Generac Oil

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I have a year old Generac 22K. Oil change specs:

1. Change after first 25 hours of operation. (11 hours on it now)

2. Use Generac 5W-30 oil (Service class SJ and SL or better).

Mobil 1 5W-30 is SL, SM, SN. Cost of a 5 qt jug is $26. One qt of Generac oil is $14(!). Both oils are full synthetic.

My concern is voiding the 5-year warranty if I use the wrong oil.

Comments?
 
I have a year old Generac 22K. Oil change specs:

1. Change after first 25 hours of operation. (11 hours on it now)

2. Use Generac 5W-30 oil (Service class SJ and SL or better).

Mobil 1 5W-30 is SL, SM, SN. Cost of a 5 qt jug is $26. One qt of Generac oil is $14(!). Both oils are full synthetic.

My concern is voiding the 5-year warranty if I use the wrong oil.

Comments?

Possibly if they were qualified enough to know. If I had to guess no, the subject would not come up!

I have a whole house standby Generac for over 6 years now and I use Mobile 1 in it (and ever other 4 stroke engine I own.)


Edit Mob1 is a approved oil in my area. Its very common for companies to say that you must use their product to keep warranty so they make more money!. In most cases any premium oil that meats the specifications is also accepted.
 
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I don't know honestly, but if it were me...

I'd spend a few extra dollars and buy the oil they specify. If anything goes awry, they have no out.
 
you're supposed to change oil in those :eek:
Hell, learned something today......My old Generac(bought at LOWES about 20 years ago) got it's first oil change this past spring when I took it to the guy around the corner who works on small engines. Paid $80 to get all the rotted lines changed out, new carb and new oil put in.
Pretty much good to go for the next 20 years :D
As far as warranty-I think it is out by a few months :D
 
I have a Generac 5K. Got it when the Y2K thing was suppose to shut everything down 21 years ago. Its had a steady diet of synthetic oil its entire life. It still starts on the first pull.
 
I purchased a Generac 22 kW generator this year. It has no such requirement to use Generac's oil. Generac specifies full synthetic API SJ, SL or better, SAE 5W-30 for all temperature ranges. They require first change at 25 hours, then every 2 years or 200 hours thereafter. They offer a Generac convenience oil change kit, but my warranty doesn't say it's use is mandatory. The engine is a 999 cc air cooled v-twin, probably good for 30 horsepower, pretty low intensity for a 61 cubic inch engine, especially one that self exercises weekly. Full synthetic makes total sense for an engine that sits around doing nothing. The real worry with these machines is the cheap foreign made electrical and electronic junk they hang on the engine and transfer switch. I've had five load control contactors (relays) and a control power transformer go bad in the space of six months. The engine just keeps purring away loudly, once a week.
 
How could they (the manufacturer) possibly know what oil brand you used, or even if the oil was changed as specified in the manual? I would just use whatever brand of synthetic I could find at the weight they recommend, and change at the interval that is listed in the manual.

They might ask to see the receipts for the oil and filters. Also, there's a maintenance log in the manual that should be kept current. You could fake that, of course.
 
I have a Generac 16kw generator hard wired into the main panel on my house. The house is now 2 years old and I don't believe the oil has ever been changed so I plan on doing it myself before the first snowfall. I bought a few of their brand oil filters and a jug of Castrol Edge full synthetic 5W-30 oil which should be good for a couple of changes. I think the oil was about $26 for 5 qts. It should meet or exceed anything that Generac sells.
 
Have Generac 22KV That was installed late last year. Outside of the weekly test hasn't run long enough to matter. Then came hurricane Delta. From 4am Saturday morning till 8pm Sunday night it never shut off. I'll be calling Generac in the am and order some extra filters. Right now I topped off the generator oil with Castrol 5w-30w full synthetic. Same stuff my truck has been using. House is starting to look like a gas station. Oil for the riding mower, oil for the kubota diesel tractor, oil to be mixed with gas for power tools, like chain saw,weed whacker,blower, tiller. Frank
 
A-37

Glad to see that you have made this posting, just last week we had a 22KW
Generac installed along with their transfer switch.

So your oil / filter questions along with comments that are showing up are
picking my interest.

terry
 
I bought a quart of Generac 5w30 full synthetic at my lawn mower / small engine repair place (they are a Generac dealer) for 5 or 6 bucks.
 
maintain a service log book specifying when and what service was performed, including test runs. As long as it meets the required technical requirements to support the warranty , good to go.
 
Like I mentioned previously had a 22 KW generator last year. Comes on every friday at 5pm, runs for about 5 minutes then shuts down. Called Generac and ordered oil filters,air filters,spark plugs. and the all important 7.5 amp controller fuse. Next will check the transfer switch and see what fuses it takes. Then all this stuff will be stored in an old tool box that has been cleaned up,repainted and labeled as to the contents. I am not fond of hunting down stuff in the dark or early hours way before I have to get up. Frank
 
somewhere in the lower dank levels of my memory there is some sort of federal ruling that allows you to use other oils made to the same SAE ASTM requirements. if generac says use SAE 5w30 then any brand 5w30 will not void your warranty. kind of like using winchester ammo in your remington. its all made to saami spects
 
I don't have a Generac as the newer ones have a very poor reputation.

I do have a Briggs and Stratton whole house generator. I also have an annual service contract because I don't want to play around with it. I want that MoFo to start up any time the power goes out.

Of course, by buying a whole house generator, I've pretty much guaranteed that power will never go out again.
 
About those filters..................way back in the last century I bought my first Subaru. Dunno if they still do, but back then they had monthly new owner coffee klatches to pass on information (and make sales pitches). One of their exhibits was sectioned oil filters by Subaru, Fram and someone else. The Subaru filter had vastly more filter material than either of the after market versions, plus a bypass valve in case it got clogged. Worth the extra coin.


Gent I worked with was a fellow diesel owner and did the same thing on various filters for the 7.3 IH/Ford engine. The Fleetguard and Wix filters had substantially more filter material than the "other" brands.

So, to riff on the old NAPA jingo, all filters ain't necessarily the same.

BTW, on the issue of periodic running.....the idea is to not only run the engine, but the generator should be run at about 1/2 load to keep the actual alternator/generator windings moisture free. I worked at a site with 4 standby generators (total output 1.2 Megawatts) that were supposed to go from hot standby to full load in 10 seconds. Both the engines and the generator units had heaters to keep them at operating temperature and oil pressure was maintained at proper levels too. Despite that, each unit had a mandated hot run under load once a month.
 
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Any of you folks ever seen any 24 hour no load fuel usage figures on the whole house generators and small gas engines? All I have ever seen posted is about 25% load. Average home usage is about 32kwh. A 1.5 kw could generate 36kwh in 24 hours.
 
you're supposed to change oil in those :eek:
Hell, learned something today......My old Generac(bought at LOWES about 20 years ago) got it's first oil change this past spring when I took it to the guy around the corner who works on small engines. Paid $80 to get all the rotted lines changed out, new carb and new oil put in.
Pretty much good to go for the next 20 years :D
As far as warranty-I think it is out by a few months :D

I've got some off brand Job Boss maybe generator that I had the same gas in it for 8 years. Just regular pump gas too.

I never needed it, but would start it up every couple months and let it run about 15 minutes, then shut the gas off and let it run out. Always started on the second pull.

Couple years ago I changed the oil, and drained out the gas. Cleaned the carb good, added around 16OZ of fresh gas to it and let it run till it ran out.

Rolled it back in the shed. Probably won't ever start now that I did that.

The gas I drained out in the lot next door smelled like varnish and didn't even kill the grass. Yeah I know that's a bad thing to do, but it was just one time.
 
If you can get it started, that is. If you can find gas for it.

A friend of mine down in Louisiana had to run his portable generator for over three weeks after Laura came through.

It cost him about $50.00/day for gas and he had to drive around looking for it.

The other advantages to a whole house generator is that it's permanently connected to the electrical system and will start automatically. It will also trip the transfer switch. You also don't have to lug it through the snow if you lose power.

Did I mention it's much easier to steal a portable generator?

The amount of power generated versus used is only one minor consideration.

Any of you folks ever seen any 24 hour no load fuel usage figures on the whole house generators and small gas engines? All I have ever seen posted is about 25% load. Average home usage is about 32kwh. A 1.5 kw could generate 36kwh in 24 hours.
 
Like I mentioned previously had a 22 KW generator last year. Comes on every friday at 5pm, runs for about 5 minutes then shuts down.

much better to have it run for at least 15 mins after the unit comes up to full operating temperature to burn off all condensates. In my facilities career managed dozens of gensets from small to max, when another facility was rolled into the portfolio I managed would have our genset techs perform a full service including oil sample to the lab. Gensets that were excercised routinely for longer periods always had a better oil test than newer units run shorter. So 30 mins was our standard.
 
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