Fresh dirty motor oil.
May 9, 2012 5:35 PM Subscribe
I left the cap off my motor oil for weeks, and dust, leaves, twigs, spiders, and who knows what may have fallen in there. Can I still use it in my car? Should I filter it first somehow?
Response by poster: I'm talking about a 10 gallon plastic container full of motor oil, not the oil cap in my car. ;)
posted by brenton at 5:43 PM on May 9, 2012 [1 favorite]
posted by brenton at 5:43 PM on May 9, 2012 [1 favorite]
You're talking about the bottle of motor oil? A $3-$5 item? No, do not run that through the inside of your engine, just buy another one.
posted by contraption at 5:43 PM on May 9, 2012 [1 favorite]
posted by contraption at 5:43 PM on May 9, 2012 [1 favorite]
Oh, ten gallons. That might be worth trying to filter, but pouring it straight into the car sounds like a very bad idea.
posted by contraption at 5:44 PM on May 9, 2012
posted by contraption at 5:44 PM on May 9, 2012
Ah, never mind then :) I'm going to agree with the consensus to filter it. Although now I'm wondering why somebody is storing 10 gallons of oil. And I thought my car had an oil leak problem ;)
posted by COD at 5:48 PM on May 9, 2012
posted by COD at 5:48 PM on May 9, 2012
Use a funnel and cone style coffee filters to filter it would be cheap. Maybe a piece of window screen first to get rid of the knarly bits.
posted by Mitheral at 6:17 PM on May 9, 2012 [1 favorite]
posted by Mitheral at 6:17 PM on May 9, 2012 [1 favorite]
I suggest a funnel & sieve, and a similar size container. Don't return it to the original container
posted by artdrectr at 6:20 PM on May 9, 2012
posted by artdrectr at 6:20 PM on May 9, 2012
Best answer: Get the free strainers available at any place that sells auto paint. Cone shaped like a coffee filter but the bottom of the cone is a fine mesh. It will take FOREVER to pass the oil through a paper coffee filter - it's too fine.
A metal mesh coffee filter would work but I would not count on being able to use it for coffee again.
Paint strainer in a funnel will do the trick.
posted by BrooksCooper at 6:26 PM on May 9, 2012
A metal mesh coffee filter would work but I would not count on being able to use it for coffee again.
Paint strainer in a funnel will do the trick.
posted by BrooksCooper at 6:26 PM on May 9, 2012
Really? Depending on what got in there, you may not be able to filter it back out. Oil is a really good solvent of organic matter. You can't filter out the things that have dissolved into the oil. I wouldn't risk my car for the price of some new oil.
posted by Tandem Affinity at 6:27 PM on May 9, 2012 [2 favorites]
posted by Tandem Affinity at 6:27 PM on May 9, 2012 [2 favorites]
Throw it out.
posted by Sternmeyer at 7:04 PM on May 9, 2012 [1 favorite]
posted by Sternmeyer at 7:04 PM on May 9, 2012 [1 favorite]
Kitchen strainer. Then with something finer, along the lines suggested above.
Then think about the value equation. Oil = $xx. Car = $....x (actually enginge cost/repair). Are you happy to risk inconvenience and cost arising if there is any damage to the engine?
For the record, I suspect the risk is low. You will have gotten rid of just about all the foreign matter by straining/filtering, and when the oil goes in the sump, it is filtered by the oil filter before it goes to the bearings so any further particles will be stopped there (you do have a new filter right?). Dissolved impurities will be greatly diluted, and my gut says will do no harm but I stand to be corrected by someone who KNOWS (not thinks) differently.
posted by GeeEmm at 7:10 PM on May 9, 2012
Then think about the value equation. Oil = $xx. Car = $....x (actually enginge cost/repair). Are you happy to risk inconvenience and cost arising if there is any damage to the engine?
For the record, I suspect the risk is low. You will have gotten rid of just about all the foreign matter by straining/filtering, and when the oil goes in the sump, it is filtered by the oil filter before it goes to the bearings so any further particles will be stopped there (you do have a new filter right?). Dissolved impurities will be greatly diluted, and my gut says will do no harm but I stand to be corrected by someone who KNOWS (not thinks) differently.
posted by GeeEmm at 7:10 PM on May 9, 2012
Take it somewhere that recycles used motor oil. Cost of motor > Cost of motor oil.
posted by randomkeystrike at 7:22 PM on May 9, 2012 [1 favorite]
posted by randomkeystrike at 7:22 PM on May 9, 2012 [1 favorite]
10 gallons? That's an enormous amount to store in a domestic setting.
Anyway, it's dirty. The reason you change the oil in your car is to take the dirty oil out and replace it with clean oil. Putting this stuff in your car would be like a reverse oil change to some extent.
That said, if my car was an old one and the bottle of oil was close to full, I might give filtering it a go. Try the old favourite of a stocking inside a funnel. Of course, by the time you buy a funnel, some stockings and a new 10 gallon bottle to pour it into (unless you have them already), you may find that it's not particularly worth the trouble and cost.
posted by dg at 7:41 PM on May 9, 2012
Anyway, it's dirty. The reason you change the oil in your car is to take the dirty oil out and replace it with clean oil. Putting this stuff in your car would be like a reverse oil change to some extent.
That said, if my car was an old one and the bottle of oil was close to full, I might give filtering it a go. Try the old favourite of a stocking inside a funnel. Of course, by the time you buy a funnel, some stockings and a new 10 gallon bottle to pour it into (unless you have them already), you may find that it's not particularly worth the trouble and cost.
posted by dg at 7:41 PM on May 9, 2012
What would be more expensive to replace? The oil, or your engine?
posted by deadmessenger at 7:57 PM on May 9, 2012
posted by deadmessenger at 7:57 PM on May 9, 2012
Has this stuff been sitting indoors or outdoors? How big a hole are we talking about in the top of this container? Do you have any reason to believe that roving bands of hooligans came along and put sand in there or something? If not, I'd use it after running it through a fiberglass screen (or maybe the stocking inside the funnel trick that dg suggested) and then run it through a pleated paper filter using a high pressure pump (such as the one built into my engine).
posted by Kid Charlemagne at 8:11 PM on May 9, 2012
posted by Kid Charlemagne at 8:11 PM on May 9, 2012
Throw it out.
What? No, recycle it. Seriously, in the big scheme of car costs, 10 gallons is not that much and it's too big of a gamble to attempt to use it.
posted by MaryDellamorte at 8:50 PM on May 9, 2012
What? No, recycle it. Seriously, in the big scheme of car costs, 10 gallons is not that much and it's too big of a gamble to attempt to use it.
posted by MaryDellamorte at 8:50 PM on May 9, 2012
Best answer: I would filter it (to get rid of the big stuff, bugs etc like you say). It's unlikely to be "dirty" in the sense of used motor oil is "dirty". Used oil contains crap from combustion, breakdown products from high temps, maybe bits of metal shavings...... Oil sitting outdoors with the cap off does not make it "dirty" like used oil.
posted by scalespace at 9:27 PM on May 9, 2012
posted by scalespace at 9:27 PM on May 9, 2012
Best answer: I'd be concerned about water in the oil. If you get enough water mixed in, your engine won't be long for this world. Did it get rained on while it was sitting uncapped?
posted by azpenguin at 10:03 PM on May 9, 2012
posted by azpenguin at 10:03 PM on May 9, 2012
Best answer: I left the cap off my motor oil for weeks, and dust, leaves, twigs, spiders, and who knows what may have fallen in there.
Outside or in a garage where there are no hurricane-like winds blowing crap around? If the latter, it strikes me as very unlikely that an open container of oil on a shelf in a garage is going to equal 3000 miles worth of metal shavings and combustion byproducts and bug parts.
Whenever you check your dipstick, the act of wiping it off leaves bits of paper or fiber in the oil.
Your oil filter, if it is like mine, was shipped in a cardboard box, not sealed in a baggie. Same with your air filter. Absent evidence that you've been blowing the output of your shop vac into this oil, or that the ceiling above it has been crumbling, if it was indoors, I suspect it's fine.
posted by zippy at 11:44 PM on May 9, 2012
Outside or in a garage where there are no hurricane-like winds blowing crap around? If the latter, it strikes me as very unlikely that an open container of oil on a shelf in a garage is going to equal 3000 miles worth of metal shavings and combustion byproducts and bug parts.
Whenever you check your dipstick, the act of wiping it off leaves bits of paper or fiber in the oil.
Your oil filter, if it is like mine, was shipped in a cardboard box, not sealed in a baggie. Same with your air filter. Absent evidence that you've been blowing the output of your shop vac into this oil, or that the ceiling above it has been crumbling, if it was indoors, I suspect it's fine.
posted by zippy at 11:44 PM on May 9, 2012
Response by poster: The container was sitting outside, under the overhang of a garage. It rained during this time, so the air was wet, and there may have been tiny amounts of splashing of water into the top. The opening is slightly bigger than on a gallon of milk.
The cost of oil is less than the cost of my new engine. But that equation is also true if someone bounced a golf ball off the outside of the container. The oil will always be cheaper than the engine, the question is whether or not the oil actually has a risk of damaging the car.
Sounds like if water got in there, then there is a real risk, but if not, probably not much risk. So I guess the real question now is, do I feel lucky?
posted by brenton at 12:22 AM on May 10, 2012
The cost of oil is less than the cost of my new engine. But that equation is also true if someone bounced a golf ball off the outside of the container. The oil will always be cheaper than the engine, the question is whether or not the oil actually has a risk of damaging the car.
Sounds like if water got in there, then there is a real risk, but if not, probably not much risk. So I guess the real question now is, do I feel lucky?
posted by brenton at 12:22 AM on May 10, 2012
Best answer: Don't sweat the water. Remember the saying - oil and water don't mix. So the oil will sit on the top of the water, or, the water will sink.
When you are filtering it, watch carefully for globules of water as you get to the bottom. Stop before they get into the filter/funnel/watever. If you think there might be a lot of water, pour from one container directly into another, watching for the change as you get down to the water. Then stop, and dispose of the oily water, and treat the oil as suggested above.
In fact, using clean empty milk containers as storage for both the oil and the water/residue will give you more flexibility in juggling them - don't forget to mark which is which!
posted by GeeEmm at 2:45 AM on May 10, 2012
When you are filtering it, watch carefully for globules of water as you get to the bottom. Stop before they get into the filter/funnel/watever. If you think there might be a lot of water, pour from one container directly into another, watching for the change as you get down to the water. Then stop, and dispose of the oily water, and treat the oil as suggested above.
In fact, using clean empty milk containers as storage for both the oil and the water/residue will give you more flexibility in juggling them - don't forget to mark which is which!
posted by GeeEmm at 2:45 AM on May 10, 2012
I think this is a little bit like what I tell my four-year-old daughter regarding tooth brushing. "You only need to brush the teeth you want to keep."
If you have a nice car with a nice engine, i.e., a car your want to keep, why mess with filtering the oil?
posted by starkraven at 4:38 AM on May 10, 2012
If you have a nice car with a nice engine, i.e., a car your want to keep, why mess with filtering the oil?
posted by starkraven at 4:38 AM on May 10, 2012
Get rid of it. Don't ruin your car.
posted by oceanjesse at 6:50 AM on May 10, 2012
posted by oceanjesse at 6:50 AM on May 10, 2012
Why bother? Even if it is super expensive motor oil -- let's say it was $1,000 for 10 gallons of oil. A new engine will be more costly than $1,000. Easy math, get new oil.
posted by Geckwoistmeinauto at 7:53 AM on May 10, 2012
posted by Geckwoistmeinauto at 7:53 AM on May 10, 2012
Even ten gallons of very good synthetic oil would cost less than replacing an engine. Granted, the chance that it messes up is small, but why take the chance? Get rid of it, and something tells me that you'll never forget to properly seal a container of oil again.
posted by chosemerveilleux at 8:47 AM on May 10, 2012
posted by chosemerveilleux at 8:47 AM on May 10, 2012
If you're going to filter it, leave it out in the hot sun all day, preferably in a black trashbag, to heat up. This will reduce it's viscosity safely, to make it flow quicker through whatever you filter it with.
Also, try not to disturb whatever sediment results, and pour especially slowly towards the bottom, leaving the last few cups in the oil jug (to be thrown away). It might be easiest to pour off into an intermediary container, then pour by bits into the filter funnel.
posted by IAmBroom at 10:25 AM on May 10, 2012
Also, try not to disturb whatever sediment results, and pour especially slowly towards the bottom, leaving the last few cups in the oil jug (to be thrown away). It might be easiest to pour off into an intermediary container, then pour by bits into the filter funnel.
posted by IAmBroom at 10:25 AM on May 10, 2012
10 gallons of motor oil?
Damn, I'm impressed by what you can get on Craigslist.
posted by Ruthless Bunny at 12:36 PM on May 10, 2012
Damn, I'm impressed by what you can get on Craigslist.
posted by Ruthless Bunny at 12:36 PM on May 10, 2012
Best answer: Please-- unless you have reason to believe some malevolent force-- say, adolescents in the neighborhood-- were spooning sugar in there by the pound, the amount of organic matter in there is going to be inconsequential, especially after a filtration pass, which I agree with. (fine mesh, not coffee filter, unless you want to be there so long your friends and relatives turn into oil) Also, you store oil outside-- a proper malevolent force can get past an oil cap. The organic shit will burn up in no time and it'll be fine. Likewise the water has probably evaporated if it ever did collect on the surface.
If you can't decide between this opinion, and the "throw it away" opinion, take the middle road and follow Dr. Bronner's advice: DILUTE! DILUTE! OK!
posted by Sunburnt at 1:29 PM on May 10, 2012
If you can't decide between this opinion, and the "throw it away" opinion, take the middle road and follow Dr. Bronner's advice: DILUTE! DILUTE! OK!
posted by Sunburnt at 1:29 PM on May 10, 2012
Water is not that big of a deal - oil isn't exactly known for mixing with water and if there is a small amount in there it will quickly leave the first time you get your engine up to temperature. I say this because the products of burning gasoline are pretty much carbon dioxide and water and if you have an engine that has a blow by issue, it'll first manifest itself as a few persistent drops of water or maybe a grayish emulsion on your dipstick (where the water condenses).
What Broom says about sediment (and any water that sank to the bottom - oil is lighter after all) is probably good advice.
posted by Kid Charlemagne at 2:49 PM on May 11, 2012
What Broom says about sediment (and any water that sank to the bottom - oil is lighter after all) is probably good advice.
posted by Kid Charlemagne at 2:49 PM on May 11, 2012
This thread is closed to new comments.
posted by COD at 5:41 PM on May 9, 2012