Synthetic 10W30, HDEO 5W40 or Straight 30 wt oil?

[Best F100]

Picture this:

Three identical AIR cooled generators are lined up side by side. A Florida hurricane has hit and the power will not be restored anytime soon in 95F+ temperatures. All three generators are running nonstop for their respective residences with the same power load on them. The owners manual recommends a 10W30 synthetic or straight 30 wt.

Generator A) Has in it, a 10W30 synthetic, like a Mobil 1. Generator B) Has in it a 5W40 HDEO oil, like a Rotella or Delvac 1. Generator C) Has in it a straight 30 wt oil, like a Rotella or Delo - like many landscapers and contractors use in their air cooled equipment.

Question class: Which of the three generators will be the "last man standing". By that, I mean which of the three will NOT stop running, (from consuming all of its oil capacity) or from engine engine failure? For extra credit, give your reasons why you are so sure.

Full disclosure: I own a big, 8,000 watt/10,000 peak, 14 HP, air cooled, Rigid Brand generator with a Subaru engine. Gasoline fuel. 3600 rpm. Oil capacity 2 quarts. It is on a nice "hand dolly" platform on wheels with a roll cage surrounding it. Roll it into place and repower the whole house. I have had it for 3 years now. I know air cooled engines aren't rated anywhere near the hours, the liquid cooled, 1800 rpm generators are, but we owners try to get the most out of them. I am using up the last of my Mobil 1, and will be using (I think), the Delo 15W30 Severe Duty HDEO in this application that I bought for about $12 gallon on sale.

 

[Ramblejam]

Paging Cujet...

 

[AirgunSavant]

10w30 with one receptacle with a big fan plugged into it blowing over the motor

 

[901Memphis]

Whichever one is running Mobil 1 High Mileage 10w40

 

[FastLane]

If it's a quality engine, it won't matter. The generator side will probably fail before the engine. I would go 10W30 Mobil 1 myself.

The Honda and Briggs powered generators go for a long time with out issues. It's the Chinese stuff that you have to worry about.

 

[Powerstroke]

Amsoil ACD 10W30/30 or Mobil 1 10w30.

 

[beanoil]

In your scenario, the straight 30 weight. No VII to shear and thin the oil, the HD diesel oil will handle whatever soot and dirt is present, and a straight weight shines in extreme heat.

 

[gfh77665]

Straight 30.

 

[dlundblad]

If the OM says to change it every 50 hrs, change it at 50 hrs. Don't run whatever feels good and hope for the best.

If one lived in an area like OP's scenario, a stash of oil would be handy to have for possible long periods of power outages.

 

[eljefino]

Originally Posted By: dlundblad
If the OM says to change it every 50 hrs, change it at 50 hrs. Don't run whatever feels good and hope for the best.

If one lived in an area like OP's scenario, a stash of oil would be handy to have for possible long periods of power outages.


How much gasoline does one go through in 50 hours? That's where the stash lays.

Oil still works a decade later, and gasoline spoils significantly faster.

I can tap my fuel-injected cars for fuel at the rail... and anyone who lives near drama (everybody) should pick up this skill and practice it when the internet etc still works.

 

[henni]

Is the oil new in all 3 ?

Any oil will work fine provided the conditions otherwise are identical (outdoor ambient temp, shade, ventilation, fuel grade and quality, overall quality of components such as wires, metal, plastic, rubber, spark plug).

I would not run any of your 3 choices, instead an Inverter with ability to throttle down to 2200 RPM or below when demand allows it, plus maintain a pure and clean 121v or 242v feed at 60Hz.

 

[Best F100]

Originally Posted By: henni
Is the oil new in all 3 ?

Any oil will work fine provided the conditions otherwise are identical (outdoor ambient temp, shade, ventilation, fuel grade and quality, overall quality of components such as wires, metal, plastic, rubber, spark plug).

I would not run any of your 3 choices, instead an Inverter with ability to throttle down to 2200 RPM or below when demand allows it, plus maintain a pure and clean 121v or 242v feed at 60Hz.




New oil. These type generators can result in oil temperatures of up to 100F hotter than your typical passenger car. That is my reason for posing the question.

However, I disagree with your "any oil will work fine" statement. I am aware of some air cooled, standby Generac owners who had their units cut off - because of low oil levels before 36 hours of continuous operation in 90F+ temperatures during an outage. At the time, I had a Generac 15K unit. Like the others, I was using Mobil 1 5W30. I burned through most of my 1.75 qt of oil in a 24 hour outage. I went on to use Red Line 5W30 without any issues. That was 6+ years ago, and I am sure formulations have improved.

By the way, show me an inverter generator that can A) repower most items in a typical household - not a campsite and B) is affordable by the average homeowner. While you are at it, show us photos of what yours looks like.

 

[CT8]

Which ever one has its oil level checked and is properly serviced. I would wager that some one buys the generator and runs it until the oil runs out or never changes the oil just adds.

 

[dlundblad]

Originally Posted By: eljefino
Originally Posted By: dlundblad
If the OM says to change it every 50 hrs, change it at 50 hrs. Don't run whatever feels good and hope for the best.

If one lived in an area like OP's scenario, a stash of oil would be handy to have for possible long periods of power outages.


How much gasoline does one go through in 50 hours? That's where the stash lays.

Oil still works a decade later, and gasoline spoils significantly faster.

I can tap my fuel-injected cars for fuel at the rail... and anyone who lives near drama (everybody) should pick up this skill and practice it when the internet etc still works.


I am sure it is a decent amount of fuel. In the event of a storm, it might not be a bad idea to have some 5 gallon cans on hand.

I was suggesting an oil stash so generator's oil could be changed out according to the OM.

 

[jeepman3071]

If they are all similar condition, engine, etc, then the one with the HDEO. If HDEO can stand up to the pressures of diesel engines it will stand up to the heat of air cooled gas engines. I've been running HDEO in all of my OPE and customers OPE for a few years now.

 

[Panzerman]

I use 15w40 HDEO in my generators. Alot of people on here have way to much trust in multi weight car oils. I went out at night and saw the muffler glowing orange. Although the fan of the recoil blows air on them. They get plenty hot. The only time a multi weight car oil matters is at start up. Usually a generator is started and let run at a pretty constant speed. I would use a straight 30HD or 15W40. Both are tough oils. I would not see the reason to use a 5W30,10W30 or even 10W40 oil in a generator in Florida.

 

[4WD]

Anyone running Royal Purple SAE30 in gens ?
SAE30 in synthetic ... No ground up rubber ?

 

[tig1]

Originally Posted By: Panzerman
I use 15w40 HDEO in my generators. Alot of people on here have way to much trust in multi weight car oils. I went out at night and saw the muffler glowing orange. Although the fan of the recoil blows air on them. They get plenty hot. The only time a multi weight car oil matters is at start up. Usually a generator is started and let run at a pretty constant speed. I would use a straight 30HD or 15W40. Both are tough oils. I would not see the reason to use a 5W30,10W30 or even 10W40 oil in a generator in Florida.


Why do you use a multi wt oil then?

 

[tig1]

Originally Posted By: Best F100
Originally Posted By: henni
Is the oil new in all 3 ?

Any oil will work fine provided the conditions otherwise are identical (outdoor ambient temp, shade, ventilation, fuel grade and quality, overall quality of components such as wires, metal, plastic, rubber, spark plug).

I would not run any of your 3 choices, instead an Inverter with ability to throttle down to 2200 RPM or below when demand allows it, plus maintain a pure and clean 121v or 242v feed at 60Hz.




New oil. These type generators can result in oil temperatures of up to 100F hotter than your typical passenger car. That is my reason for posing the question.

However, I disagree with your "any oil will work fine" statement. I am aware of some air cooled, standby Generac owners who had their units cut off - because of low oil levels before 36 hours of continuous operation in 90F+ temperatures during an outage. At the time, I had a Generac 15K unit. Like the others, I was using Mobil 1 5W30. I burned through most of my 1.75 qt of oil in a 24 hour outage. I went on to use Red Line 5W30 without any issues. That was 6+ years ago, and I am sure formulations have improved.

By the way, show me an inverter generator that can A) repower most items in a typical household - not a campsite and B) is affordable by the average homeowner. While you are at it, show us photos of what yours looks like.


A friend is a Gererac service tech and uses only M1 5-30 in all of his PM checks. Many have had long runs and none have had your experience.

 

[lars11]

Or move to Luleå, Sweden. Last major (longer than 3hrs) power outage was in 1979. That's why facebook built their first/only server site in europe there. Also cheap electricity.
Or Stockholm, lived in our house for 13 yrs, no power outage at all.
Maybe luck, maybe no hurricanes, but could also be good engineering, all local lines buried etc...

But the question: The sae 30 HDEO best, the 5w40 HDEO second. could be a tie, due to the multi starting higher but the 30 might be less finicky.