the viscosity of those oils and get an approx viscosity range to stay between.

I used the Widman calculator (does he still come around here?), and inputted some M1 flavors and their respective 40c and 100c viscosities.

M1 AFE 0w-16 (because I live on the wild side)
M1 EP 5w-20 (have this in the garage)
M1 EP 5w-30
M1 FS 5w-40

From what I see, the 30 and 40wt oils have a viscosity of 12.65 and 16.59cSt respectively at 90C. So let’s shoot for a range of 12 to 17. It may very well be ok to use a wider viscosity range, but for now let’s stick with this.


View attachment 197922

At 25% load and low ambient temps, I’m anticipating an oil temp of 140f (60C) max. But, very likely less than that based on DNewton3’s reports above.

At that temp, every oil listed (even the 0w-16) is outside of my haphazardly chosen viscosity range of 12-17cSt (although probably not to any catastrophic consequence).

To end this madness, I’ll just say I’m doing some testing the first night it gets cold, and will report back with my findings.

Science!
I thought 10.5cSt at operating temperature was the recommended minimum.
Although my pressure washer engine that runs wot, 4,000rpm, 260F oil temperature with 20w-50 oil gives me a few more RPMs when I open the oil cooler and cool the oil down to about 220f. Which would put that 50wt oil closer to the 17cSt range.

 

[Rogueman2016s]

Getting ready for the colder weather next week. Expecting to see around 0f or a few degrees lower than that.

I have a 2000w (1700w running) Champion Inverter generator. For my use, it’ll probably average between 200-300 watts continuous.

-100w for my fireplace insert fan
-100w for fridge (Seems low. But, this is what I measured with a Kill-A-Watt while the compressor was running)
-And around 100w for TV, a few lamps, charging phones, etc.

Since it’ll basically be sitting on idle all of that time, will this little air cooled engine heat the oil up enough? Or would it be beneficial to drop it down to a lower viscosity?

I'd personally use a 10w30 or a 5w30 full synthetic.

 

[dnewton3]

Mitsuman47 -

Given the following:
- you expect temps in single digits, if not lower
- your owner's manual states "5w-30 synthetic" is appropriate for a very wide range of temps
I think the choice is obvious; 5w-30 grp IV or V.

However, you do state you already have some 5w-20 Mobil 1 EP in your garage. So is your dilemma whether to buy a quart of 5w-30, versus use what you already have? Presuming you're the typical BITOGer, you don't mind an OCI or two. If you're trying to avoid a trip to the store for a quart of 5w-30, I'd say the 5w-20 EP would do just fine for the short term concerns. Then you can OCI it back to a 5w-30 this spring, and leave that in year round.

* 5w-30 would be the "best" choice
* 5w-20 will be a "good" alternative for the uber-cold short term concerns this season

 

[cptbarkey]

Changing tactics a little, the Champion 2500 will be going to my Mom's ranch tomorrow in case she needs it. Picked up another bigger Predator. Northern Tools was cleared out, Home Depot etc.

Didnt have any 10w30 on hand, but kinda sorta made 1.5W30 mixing Total Quartz with a 5 hour break in currently in progress. Thank you for the help and advice. @dnewton3

 

[mitsuman47]

Mitsuman47 -

Given the following:
- you expect temps in single digits, if not lower
- your owner's manual states "5w-30 synthetic" is appropriate for a very wide range of temps
I think the choice is obvious; 5w-30 grp IV or V.

However, you do state you already have some 5w-20 Mobil 1 EP in your garage. So is your dilemma whether to buy a quart of 5w-30, versus use what you already have? Presuming you're the typical BITOGer, you don't mind an OCI or two. If you're trying to avoid a trip to the store for a quart of 5w-30, I'd say the 5w-20 EP would do just fine for the short term concerns. Then you can OCI it back to a 5w-30 this spring, and leave that in year round.

* 5w-30 would be the "best" choice
* 5w-20 will be a "good" alternative for the uber-cold short term concerns this season

I’m not concerned with the money, or time. I created this thread to see what the hive thinks about cold weather and air cooled engines. I know how I come to my conclusions, but wanted to see others rationale for their choices in these conditions.

I actually have some Motul X-Clean+ 5w-30 on hand. However, it’s an ACEA C3 mid-saps oil. So, not sure if that would provide the protection needed for this type of engine. It does happen to be Porsche C30 approved, so how bad can it be?

 

[oil pan 4]

Has anyone been able to find a 20wt oil that's sh or sj rated and appropriate for a flat tappet air cooled carburetor motor?
I find synthetic, conventional and blend sj rated 5w-30 oil all the time for "lawn mowers" and "power equipment".

 

[Astro_Guy]

Has anyone been able to find a 20wt oil that's sh or sj rated and appropriate for a flat tappet air cooled carburetor motor?
I find synthetic, conventional and blend sj rated 5w-30 oil all the time for "lawn mowers" and "power equipment".

I don't think SAE xw-20 was common here in the US back in the days of API Service SJ. IIRC new Hondas and Fords called for 5w-20 back in 2005.

 

[oil pan 4]

I don't think SAE xw-20 was common here in the US back in the days of API Service SJ. IIRC new Hondas and Fords called for 5w-20 back in 2005.

So if anyone finds any it will be in a museum.

 

[mitsuman47]

Reporting back, as promised. Only got down to 18f this morning. I used some incandescent light bulbs and mocked up a typical overnight 300w load for my winter time use. (Fireplace insert fan, fridge, and freezer will be in use while folks are sleeping). All wattages verified with Kill-A-Watt meter. Generator was stored in my 65f garage prior to the test. Idled for 5 minutes before I added load to the engine.

After 30 minutes on eco mode with 300w load the oil temp stabilized at 108f. I used both a k-type thermocouple and digital probe thermometer.

Based on this, I have no problem running the 5w-20 I have in the sump. Especially since it was a balmy 18f. I doubt the oil temp would break 100f if it were 0f outside.

 

[dlundblad]

Did you need the generator yet?

 

[mitsuman47]

Nope. Bought my first generator in 2017 after our town got hit by 3 tornadoes in one day. Since owning them (I have 3 now), my electric service hasn’t as much as flickered.

I was actually one of the lucky ones that made it through the 2021 winter storm without losing power.

I think the stability of your utility services is directly proportional to the amount of money you’ve spent to live comfortably without them.

 

[oil pan 4]

You could leave the generator with no oil in it and no gas in it.
But leave a quart of 5w-20 and a quart of summer oil sitting on it along with a note on the pull handle to fill/check the oil before starting.
That way if you don't need it till summer time just put your SAEsummerweight oil in it when it's warmer.

 

[dnewton3]

Reporting back, as promised. Only got down to 18f this morning. I used some incandescent light bulbs and mocked up a typical overnight 300w load for my winter time use. (Fireplace insert fan, fridge, and freezer will be in use while folks are sleeping). All wattages verified with Kill-A-Watt meter. Generator was stored in my 65f garage prior to the test. Idled for 5 minutes before I added load to the engine.

After 30 minutes on eco mode with 300w load the oil temp stabilized at 108f. I used both a k-type thermocouple and digital probe thermometer.

Based on this, I have no problem running the 5w-20 I have in the sump. Especially since it was a balmy 18f. I doubt the oil temp would break 100f if it were 0f outside.

Thanks for the feedback! Good information.

That aligns with my experiences from several years back. The crankcase and oil never get anywhere near full temp during ambient cold snaps. As I said, when it was -17F during my three-day event, my genny crankcase was barely warm to the touch after days of running.

Imagine if you had that genny stored outside rather than in your garage. The oil would have been much thicker at start-up. It still would have come up to the same temp eventually, but that oil would have been much more viscous had it been sitting at 18F prior to the start. You need the oil to be able to "splash", and therefore the oil has to be thin enough to be picked up by the dipper on the con-rod and slung about, in these little air-cooled engines.


Without any doubt, if one suspects really cold temps (around 0F or below), you'd better have a fairly thin lube in the engine.

 

[dnewton3]

You could leave the generator with no oil in it and no gas in it.
But leave a quart of 5w-20 and a quart of summer oil sitting on it along with a note on the pull handle to fill/check the oil before starting.
That way if you don't need it till summer time just put your SAEsummerweight oil in it when it's warmer.

The problem with this approach is that you still need to run the genny a few times during the year, under load. It's a very good idea to exercise the electrical powerhead in generators, or they can lose their field strength over long periods of dormancy; so much so that they won't produce power unless the field is manually excited. Leaving oil out, and therefore not starting the engine until you need the genny after several years, assures that some day that unit won't produce electrical power, despite the engine being perfectly fine.

 

[Astro14]

The problem with this approach is that you still need to run the genny a few times during the year. It's a very good idea to exercise the electrical powerhead in generators, or they can lose their field strength over long periods of dormancy; so much so that they won't produce power unless the field is manually excited. Leaving oil out, and therefore not starting the engine until you "need" the genny after several years, assures that some day that unit won't produce electrical power, despite the engine being perfectly fine.

Every big automatic generator I looked at does a monthly “self test” where it starts and runs. I reckon that running bit is important, or it wouldn’t be programmed to do so.

Some of them charge their starting battery while doing so, and for some, there is a battery maintainer option.

Curiously, they all specified one oil viscosity, no temperature consideration.

 

[kschachn]

Every big automatic generator I looked at does a monthly “self test” where it starts and runs. I reckon that running bit is important, or it wouldn’t be programmed to do so.

Some of them charge their starting battery while doing so, and for some, there is a battery maintainer option.

Curiously, they all specified one oil viscosity, no temperature consideration.

Yes ours does that but it only exercises the engine not the generator. Once I had a problem just as dnewton3 describes, it would not produce electricity but would otherwise run normally. After several restarts it appeared to correct itself so now I manually run it under load now and then. That's been a few years ago and the non-generation problem has not recurred, who knows what was happening exactly but I... feel better... about seeing it operate under load.

As an aside no way on earth I would use a 20-grade oil in a generator. I'm not running out there in the summer to change oil (assuming I'd even be home at the time) to change to something thicker. I run 0W-40 in it year round.

 

[mitsuman47]

You could leave the generator with no oil in it and no gas in it.
But leave a quart of 5w-20 and a quart of summer oil sitting on it along with a note on the pull handle to fill/check the oil before starting.
That way if you don't need it till summer time just put your SAEsummerweight oil in it when it's warmer.

I’ll leave the 5w20 in there for now. I’ve decided this will be my cold weather generator. See my comment above about preparing for loss of public utilities. I think I’ve secured stable electric service for my whole county. They can thank me later.

Thickies stop reading now. You’ve been warned.

I might even try to source some 0w12. The viscosity of that oil would allow me to run it up to around 155f oil temp, where it would be the viscosity of a 5w30 at 195f. Yet, down around 40c where I’ll likely see oil temps in a winter outage, the viscosity is still higher than ideal viscosity at normal operating temp with a 5w-30. And, if I happen to observe the oil temp rising too high, it takes 5 minutes to change the oil in this thing.

I rigged up a dipstick that has a k-type thermocouple in it, so I can measure oil temps in real time. I’ll report back on that when I get pictures and data from it.

Edit: I should add that I have two other generators as well. So, if I happen to grendade this one (doubtful), oh well, lesson learned. I’ll crank one of the other ones.