Engine oil flush treatments.

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Hi Gents
Did a search but found nothing much, so sincere apologies if this is 'old ground'.

Engine oil, pre change flush chemicals such as, https://products.liqui-moly.com/engine-flush-plus-3.html, for example. They use words and phrases like 'removes troublesome deposits', 'sludge' and 'lacquers'. Words to frighten the layperson.

Are they a useful 'tool' that will help keep your engine in tip top condition?

OR

Total waste of money and of no benefit in a correctly maintained engine, one that has oil changes done at the recommended intervals, using quality Oil of the correct specification.

My unqualified take on this is as follows. If an engine has 'troublesome deposits', 'sludge' and 'lacquers' then your Oil change regime is wrong. Use better oil and change more frequently.

Difference maybe in Gas or Diesel engines?

That may well be a gross over simplification so I would appreciate some opinions Gents please

Many thanks

Tikka.
 
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There are plenty of engines that have had the best oil and frequent changes that are sludged deposited... but mostly from manufacturing defects such as poorly designed PCV and also defective rings.
 
I've used those treatments before on used vehicles I have bought. There were no signs of neglect. Given what I've learned here, I wouldn't bother using them.

Are you trying to fix a problem motor?
 
Hi
I have no problems that I am aware of on my OM642 Merc' unit. But then I have not got x-ray vision
smile.gif


As I am about to perform an oil and filter change I wondered if these pre change flushes had anything solid to offer. I note that a lot of garages offer them but I just presume they look on it as a money spinner. I am always the cynic.

Tikka.
 
Kreen is probably the strongest internal cleaner, and like $16/quart, which is enough for two treatments. Search for a thread on it by Trav, lots of great info there. But, unless you can look through the fill hole or remove the valve cover and see there are issues, it's probably not necessary. Another, more costly option would be to run the Valvoline Premium Restore (search for a thread by JAG on it), which is specially formulated to clean and free up ring lands and other areas. But it's $74/gallon.
 
Originally Posted by Tikka
Hi
I have no problems that I am aware of on my OM642 Merc' unit. But then I have not got x-ray vision
smile.gif


As I am about to perform an oil and filter change I wondered if these pre change flushes had anything solid to offer. I note that a lot of garages offer them but I just presume they look on it as a money spinner. I am always the cynic.

Tikka.


Of course they want to flush your wallet with needless services. Some people use kerosene to flush the motor as well. Lots of these flushes are made up of kerosene.

If you cannot open up the motor to have a look cut open the oil filter and see if anything was caught in the pleats.
 
Originally Posted by JC1

Of course they want to flush your wallet with needless services. Some people use kerosene to flush the motor as well. Lots of these flushes are made up of kerosene.


A guy I knew bought a can of "engine flush" (it was 100% metal can) ............. "name brand" stuff

He opened it, and it was just a quart/liter of Red Diesel fuel. Nothing different at all about it - just plain red diesel.
 
I use engine flush products around 100,000 miles. If your engine design has known problems with blow-by, sludging or deposits, more often would be a good idea. Or just get a better vehicle that has no issues with the engine design.
 
Originally Posted by Linctex

He opened it, and it was just a quart/liter of Red Diesel fuel. Nothing different at all about it - just plain red diesel.


A question on an engine with minor sludging issues would you
After draining oil for an oil change dump a small amount of virgin off spec motor oil through the top load filter and oil fill point to clear some more of the sludge?

I have inherited many bottles of antique oil from the 80's I can't use along with mmo and figure I could dump it in once the drain is nearly over and get more gunk out.

I tried it and it seems to at least cosmetically get the filter housing clean and it does appear to drain out after a while.
Only takes a couple ounces to clean out, just not sure to what degree it ends up basically stuck in the engine and apart of my fill or not.
 
Originally Posted by Rmay635703

A question on an engine with minor sludging issues would you
After draining oil for an oil change dump a small amount of virgin off spec motor oil through the top load filter and oil fill point to clear some more of the sludge?


I do a similar procedure on my project 4Runner which was neglected by the original owner. Oil drain plug is on the driver's side bottom of the sump, dipstick is on the passenger side of the engine. I put the vehicle passenger side front & rear on ramps to tilt it toward the drain plug. After draining the oil, I pump around 1/2 quart of Supertech oil down the dipstick hole...it washes across the oil sump and pushes out sludge that would otherwise have stayed in the sump as shown in the attached pics. I put a clean paper towel across the drain funnel after the drain, and then pumped oil down the dipstick tube, this crap came out.

IMG_2299.JPG


IMG_2300.JPG


IMG_2303.JPG
 
I've been told by old mechanics to add a quart of ATF 10-15 miles before an oil change. I've done it to flush engines before with relatively new oil still light brown and after 10 miles with ATF it is black.
 
Originally Posted by Danr42
I've been told by old mechanics to add a quart of ATF 10-15 miles before an oil change. I've done it to flush engines before with relatively new oil still light brown and after 10 miles with ATF it is black.


Atf has little detergents, little cleaning ability. It only thins out your oil and dilutes the add-pack. I would not use that.
 
Originally Posted by Danr42
I've been told by old mechanics to add a quart of ATF 10-15 miles before an oil change. I've done it to flush engines before with relatively new oil still light brown and after 10 miles with ATF it is black.

Not a good idea, as mentioned above.
 
Originally Posted by Danr42
I've been told by old mechanics to add a quart of ATF 10-15 miles before an oil change. I've done it to flush engines before with relatively new oil still light brown and after 10 miles with ATF it is black.

Also please don't randomly resurrect old threads just to post incorrect information.
 
I have a can of LM Proline engine flush...will use at some point. Can't hurt.
 
Originally Posted by Danr42
I've been told by old mechanics to add a quart of ATF 10-15 miles before an oil change. I've done it to flush engines before with relatively new oil still light brown and after 10 miles with ATF it is black.


As others have stated ATF is not a proper flush and has little detergency:

Originally Posted by MolaKule
I guess some people don't read other threads on this topic but here goes (Ron Ananian not withstanding):

First of all, I think we can agree that ATF is a "thin" fluid. Thin fluids are better able to flush dirt and sludge. In addition back then, ATF's had high values of detergency, and in many cases, more than motor oils.

BTW, detergency does not mean it has to have high calcium, sodium, magnesium or whatever values. Detergency can mean it has solvency from other compounds. For example, Pennzoil uses PEG's for dirt and sludge precursor solvency.

In the earlier days, ATF's such as Type A had a percentage of Naphthenic base oil, with a bit of sperm whale oil (a naturally occuring ester used for friction modification) and mostly mineral oil.

Now both Naphthenic base oils and the sperm whale oils have solvent action.

Today, motor oils have more detergency than ATF's, because ATF's are mostly non-polar GroupIII and PAO, with a smidgeon of "not-so-solvent" POE's.

About the only detergent/dispersant one sees today in ATF's are the multi-functional calcium additives at about 150 ppm, which is 20 times lower than what you see in motor oils. Those multi-functional calcium additives also act as rust preventers. In addition, most ATF's have only about 300 PPM of phos AW additives. Engine oils have about 2.5 times that amount.

My advice is if you have an indication of sludging, use something like ProTec or Rislone Engine Treatment and use it as a FLUSH.Â

A FLUSH is a batch of solvent chemicals added to the oil such that the engine is brought up to operating temperature at idle and then the whole schmear is thoroughly drained, with new oil and filter added afterwords. Do not drive with a Flush.
 
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IMO, products like these fall into two categories with their own sub-categories.

A: Doesn't harm the engine.
1. Do nothing.
2. Work as advertised.

OR

B: Harms the engine.
1. Do nothing
2. Work as advertised

The vast majority of products fall under A but it's almost impossible for the consumer to know whether or not it was effective, my guess is more often than not they fall under A1 (MMO/Seafoam...cough cough). Just because a product doesn't hurt your engine doesn't mean it works as advertised.

This Liqui Moly product has been around for years as some form or another. I doubt it would damage an engine, HOWEVER, it could remove deposits which themselves were preventing a gasket from leaking. Some consumers may consider that as engine harm, when in reality it just revealed a bad gasket which harms your wallet.

I think there's a YouTube video or a customer review (Amazon US) where somebody drained and refilled with cheap oil just to add the LM engine flush. They then drained that oil and compared to a sample of the clean oil w/out the engine flush. IIRC the oil with the engine flush came out considerably darker than the clean oil which would lead one to believe that it does "work".
 
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Use a High Mileage oil heavy on Alkylated Naphthalene base-stocks, and do a 3k cleanup OCI. 2 birds one stone.
 
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