Rubbish advice on BITOG these days...

[Ducked]

Originally Posted By: ZeeOSix
If particles are suspended in the oil while the engine is running then an efficient full flow oil filter is going to remove basically all of those particles unless they are smaller than ~10 microns.



I see you in the oil filter forum quite often, so you should know that if an oil filter is 99% efficient at 20 microns that it's also about 80% efficient at 5 microns. A filter like that is basically going to take out everything that is suspended in the oil when the oil goes through the filter.



But it didn't

Originally Posted By: ZeeOSix
Draining the oil hot isn't going to remove large amounts of built up debris in the sump


But it did.

No offence, but given the choice between your theory about my car and my observations on my car, I'm going to choose the latter.

I suppose the filter thing could be explained by the filter being clogged and in bypass, which a lot of stuff in the oil could cause, though I think its unlikely because the previous owners seem to have dealer-maintained it by the book (while doing nothing about the rust. People are strange).

I gave it 2 or 3 changes at ridiculously short intervals, but I've stopped doing that now so I should probably try and check the current status.

I can't think of an explanation for metal in the drained oil that doesn't involve metal in the drained oil, and apparently neither can you.

 

[ZeeOSix]

Originally Posted By: Ducked
Originally Posted By: ZeeOSix
I see you in the oil filter forum quite often, so you should know that if an oil filter is 99% efficient at 20 microns that it's also about 80% efficient at 5 microns. A filter like that is basically going to take out everything that is suspended in the oil when the oil goes through the filter.

But it didn't

Use better oil filters. Have you ever cut open your oil filters to inspect for debris and what kind? You have metal in the oil because your engine is eating itself to death.

Originally Posted By: Ducked
Originally Posted By: ZeeOSix
Draining the oil hot isn't going to remove large amounts of built up debris in the sump

But it did.

No offence, but given the choice between your theory about my car and my observations on my car, I'm going to choose the latter.

I suppose the filter thing could be explained by the filter being clogged and in bypass, which a lot of stuff in the oil could cause, though I think its unlikely because the previous owners seem to have dealer-maintained it by the book (while doing nothing about the rust. People are strange).

I gave it 2 or 3 changes at ridiculously short intervals, but I've stopped doing that now so I should probably try and check the current status.

I can't think of an explanation for metal in the drained oil that doesn't involve metal in the drained oil, and apparently neither can you.


How did you know it did? I'm not doubting what you're saying, but obviously this car was owned by someone else and you have no exact knowledge of how it was treated or maintained. If he claims it was always "dealer maintained" then the oil was probably always drained hot, so if you think having debris in the sump is from draining the oil when cold then you're way off track.

 

[Shannow]

Zee0Six,
given your an engineer, and have years (not many) more experience than I, what does every manual for every piece of equipment you've come across, pumps, hydraulics, engines, etc. and et. al. state about draining the oil immediately after running, or cold ?

(hint...operating temperature, straight after shutdown)

Why are you so vehemently arguing against the knowledge and recommendations of the OEMs ?

eg....

Cat
Quote:
Do not drain the oil when the engine is cold. As the oilcools, suspended waste particles settle on the bottomof the oil pan. The waste particles are not removedwith the draining cold oil. Drain the crankcase withthe engine stopped. Drain the crankcase with theoil warm. This draining method allows the wasteparticles that are suspended in the oil to be drainedcorrectly.Failure to follow this recommended procedure willcause the waste particles to be recirculated throughthe engine lubrication system with the new oil.


detroit

Quote:
NOTE:Change the engine oil only when theengine is at an operating temperatureof approximately 82°C (180°F).


PCM engines

Quote:
IMPORTANT: Change the engine oil when the engine is warm from operation. Warm oil fl ows more freely, and allows more foreign material and impurities to be removed.



Mercury (adapted from road going engines often).

Quote:
IMPORTANT: Change oil when engine is warm from operation, as it flows more freely,carrying away more impurities.


hydraulic system

Quote:
While the fluid is at operating temperature, completely drain the system, paying attention to the reservoir, all lines, cylinders, accumulators, filter housings or any area of fluid accumulation. Also, replace the filters.


and with regard to flushing them...
Quote:
High Turbulence, High Fluid Velocity, Low Oil Viscosity — Flushing is enhanced by high turbulence flushing conditions by lower flush oil viscosity and increasing oil flow rates.

High Flush Oil Temperature — This reduces viscosity, increases turbulence and increases oil solvency. Temperatures in the range of 175 to 195 degrees F are generally targeted.


I just don't get how with your training you could even posit that cold is the same as hot.

 

[02SE]

Years ago I experimented with cold and hot oil changes. Draining oil cold, there were always some 'debris' sitting in the oil pan after no more oil drained out, than if I drained the oil while it was hot, at full operating temperature. This was on my own strictly maintained vehicles, invariably with synthetic oil, and at conservative OCI's.

I verified the 'debris' sitting in the oil pan with a bore scope that has a very clear image.

When the oil was drained while at operating temperature, the oil pan would be essentially spotless when inspected with the bore scope.

Just some completely anecdotal evidence. But as a result of what I saw with my own experiment on my vehicles, and what I've seen in countless engines I have worked on, I always change my oil while it is hot.

 

[ZeeOSix]

For starters, I'm NOT advocating to drain oil when cold instead of hot. I'm saying if you happen to drain the oil cold and let it drain long enough you're essentially doing the same thing if the engine is clean - a sludged up engine is a different animal. And of course most manuals are going to say drain the oil hot or at least warm because it drains faster - less time required to drain to a slow drip.

Draining the oil when fully hot or pretty warm (say above 125 deg F) will certainly help drain the sump faster and probably get you a hair more oil out, but it's not going to leave less accumulated deposits in the sump if your engine is well maintained and clean. The only suspended particulate in the oil should be what an efficient oil filter hasn't caught - ie, particles that are smaller than 20 microns. Any particles that fall out of suspension will do so at every engine shutdown and accumulate at the bottom of the sump, and if they don't move and become re-suspended during subsequent engine operation and driving g-forces causing the oil to slosh around in the sump, then they probably won't be swept out of the sump regardless if the oil is drained hot or cold. I would definitely drain oil hot on something that doesn't have a full flow oil filter, like my lawn mower.

If you drain the sump while cold (and I mean warmer than say 50~60 F), you would just have to wait longer to get the full volume drained out. I've probably only drained a sump cold twice in my life, and when I did so I let it drain overnight just to make sure it completely drained. I usually wait 30~45 min after shutdown to drain the oil, so it's probably still around 125~150 deg F.

Of course if you neglect your oil and filter changes and the engine is all sludged up, then draining fully hot might help get a bit more sludge out of the sump. But on a clean engine where the sump is kept clean from on time oil & filter changes it's not going to cause debris to remain in the sump if the oil is drained cold and allowed to completely drain.

http://www.cartalk.com/content/which-better-changing-your-oil-when-engine-hot-or-cold

http://www.cumminsforum.com/forum/general-diesel-discussion/393160-oil-drain-hot-cold.html

All kinds of talk of draining the oil hot or cold.
https://www.google.com/?gws_rd=ssl#q=draining+oil+when+cold

 

[ZeeOSix]

Originally Posted By: 02SE
Years ago I experimented with cold and hot oil changes. Draining oil cold, there were always some 'debris' sitting in the oil pan after no more oil drained out, than if I drained the oil while it was hot, at full operating temperature. This was on my own strictly maintained vehicles, invariably with synthetic oil, and at conservative OCI's.

I verified the 'debris' sitting in the oil pan with a bore scope that has a very clear image.

When the oil was drained while at operating temperature, the oil pan would be essentially spotless when inspected with the bore scope.

Just some completely anecdotal evidence. But as a result of what I saw with my own experiment on my vehicles, and what I've seen in countless engines I have worked on, I always change my oil while it is hot.


Interesting info. Was this all on the same bike? ... meaning if you did a cold oil change and saw something in the oil pan, and then did the next oil change hot, did the debris you saw in the oil pan disappear?

How do we know that doing all those wheelies and high lean angle corners didn't sweep the debris out of the bottom of the oil pan to get it re-suspended so the oil filter caught it all?

 

[Shannow]

There's plenty of stuff that's held up in circulating oil by the dispersents that aren't filterable...e.g. soot in a UOA is clearly not filterable, it hangs around, and builds up to whole numbers of percents. Needs the agitation and flow to keep it moving, or it slowly settles out, to be re circulated next time the thing is run...

Varnish a sludge precursor is also far less soluble in cold oil than hot...and when hot, is clearly not filterable.

So leaving a sump to cool gives you the "best" of both worlds...varnish isn't soluble, and starts to drop out. Soot and the like drop out.

And at the bottom of the sump, form a more viscous semi solid natured paste, that WON'T drain out if you pull the plug...it will sit there until you warm the engine up again, then get either re-dissolved (varnish) or picked up and circulated (soot and the like)...bingo, your brand new oil is dirty again...

Drain it hot, the soot is still dispersed, the varnish is still dissolved, and physically more of the total volume comes out the drain plug...thus manufacturer's recommendations.

Absence of the paste of settled varnish and soot means that heavy particles rather than getting "stuck in the mud" have an opportunity to flow out as well.

And no, varnish and soot aren't indicators of poor maintenance...they happen the moment you turn the key...it's silly to leave any more of them in the engine than absolutely necessary come OCI, wouldn't you agree ?

And while we are there, one of the SAE papers that I linked to shows that dispersent incompatibility caused agglomeration of the previously dispersed soot...makes big "filterable" particles, but is overall a bad thing.

 

[alarmguy]

To me, the advice that hurts the most amount of ego's in here is the following advice ...

Anyone considering an oil will be just as well off selecting ANY oil brand they want that carries the TRUE API Donut or ACEA certification and weight suggested in the owners manual. It doesnt matter conventional or synthetic as long as whatever you are using is the proper oil stated in the owners manual.
Everything else is marketing (with some exceptions) and almost everything else lacks real tests and facts.

Bottom line, its the engine design not the oil that decides how long and well your engine will run.
A properly designed engine should outlast the usefulness of rest of the vehicle when using the recommended oil.
We do choose oils sometimes in our mind that in reality is to make up for the lack of proper engine design by the manufacturer.

I will admit, even though I could care less (for the most part) what oil filter I use, I do believe in magnetic plugs as their filtering capacity is almost limitless down to the smallest micron and just the fact that some vehicle makers go the extra mile and use them says something to me.

 

[Shannow]

^...well said.

 

[ZeeOSix]

Originally Posted By: Shannow
There's plenty of stuff that's held up in circulating oil by the dispersents that aren't filterable...e.g. soot in a UOA is clearly not filterable, it hangs around, and builds up to whole numbers of percents. Needs the agitation and flow to keep it moving, or it slowly settles out, to be re circulated next time the thing is run...

Varnish a sludge precursor is also far less soluble in cold oil than hot...and when hot, is clearly not filterable.

So leaving a sump to cool gives you the "best" of both worlds...varnish isn't soluble, and starts to drop out. Soot and the like drop out.

And at the bottom of the sump, form a more viscous semi solid natured paste, that WON'T drain out if you pull the plug...it will sit there until you warm the engine up again, then get either re-dissolved (varnish) or picked up and circulated (soot and the like)...bingo, your brand new oil is dirty again...

Drain it hot, the soot is still dispersed, the varnish is still dissolved, and physically more of the total volume comes out the drain plug...thus manufacturer's recommendations.

Absence of the paste of settled varnish and soot means that heavy particles rather than getting "stuck in the mud" have an opportunity to flow out as well.

And no, varnish and soot aren't indicators of poor maintenance...they happen the moment you turn the key...it's silly to leave any more of them in the engine than absolutely necessary come OCI, wouldn't you agree ?


I could see where draining a diesel hot vs cold compared to a gas engine would make more of a difference due to the soot. Gas engines have way less suspended particulate and insolubles.

I'd like to see some more examples and photos from a controlled experiment like what 02SE mentioned to prove that draining cold leaves nasty debris behind in the sump on a well maintained clean engine. Where's the SAE paper Shannow?

And yeah, of course I agree that draining hot is probably better than cold in the long run, but draining cold isn't gonna smoke your engine, just like using an inefficient oil filter isn't gonna smoke your engine vs a super efficient oil filter which does a better job keeping the oil clean. That's a whole other debate that happens all the time in the oil filter forum.

 

[Shannow]

Originally Posted By: ZeeOSix
And yeah, of course I agree that draining hot is probably better than cold in the long run, but draining cold isn't gonna smoke your engine, just like using an inefficient oil filter isn't gonna instantly smoke your engine vs a super efficient oil filter. That's a whole other debate that happens all the time in the oil filter forum.


And the circle turns to the old "nothing is likely to blow up standard"...which got me posting this thread in the first place...

 

[Ducked]

Originally Posted By: ZeeOSix


How did you know it did?
[Put metal in the drained oil, I think]

Er...because there was metal in the drained oil. It settled out very slowly, and also formed a thin slurry over a magnetic pickup tool left in the oil.

Originally Posted By: ZeeOSix
I'm not doubting what you're saying, but obviously this car was owned by someone else and you have no exact knowledge of how it was treated or maintained.


They showed me a huge pile of service records from a Daihatsu main dealer in Kaoshiung, which I forgot to collect. Later I emailed them (wanted to try and find out when the timing belt was changed) and they sent me a few scans which I had translated. COULD have been an elaborate scam, but not likely for a 300 quid car.

Originally Posted By: ZeeOSix
If he claims it was always "dealer maintained" then the oil was probably always drained hot,


Don't see that. Never had anything done by a dealer, but I imagine you might drop your car off and it might get done when they get around to it.

Originally Posted By: ZeeOSix
so if you think having debris in the sump is from draining the oil when cold then you're way off track.


Nope. I think IF you've got debris in your sump (and I'd think there will often be some) then draining it cold isn't the best way to get rid of it, which is where we came in.

Anyway, I don't especially want to attack your belief system. Do what you like.

Here's the original thread on this metal.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/2976159/Deposit_on_Dipstick#Post2976159

My best guess is its from the cam lobes, which might have lost case-hardening, but of course I don't know.

 

[userfriendly]

I'm not willing to trade engine wear for fuel economy. For example, a new pick up truck pushing $70k isn't getting 0W20 from me for a 2% fuel saving.
I believe that an engine that burns oil when new, will eventually end up with issues like sticking rings and worse fuel economy down the road.
My target is 20 years or 500K miles which ever comes first, without getting into the engine. In fact, I'm starting to think that light weight automatic transmission fluids
like Dexron VI may be good for fuel economy, but bad in the long run for longevity.

If it is true that most engine wear occurs during warm-up, then a heavier grade that still meets the cold start requirements will activate the engine oil's AW additives sooner,
because the oil warms up faster from fluid friction.

edit; I drain engine oil hot and have the burns to prove it.

 

[ZeeOSix]

Originally Posted By: Shannow
Originally Posted By: ZeeOSix
And yeah, of course I agree that draining hot is probably better than cold in the long run, but draining cold isn't gonna smoke your engine, just like using an inefficient oil filter isn't gonna instantly smoke your engine vs a super efficient oil filter. That's a whole other debate that happens all the time in the oil filter forum.


And the circle turns to the old "nothing is likely to blow up standard"...which got me posting this thread in the first place...


Well, then show some data then that proves draining the oil cold will reduce the life (increase wear) of an engine compared to draining it hot. Sounds like a good topic for an SAE paper.

When someone can prove that phenomenon exists then it makes a difference ... if not, then it's all conjecture.

 

[alarmguy]

Originally Posted By: Shannow
^...well said.


Thank you .. ... and off to work I go...

 

[ZeeOSix]

Originally Posted By: Ducked
Originally Posted By: ZeeOSix
so if you think having debris in the sump is from draining the oil when cold then you're way off track.


Nope. I think IF you've got debris in your sump (and I'd think there will often be some) then draining it cold isn't the best way to get rid of it, which is where we came in.

Anyway, I don't especially want to attack your belief system. Do what you like.

Here's the original thread on this metal.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/2976159/Deposit_on_Dipstick#Post2976159

My best guess is its from the cam lobes, which might have lost case-hardening, but of course I don't know.


Your engine is producing abnormal amounts of Fe particles as you've proven - maybe some non-Fe particulate too. They are large enough to probably fall to the bottom of the oil pan while the engine is running. In your case I highly doubt draining the oil hot or cold is going to change anything - especially since your oil pan isn't flat and smooth, and looks like there's a raised area inside the pan where the drain plug threads into, so heavy particles won't get past that point.

And I'll ask again ... have you cut open any oil filters off this car to inspect for caught particles? If so, what did you find? If not, you should.

 

[Ducked]

Originally Posted By: alarmguy
To me, the advice that hurts the most amount of ego's in here is the following advice ...

Anyone considering an oil will be just as well off selecting ANY oil brand they want that carries the TRUE API Donut or ACEA certification and weight suggested in the owners manual. It doesnt matter conventional or synthetic as long as whatever you are using is the proper oil stated in the owners manual.
Everything else is marketing (with some exceptions) and almost everything else lacks real tests and facts.





Ok, call me an egomaniac, but I'm not using the specified oil (10W30) which I've never seen here. I'm using Delvac MX 15W40 (which doesn't carry the API donut either) and I doubt I'm doing any harm thereby.

Its an mouldy oldy, of course, but in the US OEM specs are partly driven by fleet fuel economy targets and may not be optimal for a given vehicle.

Originally Posted By: alarmguy

I will admit, even though I could care less (for the most part) what oil filter I use, I do believe in magnetic plugs as their filtering capacity is almost limitless down to the smallest micron and just the fact that some vehicle makers go the extra mile and use them says something to me.


Also disagree about mag drain plugs, though I have one. They do not have "limitless capacity". They have very limited capacity, though they have no lower limit on ferrous particle size trapped. If you want significant capacity you probably have to go for a bandolier round the oil filter, though I'm not sure that magnetised wear particles are necessarily a good thing in an engine.

 

[Ducked]

Originally Posted By: ZeeOSix


And I'll ask again ... have you cut open any oil filters off this car to inspect for caught particles? If so, what did you find? If not, you should.


No, I kept a filter or two but had to chuck them away (with a lot of other stuff) when downsizing my accommodation.

In general, based on what I've seen on here, this seems likely to be a messy waste of time, especially bearing in mind that I have no workshop/shed etc to do this kind of thing in.

In this specific situation it might have been a bit informative, but wasn't really a priority.

 

[Shannow]

Originally Posted By: ZeeOSix
http://www.cartalk.com/content/which-better-changing-your-oil-when-engine-hot-or-cold

http://www.cumminsforum.com/forum/general-diesel-discussion/393160-oil-drain-hot-cold.html

All kinds of talk of draining the oil hot or cold.
https://www.google.com/?gws_rd=ssl#q=draining+oil+when+cold


All kinds of talk, including a poll on "why I don't follow Cummins' advice", including "don't want to burn myself", to misinformed comments like "it's all in the pan and drains out anyway" (which we've been over, and is clearly false.

So I provide manufacturer's recommendations from their manuals, and you counter with "talk" from various chats boards...sound basis for a position, not.

 

[ZeeOSix]

^^^ No ... it sounds controversial, just like many other discussed topics. And as you can see in many of the internet discussions that the population is about spit 50/50 on draining hot vs cold.

So dig up at least one legitimate paper (SAE preferred) that prove that draining the oil cold causes more engine wear or any other detrimental effects compared to draining the oil hot.