Letting Oil Drain Overnight

[Panos]

If I would not mind spending 50-100ml of new oil, then I would pour this amount in the engine filler when the drain stream is slower than my OCD can take. The new oil should push some old oil out in about a minute or so (I guess) then I would screw the drain bolt when the drain stream is again slower than my OCD can take. So almost the same result but in less than 5 minutes instead of 5 or 10 hours.
But I do not care enough that would make me spend even this small amount of new oil.
(that's why I spend 5 minutes in draining any new oil container in my engines lol, can't stand wasting every last drop )

 

[ZeeOSix]

The question is will draining the oil 12+ hours increase oil pump cavitation? My thought is it makes no difference once air is allowed to reach the pump.

The pump won't necessarily "cavitate", but in some rare case the pump may lose it's prime and oil pressure may not happen for too long of a time until it re-primes itself. I've never had it happen because oil pressure builds just as fast after an oil change regardless if the oil drained 30 minutes or 24 hours on all the vehicles I've let the oil drain for a long time. Most pumps seem to be tight enough that the oil inside them doesn't drain out even if the the sump is drained for a very long time.

 

[ZeeOSix]

Oil will drain out of the bearings & lifters anyway, whether the pan is full or empty. I “flood clear” crank it a few times to prime it.

Surface tension of the oil will leave the same film inside the bearings regardless if the sump is drained 30 min or 30 hours. You can tear down an old engine in a junk yard that's been sitting for years and there's still a good film of oil inside all the journal bearings.

 

[SureshR]

So how long does it take for the Endeavour oil pump to drain out? Wouldn’t removing the filter allow air in to allow the pump to drain?

The guidance I got is not to let the sump drain for more than ten minutes. It takes about 2.4 gallons of oil for a fresh fill that way.

 

[SureshR]

You could remove the oil retention valves in the head(s). Then you won't have to turn the car over.

Turn the car over AND shake it to get every last drop out. Maybe smack it with your palm a time or three.

 

[4WD]

When that dirty oil has drained and only dripping - pour a few ounces of clean oil in - and watch how fast clean oil comes out …
Think about that …

 

[4WD]

Turn the car over AND shake it to get every last drop out. Maybe smack it with your palm a time or three.

Then maybe hook compressed air to the filler …
Better yet … Going to read something else …

 

[Dave_T]

I let mine drain for at least a week. Seriously….why not figure out a way to flip the car over and get every last drop out

After mine sits for a week with the plug out I pour in 10 qts to flush out that very last drop, give that another week to drain and refill/plug it up!

 

[Skippy722]

If I let the oil drain over night the raccoons will wash their grubby little hands in the oil and steal my drain plugs!

I wish I was joking. I want to turn that raccoon into a hat.

 

[TiGeo]

If you aren't draining/filling 6x are you even changing your oil?

 

[Lubener]

Once the oil coming out the drain hole slows to an occasional drip, I put the plug back in place which is about five to ten minutes. I then fill the engine with new oil. The small amount left inside is negligible.

 

[TiGeo]

Once the oil coming out the drain hole slows to an occasional drip, I put the plug back in place which is about five to ten minutes. I then fill the engine with new oil. The small amount left inside is negligible.

Same.

 

[RooflessVW]

The last drop to fall should be the most contaminated.

How do you figure

 

[demarpaint]

I wonder if some of the same people worrying about letting the oil drain overnight use filters for two OCIs?

 

[Snagglefoot]

Sorry. Life is too short for all that. Drain oil. Plug back in as soon as it turns to a drip. Filter off. New filter on as soon as it turns to a drip. Also I will keep a filter on for a 2nd run. Onward to something else.

 

[hrv]

Sorry. Life is too short for all that. Drain oil. Plug back in as soon as it turns to a drip. Filter off. New filter on as soon as it turns to a drip. Also I will keep a filter on for a 2nd run. Onward to something else.

Yup this overnight stuff is way overkill... I warm mine up a bit....Drain the oil...go inside have a cup of coffee then but drain plug back in ..change filter fill and move on...

 

[vavavroom]

How do you figure

It's a frivolous claim.

 

[CharBaby]

If you aren't draining/filling 6x are you even changing your oil?

I am more impressed with how he pours the oil in the engine without spilling any.

 

[shortyb]

You guys are still gravity draining your oil? Amateurs .

2.3 gallon Manual Fluid Extractor

Amazing deals on this Manual Fluid Extractor at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

 

[doublebase]

I really don’t care either way, usually I’ll just drain it warm, let it drip for a few minutes, plug and fill it.

But yeah, I do believe draining it hot is going to get the maximum out as quick as possible. Ever really see the difference between a cold engine drain and an operating temp engine drain? That hot oil is blasting out.

Crazy idea...maybe try changing it hot, let it drain for 10-15 minutes. Change the filter of course. Fill it, let it run for five minutes, and then immediately drain one quart and replenish it with a new quart of oil. Often times I’m left with a quart or two when I’m forced to buy two five quarts jugs at Walmart. I could just try this^^
with the thought process that any remaining oil left in the crevices of the engine, pump, and oil galleries...will be diluted even further by spilling and filling a quart.

Would I do this^^^? Absolutely not. But it might help those who are truly concerned about the remaining amount of used oil left in that engine. Maybe, then again maybe not