Engine flush?
- Thread starter Bettez88
- Start date
I just wanted to make a 2 cent deposit here on behalf of the very well known Daniel Stern who is quite the auto guru in many areas since he has worked directly with o.e. engineers & is also known in the Automotive engineering world & consulting mostly with o.e lighting & lighting laws for N.America. Daniel Stern Lightning Conlsutant.
He write on a few forums as SlantSixDan, on ForABodiesOnly & SlantSix Forums in is very well respected.
Here is his Engine Flush Elixir.
https://www.slantsix.org/forum/viewtopic.php?t=11432&start=15
SlantSixDan Daniel Stern Engine Flush Procedure:
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"Careful-careful-careful. Those "engine flush" compounds you can find at the auto parts store can do a tremendous amount of damage.
I have long maintained that your engine is not a toilet (Chevrolet Vega, Cadillac HT4100 and V8-6-4, and Ford 3.0 owners excepted) and therefore does not need flushing except under specific and rare conditions as a corrective measure. Everyone's got a pet theory on how best to flush a crudded-up engine without pulling the pan. Some methods are harmless but ineffective. Some methods are potentially harmful. Some methods are harmless and effective. For best results, pick one of that last kind.
I do not believe there is any such thing as a safe, effective and fast engine flush procedure. You can pick any two of these three: Safe and effective (but not fast), safe and fast (but not effective), effective and fast (but not safe). The risks fall into two categories:
which is a specialized solvent that's very good at one particular task: Cleaning the mayonnaise out of a crankcase that's had coolant in it due to a faulty head (etc.) gasket. Their use in any other situation is risky.
My own engine flush recipe is a delicious blend of Marvel Mystery Oil (very light weight and good at dissolving gums and sludges), Kroil (best penetrant on the planet), ATF (detergent/dispersant with good lubricity), and Berryman B12 ChemTool (good at dissolving crud too tough for Marvel Mystery Oil).
My procedure involves warming up the engine, draining the oil, changing the oil filter, replacing the drain plug (!), and pouring in the soup. For a 5-quart crankcase, I usually start with 1/1/2/1 (Marvel/Kroil/ATF/B12). Then start and run the engine in the driveway at around 1200 to 1700 RPM with no sudden acceleration and no load applied, for 15 minutes.
Shut down, drain (really let it drain, walk away for 45 minutes), change the filter again, repeat with new soup for 30 to 45 minutes depending how gross the first batch of soup was when it was drained and how quickly the second batch of soup cruds up. Check the dipstick periodically.
If the 2nd batch of soup comes out coalmine black and full of chunks, run in another batch of soup (and another new filter!) and repeat until chips, chunks and tar stop coming out when you drain it. Then it will also be a good idea to service the oil pressure relief valve to make sure it's doing its job, as described in these two threads: thread 1, thread 2.
You'll note the filter is replaced before any attempt is made to introduce a flushing agent into the crankcase, and the filter is replaced again every time you drain a batch of flushing soup. Without doing this, you run the very real risk of inundating the filter, which will go into bypass mode and send all the loosened-up crud directly to the bearings and other critical parts: Goodbye, engine, it was nice gnawing you.
I've gotten amazing amounts of corruption and trash out of engines using this recipe and method. Other methods and other recipes may work better
for other people with other cars. The Kroil people (Kano Labs) have an engine cleanout "soup" of their own they call Kreen; I've had great results with pretty much every one of their products I ever tried, but I don't have enough direct experience with Kreen to comment. And as always, be advised that if the engine is really tired and whipped, even a safe flush can cause additional problems in the form of "new" leaks........."
He write on a few forums as SlantSixDan, on ForABodiesOnly & SlantSix Forums in is very well respected.
Here is his Engine Flush Elixir.
https://www.slantsix.org/forum/viewtopic.php?t=11432&start=15
SlantSixDan Daniel Stern Engine Flush Procedure:
--------------------------------------------------------------------------------
"Careful-careful-careful. Those "engine flush" compounds you can find at the auto parts store can do a tremendous amount of damage.
I have long maintained that your engine is not a toilet (Chevrolet Vega, Cadillac HT4100 and V8-6-4, and Ford 3.0 owners excepted) and therefore does not need flushing except under specific and rare conditions as a corrective measure. Everyone's got a pet theory on how best to flush a crudded-up engine without pulling the pan. Some methods are harmless but ineffective. Some methods are potentially harmful. Some methods are harmless and effective. For best results, pick one of that last kind.
I do not believe there is any such thing as a safe, effective and fast engine flush procedure. You can pick any two of these three: Safe and effective (but not fast), safe and fast (but not effective), effective and fast (but not safe). The risks fall into two categories:
- Softening/damaging engine gaskets and seals so they don't seal well any more
- Sweeping large amounts of dirt and crud from its resting place into the oil filter, which plugs and goes into bypass mode, sending the crаp directly to the bearings and quickly failing the engine. I watched this happen to a Chev 305 once. It was quite a spectacle.
which is a specialized solvent that's very good at one particular task: Cleaning the mayonnaise out of a crankcase that's had coolant in it due to a faulty head (etc.) gasket. Their use in any other situation is risky.
My own engine flush recipe is a delicious blend of Marvel Mystery Oil (very light weight and good at dissolving gums and sludges), Kroil (best penetrant on the planet), ATF (detergent/dispersant with good lubricity), and Berryman B12 ChemTool (good at dissolving crud too tough for Marvel Mystery Oil).
My procedure involves warming up the engine, draining the oil, changing the oil filter, replacing the drain plug (!), and pouring in the soup. For a 5-quart crankcase, I usually start with 1/1/2/1 (Marvel/Kroil/ATF/B12). Then start and run the engine in the driveway at around 1200 to 1700 RPM with no sudden acceleration and no load applied, for 15 minutes.
Shut down, drain (really let it drain, walk away for 45 minutes), change the filter again, repeat with new soup for 30 to 45 minutes depending how gross the first batch of soup was when it was drained and how quickly the second batch of soup cruds up. Check the dipstick periodically.
If the 2nd batch of soup comes out coalmine black and full of chunks, run in another batch of soup (and another new filter!) and repeat until chips, chunks and tar stop coming out when you drain it. Then it will also be a good idea to service the oil pressure relief valve to make sure it's doing its job, as described in these two threads: thread 1, thread 2.
You'll note the filter is replaced before any attempt is made to introduce a flushing agent into the crankcase, and the filter is replaced again every time you drain a batch of flushing soup. Without doing this, you run the very real risk of inundating the filter, which will go into bypass mode and send all the loosened-up crud directly to the bearings and other critical parts: Goodbye, engine, it was nice gnawing you.
I've gotten amazing amounts of corruption and trash out of engines using this recipe and method. Other methods and other recipes may work better
for other people with other cars. The Kroil people (Kano Labs) have an engine cleanout "soup" of their own they call Kreen; I've had great results with pretty much every one of their products I ever tried, but I don't have enough direct experience with Kreen to comment. And as always, be advised that if the engine is really tired and whipped, even a safe flush can cause additional problems in the form of "new" leaks........."
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Apparently ATF has no more dispersants than motor oil. That being the case maybe he should replace the ATF in his brew with fresh motor oil
Thats quite the concoction….honestly I don’t trust it over any other flush.
Agreed. I'd rather trust a well known flush from a reputable company like BG's EPR-109 or Liqui-Moly Engine Pro-Line engine flush than some concoction someone made because their father-in-law's cousin's uncle's best friend told him that it works better because he used it in his 1932 farm tractor.
Diesel and ATF may have worked great.....back when JFK was president. I think engine and motor oil technology is a bit different now vs then.
And with how expensive Kreen and Kroil is....no way I'm wasting that putting it in my engine!
I believe pre 1972 ATF contained sperm whale oil and was capable of cleaning. The reputation has carried on without the “special” ingredient.
@cadchris - So his recipe, posted over 20 years ago, for motors that might have been 20 years old at that point is what you would recommend for a current flush? That was also his posts for motors that almost 99% were run on dino conventional for unknown periods. I'll take the advice of oil engineers and chemists working with stuff from this decade. He references getting chunks out using that and repeat until you don't. If your motor is getting chunks by any method you have a lot more issues. The viscosity of that "soup" as he calls it might be less than 0W-8.
I use to do Gunk Motor Flush way back, maybe 1x per year as that is what dad taught me. We always did good OCI intervals using name brand oils, mostly conventional back then. Pretty much the same now IMO as doing BG EPR, Liqui Moly and a couple others as long as done basically at idle or by instruction right before an oil change.
MMO has it's followings (as does Lucas) and some here had good experiences with it to help by thinning out the oil some for issues caused by other oil concerns. There are VOA's here, reviews/analysis by very knowledgeable respected members that any solvents in it flash off at a pretty low temperature leaving just whatever thin oil in the system.
Off topic- He also does not believe in LED's or HID's but that is more for plug and play as reflectors are not designed for it (not totally wrong). There were discussions on full projector retrofits and IIRC he does not approve of those due to glare concerns. YMMV
I use to do Gunk Motor Flush way back, maybe 1x per year as that is what dad taught me. We always did good OCI intervals using name brand oils, mostly conventional back then. Pretty much the same now IMO as doing BG EPR, Liqui Moly and a couple others as long as done basically at idle or by instruction right before an oil change.
MMO has it's followings (as does Lucas) and some here had good experiences with it to help by thinning out the oil some for issues caused by other oil concerns. There are VOA's here, reviews/analysis by very knowledgeable respected members that any solvents in it flash off at a pretty low temperature leaving just whatever thin oil in the system.
Off topic- He also does not believe in LED's or HID's but that is more for plug and play as reflectors are not designed for it (not totally wrong). There were discussions on full projector retrofits and IIRC he does not approve of those due to glare concerns. YMMV
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