Letting Oil Drain Overnight

[SavetheRimBrake]

I have a 1.5t Honda and don’t have this issue. Honda installed a feature where fuel mixes with the oil and helps the trace films evaporate between oil changes and every time you start your car, at least that’s what I read here

 

[Number_35]

The longer you drain the better.

Whenever someone else does my oil changes the oil is darker on the dip stick afterwards. They replace the drain plug too early.

I also open the fill cap when I let the oil drain.

When I worked as a tune-up/oil change/lube tech, we (the franchise) advertised a 10-minute oil change which included a 15-point inspection.

Ten minutes was unrealistic, but it's likely the oil drained no more than six or seven minutes, because we still had to pump in the new bulk oil.

As I recall, calling the inspection "15-point" was optimistic; four of the points were a visual inspection of the four tires. A visual inspection of tire pressure, particularly radials, was not particularly helpful.

 

[TiGeo]

I'm only here for @TiGeo's memes. I don't even like oil.

Pull the drain plug and then change the filter. By that time the oil has slowed down to a drip and pop the plug back in. Don't understand why anyone would wait around any longer?

 

[buster]

Chapter 1 of the American Psychological Association Textbook: BITOG oil disorders.

 

[TiGeo]

Chapter 1 of the American Psychological Association Textbook: BITOG oil disorders.

Gold.

 

[DGXR]

I have to question exactly how much more oil is draining after approx 30 minutes, and also question the benefit (if any) to this tiny additional drain. Also consider that many vehicles have a very fast idle on the initial cold start to light off the cats (mine is ~2400 rpm) and not every vehicle has a flood mode to prime the system. Generally I think it's better to finish the service and restart / check fluid levels while the engine is still warm.

 

[hrv]

10 pages lets try for 11

 

[TiGeo]

10 pages lets try for 11

 

[userfriendly]

View attachment 158603

Who's fault is that? You've posted 15x so far on this thread.

 

[TiGeo]

Who's fault is that? You've posted 15x so far on this thread.

And you just responded...1 more!

 

[CR94]

View attachment 158530

Your photograph nicely illustrates my latest method, except that you omitted a couple of minor upgrades.
1) A piece of heavy wire wrapped loosely on the hose at the top of the recovery bottle, which weights the hose to keep it from flying upward out of the bottle, and also keeps the exterior of the hose from getting submerged and oily (when pumping 2) Concrete hunk and/or filled 1-gallon milk bottles beside the oil recovery bottle to reduce the chance of accidentally kicking it over.

 

[billt460]

Another fact to consider if you live near the equator, is that gravity is slightly less. So be sure to factor that into allowing a slightly longer drain time.

 

[racer12306]

Another fact to consider if you live near the equator, is that gravity is slightly less. So be sure to factor that into allowing a slightly longer drain time.

Might require a day and a half rather than just the standard day for effective drainage.

 

[TiGeo]

Another fact to consider if you live near the equator, is that gravity is slightly less. So be sure to factor that into allowing a slightly longer drain time.

And in the southern hemisphere it will spiral out the drain in the opposite direction...haha

 

[Skippy722]

Your photograph nicely illustrates my latest method, except that you omitted a couple of minor upgrades.
1) A piece of heavy wire wrapped loosely on the hose at the top of the recovery bottle, which weights the hose to keep it from flying upward out of the bottle, and also keeps the exterior of the hose from getting submerged and oily (when pumping 2) Concrete hunk and/or filled 1-gallon milk bottles beside the oil recovery bottle to reduce the chance of accidentally kicking it over.

I didn’t even think of that, you’re a genius!

 

[racer12306]

And in the southern hemisphere it will spiral out the drain in the opposite direction...haha

Does that counteract the additional time needed due to lower gravity?

 

[CleanSump]

What Mercedes has in the manual for draining the OM642 V6 Diesel if one chooses to pull the plug instead of vacuuming.

"Leave oil drain hole open for at least 5 minutes until the engine oil has flowed back into the engine oil pan, otherwise the total quantity of engine oil will not be drained."

At least a whole, whopping, 5 Minutes! Oh, I forgot, the maintenance plan is designed so the engine blows up the day after the warranty ends.

 

[garageman402]

Greatest little tool since sliced bread. While the oil drains, I go in the house, shower and eat supper, sleep peacefully til am, then go out to a COLD engine, remove the filter, fill the new one up and finish changing oil.

You're missing the oil that is released when you remove the filter. That cold oil is still slowing creeping down into the pan while you're installing the new filter (pre-filled I hope) & adding fresh oil. You let it drain all night, but missed some. At least crack the filter when hot to let air in.

 

[garageman402]

197 comments in 90 hours!! Is that a BITOG record? Do I get a special award? LOL Glad I cheered up a holiday weekend for some folks....

But seriously, all I really wanted to know is if the oil pump will "cavitate" or lose prime due to the pickup being exposed to air for an extended length of time. It seems to me as soon as air is introduced into the system from the pickup being uncovered, & through the pressure side of the filter when it is removed, any loss of prime or cavitation would be immediate so length of time is really no issue in this case.

 

[philipp10]

I like to let the oil drain overnight (or all day) or longer. I know there will always be oil left in the motor, but at least that much more is out. My high school friend’s dad had a gas station & he let his car drain all day, said the oil seemed to stay clean longer.

I have now been told that allows the pump to cavitate resulting in dry startup. I disagree, as soon as you take the filter off, air is allowed in the system so the pump will fully drain. I pre fill the filter & “flood clear” to prime the system before starting it anyway.

Is there any fact here? Or just another old mechanic’s tale?

you should also shake and turn your car upside down to get out EVERY drop...