From reading, oil changes in most engines will only replace 80% to 90% of used oil. Any management strategies to get to as close as possible to 100% new oil after each change cycle, power flushes, a double oil change with the second oil change after 50 miles etc, thanks.
The 10 percent solution
- Thread starter Dale_Knight
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Yea, maybe. After you shut down the engine wait 10 minutes to pull the plug. Then just pull the old filter while draining and you'll get more of the old oil out of the engine.
you will never get all the residual oils out of your engine no matter how hard you tried, for engines are designed with pockets of oil and oil galleries, and such to hold oil for various different purposes.
Doing double or triple oil changes just for the sake of getting rid of that little bit of oil remaining is just as silly for you are literally wasting good 80% of the fresh oil in an attempt to flush out 10% of the remaining oil, which gets diluted anyways.
No matter how hard you try, you are still wasting precious fossil resource.
:2cents:
Q.
Doing double or triple oil changes just for the sake of getting rid of that little bit of oil remaining is just as silly for you are literally wasting good 80% of the fresh oil in an attempt to flush out 10% of the remaining oil, which gets diluted anyways.
No matter how hard you try, you are still wasting precious fossil resource.
:2cents:
Q.
I will usually leave my filter and plug out for about 30 to 45 minutes, set up for the fill, have a beer or 2, wash up from the drain.
Originally Posted By: wcbcruzer
It would be scary if you got 100% of the oil out. Cause then when you go to start it, there will be NO oil coating your internal engine parts.
Lol dude, we are talking about 100% oil replacement, have another beer for me though.
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It would be scary if you got 100% of the oil out. Cause then when you go to start it, there will be NO oil coating your internal engine parts.
Lol dude, we are talking about 100% oil replacement, have another beer for me though.
.
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JHZR2
Staff member
I wouldnt worry about it. No offense, but neither of your engines are worth fretting about compared to the waste of oil from refilling and re-draining; and neither will self-destruct from having even 20% used oil.
Its part of the design constraints of the engines...
Letting it drip and drain for an extended amount of time (e.g. overnight) is likely as best as you can do.
Good luck,
JMH
Its part of the design constraints of the engines...
Letting it drip and drain for an extended amount of time (e.g. overnight) is likely as best as you can do.
Good luck,
JMH
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Seem to recall someone who would open up the drain plug, let it drain half an hour or so, pour a fresh quart in the fill hole to wash through any leftover old oil, then let it drain another half hour. Though honestly I've never worried about it myself.
Originally Posted By: JHZR2
I wouldnt worry about it. No offense, but neither of your engines are worth fretting about compared to the waste of oil from refilling and re-draining; and neither will self-destruct from having even 20% used oil.
Its part of the design constraints of the engines...
Letting it drip and drain for an extended amount of time (e.g. overnight) is likely as best as you can do.
Good luck,
JMH
Thanks JMH, no offense taken about me using mediocre engines however in the greater scheme of things it seems that thinking of a 10% - 20% dilution factor with used oil for oil changes as normal is an engineering fault which we think is acceptable because thats the way it always has been. Surely there must be a better way to change engine oil than what our great-grandads did and which will give better result in terms of greater engine longevity.
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I wouldnt worry about it. No offense, but neither of your engines are worth fretting about compared to the waste of oil from refilling and re-draining; and neither will self-destruct from having even 20% used oil.
Its part of the design constraints of the engines...
Letting it drip and drain for an extended amount of time (e.g. overnight) is likely as best as you can do.
Good luck,
JMH
Thanks JMH, no offense taken about me using mediocre engines however in the greater scheme of things it seems that thinking of a 10% - 20% dilution factor with used oil for oil changes as normal is an engineering fault which we think is acceptable because thats the way it always has been. Surely there must be a better way to change engine oil than what our great-grandads did and which will give better result in terms of greater engine longevity.
.
Patman
Staff member
Engines last a pretty long time nowadays though, when was the last time you heard of someone's engine needing a rebuild before 150,000 miles unless it was completely abused?
Most well maintained engines these days can easily go 200-250k before a rebuild, even with oil changes that only allow 80-90% of the old oil to be removed.
Most well maintained engines these days can easily go 200-250k before a rebuild, even with oil changes that only allow 80-90% of the old oil to be removed.
Quote:
Originally Posted By: wcbcruzer
It would be scary if you got 100% of the oil out. Cause then when you go to start it, there will be NO oil coating your internal engine parts.
Lol dude, we are talking about 100% oil replacement, have another beer for me though.
A certain percentage of the oil in your vehicle coats the internal parts and is there when you start the vehicle so that there is at least some lubrication. Removing that coating would be far worse for your engine than having 10% used oil. If you got 100% of the oil out and replaced it there would be no coating of oil when you went to start it because the parts would have to wait for the oil to be pumped.
The used oil is probably just goipng to be extra anyway. If the factory put in 6 quarts of oil in my truck and 10% remained when I drained it that would mean that .6 quart would remain in the engine to which I would add 6 new quarts. Now I would assume that the engine would hold that same .6 quart when drained no matter how much oil was put in it, otherwise the oil level would build with each oil change. So essentially I get 6 fresh quarts with a little over a half a quart of used oil with each change. I don't see a problem.
Originally Posted By: wcbcruzer
It would be scary if you got 100% of the oil out. Cause then when you go to start it, there will be NO oil coating your internal engine parts.
Lol dude, we are talking about 100% oil replacement, have another beer for me though.
A certain percentage of the oil in your vehicle coats the internal parts and is there when you start the vehicle so that there is at least some lubrication. Removing that coating would be far worse for your engine than having 10% used oil. If you got 100% of the oil out and replaced it there would be no coating of oil when you went to start it because the parts would have to wait for the oil to be pumped.
The used oil is probably just goipng to be extra anyway. If the factory put in 6 quarts of oil in my truck and 10% remained when I drained it that would mean that .6 quart would remain in the engine to which I would add 6 new quarts. Now I would assume that the engine would hold that same .6 quart when drained no matter how much oil was put in it, otherwise the oil level would build with each oil change. So essentially I get 6 fresh quarts with a little over a half a quart of used oil with each change. I don't see a problem.
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Get a preluber ..but plumb it to a clean oil supply. Make some trick hook up ... and calculate what you think is your cached oil amount ...and just push that through to the sump. There is very little cached oil in most engines. That left over is typically just that coating the parts. Some have more. The rotary engines ..some others
Non issue.
It dosen't matter . All the "tricks" people use to try to get a few more drips of oil out are counterproductive to the desired intent of the procedure.
I keep seeing people say they only get 80-90% of the oil out during an oil change. Where does this number come from?? I bet you are getting a lot more oil out than you think.
In a properly designed engine, you want the oil circulating through the engine to return to the oil pan as quickly as possible, not laying around in puddles in the heads and valleys where it is not doing anything. That's why these areas have oil drain back holes. Pressurized oil galleries and passages will of course retain most of their contents after shut down but this certainly would be less than 10% of the total volume in most engines.
There has been mention in this thread about people pouring fresh oil into the fill hole to flush the engine out but all this would do is flush out the drain back holes which better already be empty by then. It does not flush out any oil galleries or passages which is where any leftover oil might be found.
But just think, that little bit of oil that does always remain in the engine might still contain some of your factory fill even after a couple hundred thousand miles.
In a properly designed engine, you want the oil circulating through the engine to return to the oil pan as quickly as possible, not laying around in puddles in the heads and valleys where it is not doing anything. That's why these areas have oil drain back holes. Pressurized oil galleries and passages will of course retain most of their contents after shut down but this certainly would be less than 10% of the total volume in most engines.
There has been mention in this thread about people pouring fresh oil into the fill hole to flush the engine out but all this would do is flush out the drain back holes which better already be empty by then. It does not flush out any oil galleries or passages which is where any leftover oil might be found.
But just think, that little bit of oil that does always remain in the engine might still contain some of your factory fill even after a couple hundred thousand miles.
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Quote:
But just think, that little bit of oil that does always remain in the engine might still contain some of your factory fill even after a couple hundred thousand miles
Long before that, it's residing in the engine as a deposit ..but the point has merit.
But just think, that little bit of oil that does always remain in the engine might still contain some of your factory fill even after a couple hundred thousand miles
Long before that, it's residing in the engine as a deposit ..but the point has merit.
Originally Posted By: Gary Allan
Get a preluber ..but plumb it to a clean oil supply. Make some trick hook up ... and calculate what you think is your cached oil amount ...and just push that through to the sump. There is very little cached oil in most engines. That left over is typically just that coating the parts. Some have more. The rotary engines ..some others
Gary:
I agree with the general idea that this is a non-issue, but engines "trap" more old oil than most suspect. The I-4 used in the Camry and Hybrid Camry has 0.8 quarts of oil that's somewhere between the pump and where it can drain back to the sump, and there's absolutely NOTHING the owner, changer, or whoever, can do to get this oil out at a change, other than completely disassembling the engine. In other words, almost a full quart remains behind in this engine when you change oil, even if you let the thing drain for hours and hours. I assume that the presence of old oil in the plumbing is already factored into the change interval recommendations we see from the manufacturers. BTW, I got this info from the tech pubs from Toyota regarding the 2AZ engine: 4.5 quarts for an oil and filter change, 5.3 qts for a true "dry fill" after engine rebuild.
Get a preluber ..but plumb it to a clean oil supply. Make some trick hook up ... and calculate what you think is your cached oil amount ...and just push that through to the sump. There is very little cached oil in most engines. That left over is typically just that coating the parts. Some have more. The rotary engines ..some others
Gary:
I agree with the general idea that this is a non-issue, but engines "trap" more old oil than most suspect. The I-4 used in the Camry and Hybrid Camry has 0.8 quarts of oil that's somewhere between the pump and where it can drain back to the sump, and there's absolutely NOTHING the owner, changer, or whoever, can do to get this oil out at a change, other than completely disassembling the engine. In other words, almost a full quart remains behind in this engine when you change oil, even if you let the thing drain for hours and hours. I assume that the presence of old oil in the plumbing is already factored into the change interval recommendations we see from the manufacturers. BTW, I got this info from the tech pubs from Toyota regarding the 2AZ engine: 4.5 quarts for an oil and filter change, 5.3 qts for a true "dry fill" after engine rebuild.
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Well, how would this prevent a pre-luber from purging cached oil??
It would simulate the oil pump by infusing fresh oil to chase out the cached used oil. It would be a pre-luber ..but not used as a pre-luber (a rose by any other name
). Call it a cached oil purger.
The only reason I said it is that someone who WANTS to do this needs a modality to accomplish it. That's what I pulled out of my behind. I wouldn't bother, myself ..but I do plenty of stuff that Bill in Utah wouldn't do unless you paid him.
..and yes, I agree it's a non-issue in most cases. In the case of Camry Hybrid, one prays that the near 50% of the sump is not highly contaminated with something like coolant ..requiring many short oil changes to truly purge residuals to an acceptable level.
..and while there are surely exceptions, one of the most noted I mentioned, the vast majority don't have a whole lot outside of the filter.
The only reason I said it is that someone who WANTS to do this needs a modality to accomplish it. That's what I pulled out of my behind. I wouldn't bother, myself ..but I do plenty of stuff that Bill in Utah wouldn't do unless you paid him.
..and yes, I agree it's a non-issue in most cases. In the case of Camry Hybrid, one prays that the near 50% of the sump is not highly contaminated with something like coolant ..requiring many short oil changes to truly purge residuals to an acceptable level.
..and while there are surely exceptions, one of the most noted I mentioned, the vast majority don't have a whole lot outside of the filter.
for my Tacoma
oil and filter change (5.5 US qts)
Dry fill (6.3 US qts)
Its in there and it aint coming out like Ekpolk stated we tear that motor down. The engine is built with grooves in the bearings to retain more oil during shutdown. THere are galleys in the block, valleys in the headsm oil is reatined inside many camshafts that operate oil activated variable valve timing systems. There are oil jets for the cylinders and oil jets for the timing chains and what the oil pump retains itself.
oil and filter change (5.5 US qts)
Dry fill (6.3 US qts)
Its in there and it aint coming out like Ekpolk stated we tear that motor down. The engine is built with grooves in the bearings to retain more oil during shutdown. THere are galleys in the block, valleys in the headsm oil is reatined inside many camshafts that operate oil activated variable valve timing systems. There are oil jets for the cylinders and oil jets for the timing chains and what the oil pump retains itself.
The only time it is important to exchange 100% of the oil is in case of contamination. Say someone poured antifreeze in the oil fill, or did something else stupid. Drain, fill, run for a minute, drain, fill, run for a minute, etc., etc. until the engine is clean.
Otherwise, don't worry.
Otherwise, don't worry.
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