Varnish: What's the downside?

Thanks for the comedy, I'm just talking about an engine flush product that isn't ATF and/or one of the fine backyard concoctions that members come up with here.
So you don’t see the issue in dumping something that’s not even a lubricant into your engine? How does this differ from the people who are willing to dump ATF or kerosene into their crankcase? None of them are engine oils either… how are you even able to verify that an engine flush is “flushing”? What are the measurable results?
 
So you don’t see the issue in dumping something that’s not even a lubricant into your engine? How does this differ from the people who are willing to dump ATF or kerosene into their crankcase? None of them are engine oils either… how are you even able to verify that an engine flush is “flushing”? What are the measurable results?
Seems you are just fishing, you should probably do some better research about the facts of the products in question.
 
I'm just fascinated that flushes are allegedly SOP with oil changes in AU. I'm not aware of anyplace in the States that would consider this to be the case.

I'm not saying "we" are better or smarter -- I just find these cultural or geographical differences very interesting.
 
Seems you are just fishing, you should probably do some better research about the facts of the products in question.
Im not fishing… you’re the one who came in here proclaiming the “incredible benefits” of engine flushes, when several senior mechanics and even an oil manufacturer have commented that engine flushes aren’t needed and can cause harm… so the ball’s in your court. I already staked my claim on oils that include esters and ANs, which are shown by multiple studies in multiple industries that these are the proper way to keep engines clean and to clean ones with previous deposits.
 
I'm just fascinated that flushes are allegedly SOP with oil changes in AU. I'm not aware of anyplace in the States that would consider this to be the case.

I'm not saying "we" are better or smarter -- I just find these cultural or geographical differences very interesting
Yes it is most of the motoring public here have no issues with engine flushes its not a 'thing' like in the US it seems.



 
Im not fishing… you’re the one who came in here proclaiming the “incredible benefits” of engine flushes, when several senior mechanics and even an oil manufacturer have commented that engine flushes aren’t needed and can cause harm… so the ball’s in your court. I already staked my claim on oils that include esters and ANs, which are shown by multiple studies in multiple industries that these are the proper way to keep engines clean and to clean ones with previous deposits.
Sorry, I didn't mean to upset you with a different view. I don't think I made any 'incredible benefit' statements.
 
Sorry, I didn't mean to upset you with a different view.
I’m not upset at all, and I’m fine with different views. But the general idea is when you make a claim, that you have something to back it up with, other than “I poured it in and the engine didn’t blow up”, that’s all.✌️

In this case, there are fully-formulated oils which will not only do a more thorough cleaning than any 5-minute flush, but also do it without ever risking your engine in the process.
 
If the car has been maintained perfectly from its 1st service and using quality oil, a flush may not be needed. Now I understand that is the majority of people on this forum. However, a less well maintained car will suffer from things such as varnish/sludge etc especially when using less than top tier oils or various oils over extended OCI etc.

If the car has passed through many owners it will more often than not suffer from some of these issues.
Yes, that's what we are discussing, engines that may have some deposits inside. What I'm looking for is a technical reason why one would choose to use a flush instead of a more gentle cleaning product, like an oil with AN's and/or esters.
I live in Australia and it is very common here for mechanics to use quality engine flushes at every oil change. More likely than not the engine will benefit from this type of cleaning. Also it causes no issues to modern engines that 'may' not need it.
Yes, I picked up on the fact that this appears to be very common where you live. It's not very common here. As I noted above, I'm looking for a technical reason; a justification on why one would use a flush product, which goes against the advice given by probably every OEM on the planet, versus just using an oil that can clean, something they don't advise against. I'm also sceptical of the very universal claim that "more likely than not the engine will benefit from this type of cleaning", as that seems more like a sales pitch rather than a fact supported by amassed statistical data.
I will direct you to the Valvoline engine flush for further information. If you do not wish to use engine flush that is fine you most likely don't need to because you maintain and buy top tier products for your vehicle. However, I have run hundreds of flushes through customers cars and never once had an issue. Moreover, some of the benefits I have seen have been excellent especially in regard to its commercial purpose (see below).

Can you expand on this?

I assume you are aware that the manual for most vehicles has a blurb such as this one in it?
Screen Shot 2023-01-07 at 11.28.23 AM.jpg


What do you think you'd see if you DID have an issue? That is, if you were negatively impacting the existing AW chemistry laid down or slightly accelerating wear, how do you think that would be evidenced? How would it present?

On the benefits, can you expand on this? Are we talking an increase in compression, reduction in oil consumption...etc?

I appreciate your engagement thus far.

As an aside, at this juncture, I am still of the impression that these are a money making scheme. The fact that Valvoline makes one doesn't change that, Liqui-Moly does, AMSOIL does, plenty of the smaller guys make and market additives that have questionable value.
 
That in no way answers the question (nor did you bother to address the rest of my rather lengthy post). That's somebody's college paper testing varnish removal on a rig that simulates a gas turbine:
The current test rig is designed to test artificial varnish adhered to steel coupons formulated to mimic gas turbine engine varnish.
A number of chemical cleaners are commercially available which claim to remove varnish from equipment such as turbines and compressors. [74,75] Evaluating the effectiveness and efficiency of different chemical cleaners is challenging because there is currently no standard test method for quantifying varnish removal that enables direct comparison.

It also makes no mention of other methods (such as using an oil formulated for this purpose), only mentioning electrostatic removal as an alternative to chemicals.

To be clear here: You are the one that made the claim about the utility of flushes (and seem totally unfazed by the fact that OEM's essentially universally condemn their use), the onus is on you to support that claim, not on me to perform that research.
 
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That in no way answers the question (nor did you bother to address the rest of my rather lengthy post). That's somebody's college paper testing varnish removal on a rig that simulates a gas turbine:



It also makes no mention of other methods (such as using an oil formulated for this purpose), only mentioning electrostatic removal as an alternative to chemicals.

To be clear here: You are the one that made the claim about the utility of flushes, the onus is on you to support the claim, not on me to perform that research.
Haha there is no onus. Feel free to research I have provided some good material. I don't think you will ever use an engine flush no matter what I put up here, but I respect that.

And stop cherry picking:

'Varnish can be detrimental to the performance of mechanical systems. Our research aims to characterize the removal of this varnish film to optimize system efficiency. The research in this paper provides information crucial to the selection of a commercial chemical cleaner and how to use them properly, such as not recycling fluid. The improvements to the test rig will allow for a more comparable testing to what might actually be seen in a chemical flushing environment'.
 
Haha there is no onus.
I mean, there is if you want others to ascribe any merit to the claim you've made. If you don't, that's fine, but then I'd expect regular pushback on this subject in the future as a result of that decision.
Feel free to research I have provided some good material.
Again, that's not my responsibility, I'm not the one who has made the claim here with respect to the merit of flushes, you are.
I don't think you will ever use an engine flush no matter what I put up here, but I respect that.
Quite likely. I simply fail the see the utility of them, I see them as a money grab and you've presented nothing that has made any inroads into swaying my position on that.
And stop cherry picking:

'Varnish can be detrimental to the performance of mechanical systems. Our research aims to characterize the removal of this varnish film to optimize system efficiency. The research in this paper provides information crucial to the selection of a commercial chemical cleaner and how to use them properly, such as not recycling fluid. The improvements to the test rig will allow for a more comparable testing to what might actually be seen in a chemical flushing environment'.
It's not a cherry pick, the testing in that college paper was designed around turbines and compressors, per the sections I quoted. The overarching observation that varnish formation extends beyond that scope; beyond the scope of the test mechanism, doesn't change the nature of the test.

Of course since this was a bench test designed to gauge efficacy of varnish removal, not evaluate systems-level impact, little consideration was given to the results of the chemical removal mechanism beyond the passing mention of large chunks being liberated by one of the cleaners that blocked the filter.

Since, as noted, there is no regulation with respect to these flushes, their impact, safety, and effectiveness isn't formally qualified by any overseeing body. This makes them risky, which is why OEM's make the statements in their manuals telling people not to use them, like I provided an example of.

I have no problem with people spending their own money on things of questionable value like flushes, that's their business. I do however take issue with people trying to spend other people's money on these products. If you recommend something and claim feats of excellence, I think it's quite reasonable to be expected to back those claims up.

If you haven't read the HPL engine cleaner thread, I'd highly recommend it:

Also, if you search for "flush" and user @MolaKule (an experienced formulator) you will find this post, amongst others:
MolaKule said:
"Flashoff" is a misnomer. The solvents don't instantly or magically disappear at some elevated temperature. In a carrier oil, they take longer to evaporate at this elevated temperature.

But in my view, the whole purpose of a flush is to solve the excess hydrocarbons quickly, evaporate the volatile solvents, and then leave the excess hydrocarbons to be suspended in the bulk oil and filter; hence a drain and filter change immediately after the flush.

Again, my preference is to slowly 'solve' the hydrocarbons with an engine cleaner containing a special cleaning ester (with an appropriate DI package) that then suspends the soft liquified (not chunky) deposits in the bulk oil and filter.

Please notice that few, if any of the flushes, contain a DI package to supplement the chemistry that it displaces. Any flush, without a supplemental DI package, will reduce the performance and protection chemistry of the bulk oil.

Which mirrors my position on the matter.
 
Varnish is a good thing. It's a in your face that either your maintenance method and or product isn't up to the job. We've found out that running an engine cleaner like EC30 from HPL can get some of this to go away. Running a high ester content oil can do the same. If I see high varnish I simply say that it needs more care. Better oil, fuel,filters,etc but also probably needs to have the emissions system inspected too. How's the pcv valve,egr and so on. Get those cars on the freeway with the pedal to the metal or at least aggressively push them into the higher RPM when can safely be done.
 
I mean, there is if you want others to ascribe any merit to the claim you've made. If you don't, that's fine, but then I'd expect regular pushback on this subject in the future as a result of that decision.

Again, that's not my responsibility, I'm not the one who has made the claim here with respect to the merit of flushes, you are.

Quite likely. I simply fail the see the utility of them, I see them as a money grab and you've presented nothing that has made any inroads into swaying my position on that.

It's not a cherry pick, the testing in that college paper was designed around turbines and compressors, per the sections I quoted. The overarching observation that varnish formation extends beyond that scope; beyond the scope of the test mechanism, doesn't change the nature of the test.

Of course since this was a bench test designed to gauge efficacy of varnish removal, not evaluate systems-level impact, little consideration was given to the results of the chemical removal mechanism beyond the passing mention of large chunks being liberated by one of the cleaners that blocked the filter.

Since, as noted, there is no regulation with respect to these flushes, their impact, safety, and effectiveness isn't formally qualified by any overseeing body. This makes them risky, which is why OEM's make the statements in their manuals telling people not to use them, like I provided an example of.

I have no problem with people spending their own money on things of questionable value like flushes, that's their business. I do however take issue with people trying to spend other people's money on these products. If you recommend something and claim feats of excellence, I think it's quite reasonable to be expected to back those claims up.

If you haven't read the HPL engine cleaner thread, I'd highly recommend it:

Also, if you search for "flush" and user @MolaKule (an experienced formulator) you will find this post, amongst others:


Which mirrors my position on the matter.
Feel free to research I have provided some good material. I don't think you will ever use an engine flush no matter what I put up here, but I respect that. If you actually do want some more data etc you could call Valvoline or Amsoil for verification because it seems you are only interested in data I have recorded for the efficiency of the products.

You have given me your opinion and I have given mine.
 
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I mean, there is if you want others to ascribe any merit to the claim you've made. If you don't, that's fine, but then I'd expect regular pushback on this subject in the future as a result of that decision.

Again, that's not my responsibility, I'm not the one who has made the claim here with respect to the merit of flushes, you are.

Quite likely. I simply fail the see the utility of them, I see them as a money grab and you've presented nothing that has made any inroads into swaying my position on that.

It's not a cherry pick, the testing in that college paper was designed around turbines and compressors, per the sections I quoted. The overarching observation that varnish formation extends beyond that scope; beyond the scope of the test mechanism, doesn't change the nature of the test.

Of course since this was a bench test designed to gauge efficacy of varnish removal, not evaluate systems-level impact, little consideration was given to the results of the chemical removal mechanism beyond the passing mention of large chunks being liberated by one of the cleaners that blocked the filter.

Since, as noted, there is no regulation with respect to these flushes, their impact, safety, and effectiveness isn't formally qualified by any overseeing body. This makes them risky, which is why OEM's make the statements in their manuals telling people not to use them, like I provided an example of.

I have no problem with people spending their own money on things of questionable value like flushes, that's their business. I do however take issue with people trying to spend other people's money on these products. If you recommend something and claim feats of excellence, I think it's quite reasonable to be expected to back those claims up.

If you haven't read the HPL engine cleaner thread, I'd highly recommend it:

Also, if you search for "flush" and user @MolaKule (an experienced formulator) you will find this post, amongst others:


Which mirrors my position on the matter.
O/K, it’s obvious he has no intent nor capability of providing any scientific proof to support his baseless claims.
 
O/K, it’s obvious he has no intent nor capability of providing any scientific proof to support his baseless claims.
At what stage am I required to produce evidence for my claims. The claims are made on the bottle and within my links etc. I am not an authority and neither are any of you. We can sit here and pretend to critically review evidence on an oil forum lol, when their is no authority here. If you wish to have a better understanding of the products you should seek to find out through the manufacturers.

We have given our opinions and that is all. You cant reference forum material as academic etc. You need to go to the source. You also have to be a professional in that specific field before you pretend their is any meaning in critically analysing my 'opinions' which are based on the product itself. Also, there needs to be no bias, so we can write off any professionals with a 'opinion' here. Anyone can spin a angle and be be backed up by people who have no idea on any of the things I have just brought up.

Its been 'overkilled' the whole thing. Its absurd. Its a forum I was giving my opinion. No one here can give more than that. You are just alienating other members and destroying a good thread.
 
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At what stage am I required to produce evidence for my claims. The claims are made on the bottle. I am not an authority and neither are any of you. We can sit here and pretend to critically review evidence on an oil forum lol, when their is no authority here. If you wish to have a better understanding of the products you should seek to find out through the manufacturers.

We have given our opinions and that is all. You cant reference forum material as academic etc. You need to go to the source. You also have to be a professional in that specific field before you pretend their is any meaning in critically analysing my 'opinions' which are based on the product itself. Also, there needs to be no bias, so we can write off any professionals with a 'opinion' here. Anyone can spin a angle and be be backed up by people who have no idea on any of the things I have brought up here.

Its been 'overkilled' the whole thing. Its absurd. Its a forum I was giving my opinion. No one here can give more than that.
You’ve been given numerous non-opinion pieces of evidence that flushes are questionable at the very best; vehicle manufacturers, oil manufacturers, chemical experts that have worked in industry for decades, of which the latter two groups have posted at various times on this board numerous times stating that fully-formulated oils that meet the engine’s requirements is all that should ever be placed in an engine’s crankcase.

The only thing this board has never seen is a post by any of these three groups promoting, condoning, or even confirming the viability of engine flushes, let alone their use. I’ll agree with you that all posts regarding flushes’ benefits have only ever been opinions, and restate the fact that the anecdotal evidence of having poured an engine flush into one’s crankcase and the engine didn’t blow up is not evidence of a benefit.

Discussing varnish removal in turbines does not directly correlate to an internal combustion engine, nor does it recognize the fact that varnish removal or other cleaning is best executed with oil components that are designed to clean while being part of the fully-formulated oil where it can be carefully controlled, not something a user arbitrarily dumps in. You’re certainly free to have your own opinion, but that doesn’t mean it has any basis in fact or science.

Heck, even with all the discussions that a certain member has to justify his position on extremely thin oils have reference papers from accepted industry whitepapers which then have the user’s opinion have much more discussion value than “oil flushes must be fine because many companies make & sell them!!” You’ve heard of PT Barnum and his marketing methods, right?
 
You need to go to the source. You also have to be a professional in that specific field before you pretend their is any meaning in critically analysing my 'opinions' which are based on the product itself. Also, there needs to be no bias, so we can write off any professionals with a 'opinion' here.
That is preposterous. So @High Performance Lubricants, @MolaKule, @Tom NJ, Solarant, Bruce...etc are all written off by you (your words) because they participate on this forum. The fact that they are unbiased (none of them produce or sell flushes) makes them unqualified to speak on the subject? I'm speechless, I cannot believe what you've written here, absolutely unreal.
Its been 'overkilled' the whole thing. Its absurd. Its a forum I was giving my opinion. No one here can give more than that.
I mean, they can, there are several experts who participate here, I quoted one of them. However, you noted that your position is to write off their opinion because they participate here (this is a beautiful paradox, appeal to authority and then dismiss said authority because it participates within the medium that the appeal was made). If we are calling out things that are absurd, this truly takes the cake.
 
That is preposterous. So @High Performance Lubricants, @MolaKule, @Tom NJ, Solarant, Bruce...etc are all written off by you (your words) because they participate on this forum. The fact that they are unbiased (none of them produce or sell flushes) makes them unqualified to speak on the subject? I'm speechless, I cannot believe what you've written here, absolutely unreal.

I mean, they can, there are several experts who participate here, I quoted one of them. However, you noted that your position is to write off their opinion because they participate here (this is a beautiful paradox, appeal to authority and then dismiss said authority because it participates within the medium that the appeal was made). If we are calling out things that are absurd, this truly takes the cake.
Its not up to me to provide evidence. You are saying their is no evidence to support flushes because 3 professionals agree with you. What about the professionals who are pro flush and manufacture the chemicals have you considered them. You can just deny them because you only want to make a point. You don't wish to learn anything because you have found you feel comfortable with 3 professional answers that support your viewpoint and all on one forum that you personally know. Surely, you have proved you have critical thinking skills but still you cant comprehend that aspect of it. Lots of 'experts' say the world is flat too. But other experts say it isn't. You are leaving the core concept of critical thinking off the desk.
 
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