Does oil really go bad after 1 year if it was previously opened?

[eljefino]

You should also put about a 50% load on it when you exercise it.

 

[Ang]

You should also put about a 50% load on it when you exercise it.

Yes it's 1800W max, I usually plug a 1440W battery charger into it for like 10 minutes, and then let it go at idle before and after the 1440W load.

 

[ATex7239]

I was thinking a change at hours or a year, like a car, but everyone was saying 2 years is fine, so I planned to do that. What do you think?

I’d say just do whatever the manufacturer recommends if you are not sure. That’s my opinion.

 

[spasm3]

Sure so what additive in oil goes bad? Most additives like the crude are naturally occurring minerals and chemicals. I don’t think calcium, boron, zinc etc. go bad.

This is a marketing gimmick so you buy new oil. Like I said in my original post, shake the bottle and pour it in.

Just my $0.02

If i remember one of the LSP JR tests, the anti foam either degrades or sticks to the bottle insides. Shaking the bottle did not seem to make a difference.

@HPL Plant Manager , @High Performance Lubricants might have insight here.

 

[Rand]

Yes it's 1800W max, I usually plug a 1440W battery charger into it for like 10 minutes, and then let it go at idle before and after the 1440W load.

What kind of charger is that? I usually use a heater.

 

[High Performance Lubricants]

Does oil really go bad after 1 year if it was previously opened? i see online that its 1 year once opened, and 5+ depending on the type if sealed. for example I buy 1qt oil for small engines that need 1/2qt, so from what I've read here id wait 2 years to change the oil since it won't hit the hours, but if the oil is going bad in a year should I just do a change in 1 year to use it up?

I wouldn’t worry about it. Resealed at room temperature the real life is probably greater than 5 years with ease

 

[shortyb]

I was thinking a change at hours or a year, like a car, but everyone was saying 2 years is fine, so I planned to do that. What do you think?


It's a small 1800W portable generator that stays inside, and I try to give it like 20 minutes every few months.

Moisture is a byproduct of the combustion cycle since there is water in gasoline. If you're only running for 20 minutes every few months, that stays in the oil and doesn't burn off completely. You don't need that living in the sump for 2 years. What are you trying to save here? the cost of a quart of oil or your generator? Just change the dang oil more often and don't worry about whether or not your opened bottle of oil will go bad on the shelf (it won't). Oil is cheap. I bet your generator isn't.

 

[benjy]

proper storage is key, i keep mine in my house!!! of course a tightly closed cap after opening

 

[Dave9]

Moisture is a byproduct of the combustion cycle since there is water in gasoline. If you're only running for 20 minutes every few months, that stays in the oil and doesn't burn off completely. You don't need that living in the sump for 2 years. What are you trying to save here? the cost of a quart of oil or your generator? Just change the dang oil more often and don't worry about whether or not your opened bottle of oil will go bad on the shelf (it won't). Oil is cheap. I bet your generator isn't.

Water is a byproduct of the combustion, because that's what it turns into from hydrogen and oxygen, not any water already in the gas. It's around 32% of the combustion byproducts, though particularly with ethanol blends, a much smaller % of exhaust may be water from that too.

If you run for 20 minutes, the oil is getting up to temperature and vaporizing off the moisture. If you change the oil prematurely, it still gets into the oil the next time you run the engine, and vaporizes off again. Unless you intend to change the oil after every time the engine runs, it doesn't make as much difference as you imply.

What are you hoping to improve here? Doing something with no real benefit is not just about trying to save the cost of oil. There are an unlimited number of ways I don't senselessly waste my time and money. I've never had an engine fail from using oil that sat around. Has anyone? Almost exclusively it is instead due to insufficient oil changes based on hours ran or extreme duty, cooking the oil at high temp.

As far as "proper storage", oil is designed to handle around 250F operating temp for its life cycle, so does it really matter if stored at 65F vs 95F? Doubtful. The oil in my garage sees down to about 20F in winter and 100F in summer, for upwards of a decade. I have not had any oil related engine problems, including equipment and vehicles over 20 y/o. At the same time, I recognize that air cooled engines tend to heat and degrade the oil faster, cannot run same # of hours per oil change. The manufacturer almost always specifies the OCI, though when they state X hrs or yearly, I ignore the yearly part unless it is also not too far off X hrs too, then mainly for convenience of seasonal outdoor equipment, I'll change it at end of season.

 

[John105]

Olive oil does.

I must not be a very good chef because I didn’t know that until this year. We had an unopened berio’s evoo dated 2022. My wife and I looked at each other and said
Almost simultaneously, “We’re using it!”

Can’t throw away $36. Likely bought it for $18.

 

[Ride_Red]

Oil in a capped bottle will be fine for a few years, no problem.

I change my small engines (mower, generators, etc) every two years at a maximum. Lawnmower oil still looks amber after two mowing seasons (about 60hrs total). Just think about the millions of lawnmowers that never get an oil change for years and the oil is still working. It would be reasonable to expect that oil in an engine would deteriorate faster than new oil in a capped bottle in the garage.

I always use the open jug or quart first, then top off with new oil. Car, motorcycle, small engine you name it. Not a problem using the open oil that has been sitting in the garage for a year or so. Been doing this for decades without any issues.

 

[Ride_Red]

I must not be a very good chef because I didn’t know that until this year. We had an unopened berio’s evoo dated 2022. My wife and I looked at each other and said
Almost simultaneously, “We’re using it!”

Can’t throw away $36. Likely bought it for $18.

Open a new bottle of olive oil and smell it. Then, open and smell the old bottle. I bet the you can tell the difference!

 

[cptbarkey]

Right now its just a generator that I'm talking about for the 1/2 quart per oil change. its a portable generator, I never need to use it, so it will never hit 50 hours. so I planned to do it every 2 years instead of 1 from what I read here.

If you do not already do this, I recommend starting and running the generator for about 20 minutes every few months. The moment you need the generator will be when you least expected it.