Oil recommendation for Generac 20kw generator

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I just had a Generac model 5875 standby generator installed at my house. The engine is a 999cc, air cooled, V twin.

The manufacturers OIC is 200 hours, and the following recommendation are made in the owners manual: above 32 deg F, SAE 30; between 40 deg F and -10 deg F, 10W30; 10 def F and below, synthetic 5W30.

This reminds me of lawn mower engine recommendations of thirty years ago. Pwhy a need for straight 30 weight. I would like to use Pennzoil Ultra 5W30, like I do in all my motor vehicles. I would think this would be much better for the engine.

Am I missing anything?
 
Originally Posted By: **** '97FLHRI
I just had a Generac model 5875 standby generator installed at my house. The engine is a 999cc, air cooled, V twin.

Air cooled engine: Rotella 10W-30 semi-syn or Rotella Full Syn 5w-40. (The 5w-40 would be a good all season oil). All are HDEO and availalble at Walmart in gallon jugs.

Don't use weak passenger car oils in air cooled power equipment.

Lawn mowers run for a couple of hours at a time. A generator, especially a permanent stand-by unit, could run non-stop for days.
 
I've got 5 generators,6000 watts each. I've also got 12 5.5 hp Honda powered air compressors. I can tell you from experience that fuel dilution is a real issue with mine and an hdeo is a good idea,unless you are planning short oil change intervals.
In the summer I use rotella 15w-40. Winter I use a cheap 5w-30 and change it every 2 weeks. At 2 week intervals there is more oil in the crankcase then when I started and smells very strongly of gasoline. I suspect the straight grade recommendation is due to this.
 
Originally Posted By: **** '97FLHRI
I just had a Generac model 5875 standby generator installed at my house. The engine is a 999cc, air cooled, V twin.

The manufacturers OIC is 200 hours, and the following recommendation are made in the owners manual: above 32 deg F, SAE 30; between 40 deg F and -10 deg F, 10W30; 10 def F and below, synthetic 5W30.

This reminds me of lawn mower engine recommendations of thirty years ago. Pwhy a need for straight 30 weight. I would like to use Pennzoil Ultra 5W30, like I do in all my motor vehicles. I would think this would be much better for the engine.

Am I missing anything?


Amsoil makes a couple oils that are 10W-30/SAE 30. The beauty is no viscosity index improvers. More "room" in solution for oil, additives including rust inhibitors. I run the inexpensive Amsoil ACD 10W-30/SAE 30 in my generator. It's been in there 3 years now. I just replaced the cheapo supplied battery and it cranks up really nicely.

Amsoil ACD

Amsoil ASE
 
A friend is a Generac tech, and when he went to their school they reccomended M1 5-30. When he performs PMs this is what he puts in. If there hasn't been a long power failure run, and only the weekly start up is done, then he changes it every two years for his customers.
 
This is an application where I think Amsoil has the best solution. The ACD is what I would use here.
 
Originally Posted By: tig1
A friend is a Generac tech, and when he went to their school they reccomended M1 5-30. When he performs PMs this is what he puts in. If there hasn't been a long power failure run, and only the weekly start up is done, then he changes it every two years for his customers.






Mobil 1 5W30 is only a "weak" recommendation in my experience. This is ONLY because it is commonly available. The 992cc, air cooled, Generac I owned consumed it faster than other oils in a power outage of over 48 hours. A few other owners will vouch for this. At which point, the generator will shut itself off, due to a low oil level. It is only a passenger car oil.

The Rotella 10W30 and Amsoil recommendations last much longer in this application. Even a 5W40 is a better choice.
 
Originally Posted By: Best F100
Originally Posted By: tig1
A friend is a Generac tech, and when he went to their school they reccomended M1 5-30. When he performs PMs this is what he puts in. If there hasn't been a long power failure run, and only the weekly start up is done, then he changes it every two years for his customers.







Mobil 1 5W30 is only a "weak" recommendation in my experience. This is ONLY because it is commonly available. The 992cc, air cooled, Generac I owned consumed it faster than other oils in a power outage of over 48 hours. A few other owners will vouch for this. At which point, the generator will shut itself off, due to a low oil level. It is only a passenger car oil.

The Rotella 10W30 and Amsoil recommendations last much longer in this application. Even a 5W40 is a better choice.


M1 0w40 is my personal choice, as it is incredibly durable and doesn't seem to consume.
 
Originally Posted By: Best F100
Originally Posted By: tig1
A friend is a Generac tech, and when he went to their school they reccomended M1 5-30. When he performs PMs this is what he puts in. If there hasn't been a long power failure run, and only the weekly start up is done, then he changes it every two years for his customers.






Mobil 1 5W30 is only a "weak" recommendation in my experience. This is ONLY because it is commonly available. The 992cc, air cooled, Generac I owned consumed it faster than other oils in a power outage of over 48 hours. A few other owners will vouch for this. At which point, the generator will shut itself off, due to a low oil level. It is only a passenger car oil.

The Rotella 10W30 and Amsoil recommendations last much longer in this application. Even a 5W40 is a better choice.



M1 5-30 is far from "weak". It does have the Honda HTO-06 spec which is a high heat low deposite turbo spec. My friend, the Generac tech, has had experience just the opposite of yours and and those you speak of. Even my daughter has a 17KW Generac and has several long runs of nearly a week with M1 5-30. No unusual oil useage. My tech friend has upwards of 40 customers he services with M1 5-30 and he reports no high oil consumption that he notices when he does his PMs.
 
Originally Posted By: tig1
Originally Posted By: Best F100
Originally Posted By: tig1
A friend is a Generac tech, and when he went to their school they reccomended M1 5-30. When he performs PMs this is what he puts in. If there hasn't been a long power failure run, and only the weekly start up is done, then he changes it every two years for his customers.






Mobil 1 5W30 is only a "weak" recommendation in my experience. This is ONLY because it is commonly available. The 992cc, air cooled, Generac I owned consumed it faster than other oils in a power outage of over 48 hours. A few other owners will vouch for this. At which point, the generator will shut itself off, due to a low oil level. It is only a passenger car oil.

The Rotella 10W30 and Amsoil recommendations last much longer in this application. Even a 5W40 is a better choice.



M1 5-30 is far from "weak". It does have the Honda HTO-06 spec which is a high heat low deposite turbo spec. My friend, the Generac tech, has had experience just the opposite of yours and and those you speak of. Even my daughter has a 17KW Generac and has several long runs of nearly a week with M1 5-30. No unusual oil useage. My tech friend has upwards of 40 customers he services with M1 5-30 and he reports no high oil consumption that he notices when he does his PMs.





I meant no offense when I used the term weak. "Weak" is relative. However, my point is there are better choices available, even in the ExxonMobil lineup. In the application Mobil 1 5W30 is used (liquid cooled engines), engine temperatures are not that demanding. Take the Honda HT0 - 06 specs, for example> engine temperatures are not out of the norm for a liquid cooled engine. So as a result, engine deposits would not be a concern on a generator. Generac techs are told to "toe the company generic 5W30 synthetic recommendation line." That's what my Generac tech said, who came to my house.

If you reside in a state like Arizona, Florida or Louisiana, and have a hot, AIR cooled generator running for weeks at a time in the summertime, you can do better than Mobil 1 5W30. If you wanted to stay with ExxonMobil, their 10W40 Motorcycle oil or their Delvac 5W40 would be still be working a lot longer. Who can argue that their applications are less demanding than what Mobil 1 5W30 was designed for? When your oil capacity is only 2 qts, why not pay a few extra bucks for better performance? The original question was asked from the state of NJ. Many folks who lost their power from Hurricane Sandy last year in NJ were without power for over a week. Those generators ran a lot hotter than our low oil temperatured, cars with Mobil 1 5W30.

So I still stand by my answer.
 
Best F100,
No offence taken. So with Generac gens you feel thicker is better? Or doesn't use as much oil over a long period of time. Apparently Generac doesn't agree with thicker is better as far a engine wear and overal performance is concerned. Generac has done extensive testing with various oils and weights and their conclusion is 5-30 is best overall for their equiptment. Now if your argument is thicker may use a fraction less oil than 5-30, then you may have a valid point. But with long gen runs in extreme heat as we have here in Illinois in the summer(much hotter than Florida)Generac techs here perfer M1 5-30.
 
Originally Posted By: tig1
Best F100,
No offence taken. So with Generac gens you feel thicker is better? Or doesn't use as much oil over a long period of time. Apparently Generac doesn't agree with thicker is better as far a engine wear and overal performance is concerned. Generac has done extensive testing with various oils and weights and their conclusion is 5-30 is best overall for their equiptment. Now if your argument is thicker may use a fraction less oil than 5-30, then you may have a valid point. But with long gen runs in extreme heat as we have here in Illinois in the summer(much hotter than Florida)Generac techs here perfer M1 5-30.




I can't say in 100% of the cases that thicker is better. However, if you think about it, you are NEVER going to see generator company specifying a motorcycle spec oil, or a Delvac 5W40 - just because most owners won't go to the effort to find it. The average person will just grab the first car oil 5w30 they see, and use it in a generator.

I believe the Bitoger Cujet in Florida, talked about the number of generator failures all around him during one of the most recent hurricanes a couple of years ago. Those owners were using various car oil 5W30s during extended power outages in their air cooled generators. He used Mobil 1 15W50 in his, and had no issues. You think a manufacturer is going to recommend 15W50? I don't. But the results speak for themselves.

I saw somewhere that Generac claims they have the longest rated hours of all 3,600 rpm air cooled generators - which is 3,000 hours. This is good. Keep in mind, that these engines can not be rebuilt after 3,000 hours. You have to buy a new one. If you you pony up and buy a more expensive, 1800 rpm, liquid cooled, air cooled engine, you can double that figure. Most diesel generators that I have seen, start out around a 10,000 rating. I have heard of a number of owners getting over 20,000 hours of these. Note that diesel generators, which are used by a number of contractors and on constuction sites all use either 15W40 or 5W40. Go figure.
 
I have a Generac 17k portable with 200 hrs and been using M1 HM 10w30 syn yr-round here in the deep south. But would Generac syn 10w30 be any better at all? Would a straight 30w be better for the high heat here?
 
Originally Posted by Ricky_Samsonia
I have a Generac 17k portable with 200 hrs and been using M1 HM 10w30 syn yr-round here in the deep south. But would Generac syn 10w30 be any better at all? Would a straight 30w be better for the high heat here?


You're fine with the M1 10w-30 just monitor for oil consumption and change the oil every 100 hours or 6 months. If it's consuming oil go to synthetic SAE 30.
 
Originally Posted by **** '97FLHRI
I just had a Generac model 5875 standby generator installed at my house. The engine is a 999cc, air cooled, V twin.

The manufacturers OIC is 200 hours, and the following recommendation are made in the owners manual: above 32 deg F, SAE 30; between 40 deg F and -10 deg F, 10W30; 10 def F and below, synthetic 5W30.

This reminds me of lawn mower engine recommendations of thirty years ago. Pwhy a need for straight 30 weight. I would like to use Pennzoil Ultra 5W30, like I do in all my motor vehicles. I would think this would be much better for the engine.

Am I missing anything?

Oil selection for CNG/LNG engines is complicated. CNG/LNG engines suffer from valve recession as well as excess oil temperatures. The following article explains the lubrication challenges of a CNG/LNG engine.

Oils for natural gas engines -- Society of Tribologists and Lubrication Engineers (STLE)

This guy says don't run thinner oils such as ILSAC 5W-30 (same thing with an ILSAC 10W-30) because they get consumed a lot. This rules out the Pennzoil Ultra 5W-30:

https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/1771883/re-generac-generator#Post1771883


I would say perhaps stick with the recommended SAE 30. If not, a 15W-40 HDEO is the closest thing to a SAE 30. If not, run a 5W-40 (Delo, Rotella, etc.) or a 0W-40 (Belgian/German Castrol or M1 FS). Perhaps you can also find out what the ideal oil SA (sulphated ash) for this engine is and then choose the oil with the right SA.
 
If you have a question please start a new topic. Dredging up a 7 year old topic to ask a question isn't helpful to anyone.
 
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