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Discussion Starter · #1 ·
The kind of things that happen to me: Just went to add oil to car. Right next to black gallon of oil was black gallon of drain cleaner. Didn't add much. Haven't/won't start car. Other than draining oil/replacing, is there anything else I can/should do?
 

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Discussion Starter · #3 ·
oops, Add a bunch of oil to flush it dilute immediately. What drain cleaner?
Zep Liquid Heat. Maybe 6oz? Oil is pretty full.
 

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Zep Liquid Heat. Maybe 6oz? Oil is pretty full.
Yeah but throw some more oil in the top end to flush that out immediately if you have not done so already. If it were me, I'd get a bunch of cheap oil and do multiple flush/fills. With 6 oz and immediately flushed out, probably didn't damage anything really (you have 200 oz of oil in there), just trickles down to the pan. You could even pop the valve cover and look for any indications that the drain cleaner was there but really, probably fine.
 

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Do not run the car until you flush! Drain cleaner have plenty of water in it, and water does not compress/combust. You don't want to hydrolock your motor. Drain, refil with cheap oil, turn by hand several times, drain again. Then re-fill with cheap oil again, turn by hand, drain. Then take plugs out, filter out, clean plugs, put new oil filter, fill with cheap oil, and put some engine cleaner in the oil. Start, and listen to how the engine would run. Run maybe for a few minutes if runs ok.

Drain, replace filter, plugs, and re-fill with good oil. Change that after 500 miles. Hope you could bring it back and not much damage done to internals with caustic drain cleaner.
 

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Other than draining oil/replacing, is there anything else I can/should do?
I would not panic about this. First drain cleaners attack organics so there will be few in a synthetic oil fill. Might be different if you had standard oil, but there might be some organics settled to the bottom of the pan. They were likely burned up going through the combustion chamber if you have no leaks for air to get into the crankcase.
The cleaner is designed likely to sink in water, most are but I don't know the product. Water goes to the bottom, so the cleaner will too. Draining the oil should be enough and you will see the cleaner come out first. There is a side plug that you could use, jack the car up so that is the low point, concentrate the cleaner. Not likely going to do much more and my last suggestion to pull the pan and use this as an excuse to check for plastic and other things in the bottom. Also good penance for the mistake and the car will respect that, especially if you use a new gasket and take the time to clean the temp sender/ level indicator. Then give the rest a good wash, and that should take care of any residue.
 

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All good advice. You have about 6 oz. of fluid dispersed (presumably) among about 7 quarts of oil. So like others have said, don't start the engine until you flush out the bad oil.

After you either suck up oil from the dipstick tube with a Mittyvac or similar and pull the drain plug, I think I would add 2-3 quarts of cheap oil with the drain plug out and let the oil run right through. Since you haven't started the motor, none of the contaminated oil should be distributed anywhere throughout the block.

Then I would do a couple of fill and flushes with engine on as others have suggested. Even if you have 1 or 2 oz. leftover (unlikely) I don't think that is enough to cause any issues. A liter of oil is slightly more than a quart. 32 oz. in a quart (33 in a liter). So even if you were a 1/2 quart low, you have about about 208-210 ounces of oil with maybe a couple of ounces of bad stuff.

After a few oil flushes and an underwear change!!! LOL, you should be good to go!

Regards,
Jerry
 
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If you have the oil cap closed. I'd leave it open.
Some drain cleaners produce a significant amount of gas when it breaks down fat, so I'd say preventing pressure build-up maybe helpful.
Also drain cleaners do tend to cause significant corrosion on metal pipes. It will have plenty of oil in the motor so I wouldn't worry about it much. But definitely. Definitely clean the whole thing out. A LOT OF OIL!

Good luck to the OP.

Best,
Gabe

I would not panic about this. First drain cleaners attack organics so there will be few in a synthetic oil fill. Might be different if you had standard oil, but there might be some organics settled to the bottom of the pan. They were likely burned up going through the combustion chamber if you have no leaks for air to get into the crankcase.
The cleaner is designed likely to sink in water, most are but I don't know the product. Water goes to the bottom, so the cleaner will too. Draining the oil should be enough and you will see the cleaner come out first. There is a side plug that you could use, jack the car up so that is the low point, concentrate the cleaner. Not likely going to do much more and my last suggestion to pull the pan and use this as an excuse to check for plastic and other things in the bottom. Also good penance for the mistake and the car will respect that, especially if you use a new gasket and take the time to clean the temp sender/ level indicator. Then give the rest a good wash, and that should take care of any residue.
Isn't synthetic oil still organic? Organic is anything that consists of C-H bonds. Synthetic oils or "oil" largely consists of C-H bonds.
LOL sorry. Just what I major in.
So I think it is reasonable to think that speed is the KEYY
remove that oill!!
 

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Organic is anything
Organic was not the best choice of words, but KISS applies. I have read more because I was curious. Modern cleaners don't attack plastic or metal. They seem to attack fibrous material and somehow bond in CO2 to soften and lighten the clog. Also some of these cleaners are actually a synthetic plant oil? Not sure about how or what that means.
In any event that could complicate things a tad so the OP needs to do a test to evaluate what is going on. Very simple test, take a clear glass and half fill it with oil, then poor an oz of the cleaner on top and see what happens. One of two things will happen it will either stay in a group and sink to the bottom or it will mix with the oil. If it is one of these plant oils it might mix with the oil, but I doubt it. If it stays grouped then there is little issue. It will just come out grouped.
 

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I wouldn’t start the car
Id drain it
Full it to the brim with cheap oil, drain it

Then fill with cheap oil and run it for a bit then drain

Then fill with proper oil and chance filter and relax
 

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I wouldn’t start the car
Id drain it
Full it to the brim with cheap oil, drain it

Then fill with cheap oil and run it for a bit then drain

Then fill with proper oil and chance filter and relax
This. 6oz isn't much and you haven't tracked the car with water in the oil - it'll be totally fine :)
 

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Discussion Starter · #14 ·
TY all for the advice. Of course, I was panicking when it first happened, but after calming down and thinking about it, I figured "It's only a little bit, I didn't start the car, and, assuming this stuff sinks, it should be the first thing they see when the open the drain plug." And it was. It was then followed by 200oz of oil, so that probably was enough to clean everything out. Got the car back Monday, and have driven about 50mi with no problem. Bonus: pretty sure there's no grease or hair in my oil pan.
 

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Edit: nvm, didn't see your latest reply.


Lol you'll be fine.

If you haven't started the engine yet, drain the oil right now and you'll likely get most of it out as it probably went straight down into the oil pan. You can also remove the oil pan and let it drain over a day if you really wanna be anal, but I wouldn't bother.

Get some cheap synthetic 5W-30 oil from Wal-Mart.
Pour 6L in and one of synthetic ATF (like Mobil1).
Run the engine till temps are warm.
Drain all oil.
Refill with your original oil of choice and replace filter.

Done.
 

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Lol, Shady, I had the same thought. Would have given that girl an older hot rod fluid flush.

This reminds me of a time when my brother had a gf who topped off her Honda with a quart of roundup… Seized the motor pretty quickly.
 

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I'd use a vacuum sucker to get the last bits out. The drain plug boss does not get the last bits out and drain cleaner sinks in oil so there will still be some in the pan after the drain out. Or just remove the lower drain pan.and dump it all out.
 
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