Liqui-Moly Engine Flush

To some of the comments above:

I collected a sample before I added the flush. Then I added the flush (to warm oil), ran 10 min per LM's instructions, drained and collected a second sample which was lower viscosity than the first obviously due to the water-like viscosity of the flush. Just making sure you understand/think there was some confusion. Pre and post-flush samples below.
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How does this prove it did anything at all? I have tried this product and found it did little to nothing on engines that really needed to be cleaned because of sticking lifters and rings due to poor maintenance.
I much prefer the cleaning action of Mobil 1 0w40 to these products, the proof it really cleans not just keeps the engine clean is undeniable.

Show some pictures of the bottom of pistons being cleaned with this product, let see how good it is. This is Mobil 1 0w40 after about a year, the piston at the top is covered by the pickup tube but still getting cleaned the one on the bottom and the others are almost free of varnish and deposits, the oil droplets are showing a red tint, that is the varnish, the top end was totally cleaned. The top piston is an indicator of the varnish and junk on the others and this area just gets splash oil.


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How does this prove it did anything at all? I have tried this product and found it did little to nothing on engines that really needed to be cleaned because of sticking lifters and rings due to poor maintenance.
I much prefer the cleaning action of Mobil 1 0w40 to these products, the proof it really cleans not just keeps the engine clean is undeniable.

Show some pictures of the bottom of pistons being cleaned with this product, let see how good it is. This is Mobil 1 0w40 after about a year, the piston at the top is covered by the pickup tube but still getting cleaned the one on the bottom and the others are almost free of varnish and deposits, the oil droplets are showing a red tint, that is the varnish, the top end was totally cleaned. The top piston is an indicator of the varnish and junk on the others and this area just gets splash oil.
It doesn't prove anything nor did I make any claims. Just providing data so you can make you own opinion.
 
Wouldn't flushing remove the oil film that protects during startup? Dont get me wrong as I have used a Gumout Flush at 4 ounces for 5 minutes very occasionally but wouldnt continued use just create more engine wear? Removing any left over oil that is in place to keep metals protected? Someone here posted within the last 6 months or so that they do these flushes with a high tech machine that hooks up into the motor and unless its being done by that procedure its only "wetting" and not really doing enough. Finally,seems like the need to flush a lot tells a story of a oil not up to par or being ran to long. I'm sure the LM flush is decent stuff,as is other brands but isnt flushing kinda emergency situation only or part of regimental maintenance? I'll sit back and try to read and learn as I am curious to whats viable,nonsense or OCD.
 
How does this prove it did anything at all? I have tried this product and found it did little to nothing on engines that really needed to be cleaned because of sticking lifters and rings due to poor maintenance.
I much prefer the cleaning action of Mobil 1 0w40 to these products, the proof it really cleans not just keeps the engine clean is undeniable.

Show some pictures of the bottom of pistons being cleaned with this product, let see how good it is. This is Mobil 1 0w40 after about a year, the piston at the top is covered by the pickup tube but still getting cleaned the one on the bottom and the others are almost free of varnish and deposits, the oil droplets are showing a red tint, that is the varnish, the top end was totally cleaned. The top piston is an indicator of the varnish and junk on the others and this area just gets splash oil.


View attachment 32935
I cant run 0w40 M1 as its probably a bit too thick for the winter but the bottom looks good in this application. Though the RL is pretty thick but luckily its getting the 0w20 5w20 RL for the months to come.
 
I cant run 0w40 M1 as its probably a bit too thick for the winter but the bottom looks good in this application. Though the RL is pretty thick but luckily its getting the 0w20 5w20 RL for the months to come.
What? An oil is never too thick unless it gels near the pickup tube and cannot be pumped. But that will not happen with a 0W rated oil unless it's around -50F or below. Is that your worry? If it is then it's the same worry with the other oils as well.
 
If you're going to use an engine flush, the Liqui-Moly product to use is their Pro-Line Engine Flush which comes in 500 ml cans (good for up to 5 liters). This is their most concentrated formula. Although the recommended duration is 10 minutes, you can run it up to 20 minutes at idle with no ill effects provided you do NOT raise idle speed.

I've been using it for 9 years with no ill effects, but do not expect a day and night difference simply running it for 20 minutes straight the first time. If the engine is sludged, Liqui-Moly have recommended their Öl-Schlamm-Spülung for 300 km (188 miles) prior to an oil change. If you use the translate feature on your browser, this is an interesting and short blog post from Liqui-Moly.

From experience, I would highly suggest replacing the oil filter at the very least, as it does get pretty nasty and turns the oil dark red. Maybe even change the oil with cheap mineral oil, put a decent filter on and run this stuff before changing the oil.
 
If you're going to use an engine flush, the Liqui-Moly product to use is their Pro-Line Engine Flush which comes in 500 ml cans (good for up to 5 liters). This is their most concentrated formula. Although the recommended duration is 10 minutes, you can run it up to 20 minutes at idle with no ill effects provided you do NOT raise idle speed.

I've been using it for 9 years with no ill effects, but do not expect a day and night difference simply running it for 20 minutes straight the first time. If the engine is sludged, Liqui-Moly have recommended their Öl-Schlamm-Spülung for 300 km (188 miles) prior to an oil change. If you use the translate feature on your browser, this is an interesting and short blog post from Liqui-Moly.

From experience, I would highly suggest replacing the oil filter at the very least, as it does get pretty nasty and turns the oil dark red. Maybe even change the oil with cheap mineral oil, put a decent filter on and run this stuff before changing the oil.
The way I look at it is the LM Proline Engine Flush is simply additional cleaning every change on top of what the oil's detergent pack is doing whether I need it or not . Seems to be a worthwhile maintenance items for $10 a few times a year to ensure that things inside stay sorted.
 
The way I look at it is the LM Proline Engine Flush is simply additional cleaning every change on top of what the oil's detergent pack is doing whether I need it or not . Seems to be a worthwhile maintenance items for $10 a few times a year to ensure that things inside stay sorted.

Using it as a preventive maintenance item will yield results in the long run. While a lot of oils have excellent cleaning properties, such as Mobil 1 0W-40 mentioned by Trav, and do a great job keeping engines clean over long drain intervals, I use Pro-Line Engine Flush as more of a "rinse" prior to an oil change, particularly with extended drains.

The primary elements in Pro-Line Engine Flush are petroleum ether, calcium salt, calcium-based alkylaryl sulfonate detergent, benzenesulfonic acid, PEA and non-ionic surfactant. They also have a "proprietary" agent in there, but there's no detail on what exactly it comprises of. It does a pretty good job, and works well unsticking piston rings from my experience.

In one particular application, a Mitsubishi 3.5L DOHC V6 (6G74 series), there was an issue with oil coming out of the PCV valve and the dipstick not fully seating after the engine's been running. The oil also reeked of gas and would turn dark very quickly. I ran Pro-Line Engine Flush for 25 minutes and repeated the process three times after 500 km (313 miles) intervals using Pennzoil LongLife Gold 15W-40. After the third interval, the oil retained more of a golden color for 2,500 km (1,563 miles) before it started to darken, and the amount of oil coming out of the PCV valve was significantly reduced. The dipstick was seating properly, and once the PCV valve was replaced, oil consumption was no longer a big issue. Proper to replacement, it would consume about a liter every 1,500 km (938 miles) and went to no make up oil between 5,000 km (3,000 mile) drains. The engine's still running great to this day, and the owner continues to use Pro-Line Engine Flush every second oil change.

Long story short, some products do have a place, and this is definitely one of them. Of course, there are various other products and methods you can use.
 
Using it as a preventive maintenance item will yield results in the long run. While a lot of oils have excellent cleaning properties, such as Mobil 1 0W-40 mentioned by Trav, and do a great job keeping engines clean over long drain intervals, I use Pro-Line Engine Flush as more of a "rinse" prior to an oil change, particularly with extended drains.

The primary elements in Pro-Line Engine Flush are petroleum ether, calcium salt, calcium-based alkylaryl sulfonate detergent, benzenesulfonic acid, PEA and non-ionic surfactant. They also have a "proprietary" agent in there, but there's no detail on what exactly it comprises of. It does a pretty good job, and works well unsticking piston rings from my experience.

In one particular application, a Mitsubishi 3.5L DOHC V6 (6G74 series), there was an issue with oil coming out of the PCV valve and the dipstick not fully seating after the engine's been running. The oil also reeked of gas and would turn dark very quickly. I ran Pro-Line Engine Flush for 25 minutes and repeated the process three times after 500 km (313 miles) intervals using Pennzoil LongLife Gold 15W-40. After the third interval, the oil retained more of a golden color for 2,500 km (1,563 miles) before it started to darken, and the amount of oil coming out of the PCV valve was significantly reduced. The dipstick was seating properly, and once the PCV valve was replaced, oil consumption was no longer a big issue. Proper to replacement, it would consume about a liter every 1,500 km (938 miles) and went to no make up oil between 5,000 km (3,000 mile) drains. The engine's still running great to this day, and the owner continues to use Pro-Line Engine Flush every second oil change.

Long story short, some products do have a place, and this is definitely one of them. Of course, there are various other products and methods you can use.
Probably the most intelligent comments I've read about flushes here.
 
Highly doubt it - idling is almost zero load which is why they recommend you idle vs. drive it. Figure if they tell you 10-15min the engineering safety factor here is probably hours to deal with your average person that doesn't read the direction....ahhahahaa

Maybe. That's a fairly reputable company so perhaps they provide a generous safety-factor/effectiveness equation for consumers own good.

I can tell you first hand a can of Gunk 5-minute motor flush isn't so friendly to dumb mistakes. Many years ago I was went on a college road trip in my Jeep Cherokee 4.0. As we were heading past my hometown i stopped by my folks place to do an oil change. My Dad was an engineer and taught me long before I could drive that proper maint was a key part of car ownership.

I wasn't just gonna change the oil and filter. I was gonna do the "worlds greatest oil change".

It started off with an engine flush. I poured in the can being careful not to overfill. I started it up and let it idle. My Dad wanted to go over my route so we sat at the kitchen table and discussed pro's and con's of various roadways. 20-30 minutes later I remembered the Jeep was still running!! I played it cool and said I was just gonna check on things out in the garage. I panicked when i realized I had exceeded the recommended time by 5x.

The drain was spooky. Pitch black and a little chunky. Could have been the suction causing weird flow pattern out the plug hole but it looked chunky. There were no metal shavings. I snugged the plug/bolt back up and moved on to change the filter.

Oil filter on a 4.0 is as easy as it gets. Nothing wrong with the old Fram filter on quick inspection. Put a Mopar filter on it.

Filled with 5-6 quarts of Mobil 1 10-30. Checked for leaks at idle. Verified correct oil level. Hit the road.

We didn't make it 100 miles before the truck started feeling sluggish, running hot and eating fuel. It didn't have cruise and I didn't notice the increased pedal effort. As the sun set behind us on the highway I noticed how badly my back window needed to be cleaned. When stopped for fuel I noticed a lot of oil dripping out of the air filter housing just behind the driver headlight. It was all over my wheel wells, thankfully not on my brakes but all over the tailgate and window. I had to throw out the air filter. I checked the oil level and it barely registered on the stick. I popped the oil fill on the valve cover with it idling and saw a huge amount of blowby. The engine sounded fine and ran smooth but we had obvious issues with either the pcv system or, more likely, the flush trashed one or more of my cylinders.

The solution presented itself at the auto parts store across the street from the gas station. I bought 6 bottles of motor honey and 6 quarts of 20w-50. Every hundred miles or so I'd stop for fuel and check the oil levels. It still fell quickly but predictably. I rationalized a ratio of 1/2 bottle honey to 1 quart oil every 100-200 miles. The engine continued to run perfectly and we made good time with no additional drama from the Jeep.

I drove it like that for about 2 weeks and 2000 miles. It left a small puddle anywhere it was parked but keeping the revs down and using the super thick oil mixture really slowed down the blowby. When I finally got around to pulling the cylinder head I was surprised to see a gouge in the #1 cylinder almost big enough to stick a toothpick! Must have been caused by a chunk of carbon that broke loose but didn't clear out. I replaced that engine myself with a "low mile" junkyard engine for $800.

Bottom line: if you flush, remember its basically kerosene with some posh extras and follow the directions to the letter. I'll use Liquimoly or BG flush from time to time on a new-to-me vehicle but I use a darn stop watch now and wont take my eyes off it even if the garage is on fire.
 
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Maybe. That's a fairly reputable company so perhaps they provide a generous safety-factor/effectiveness equation for consumers own good.

I can tell you first hand a can of Gunk 5-minute motor flush isn't so friendly to dumb mistakes. Many years ago I was went on a college road trip in my Jeep Cherokee 4.0. As we were heading past my hometown i stopped by my folks place to do an oil change. My Dad was an engineer and taught me long before I could drive that proper maint was a key part of car ownership.

I wasn't just gonna change the oil and filter. I was gonna do the "worlds greatest oil change".

It started off with an engine flush. I poured in the can being careful not to overfill. I started it up and let it idle. My Dad wanted to go over my route so we sat at the kitchen table and discussed pro's and con's of various roadways. 20-30 minutes later I remembered the Jeep was still running!! I played it cool and said I was just gonna check on things out in the garage. I panicked when i realized I had exceeded the recommended time by 5x.

The drain was spooky. Pitch black and a little chunky. Could have been the suction causing weird flow pattern out the plug hole but it looked chunky. There were no metal shavings. I snugged the plug/bolt back up and moved on to change the filter.

Oil filter on a 4.0 is as easy as it gets. Nothing wrong with the old Fram filter on quick inspection. Put a Mopar filter on it.

Filled with 5-6 quarts of Mobil 1 10-30. Checked for leaks at idle. Verified correct oil level. Hit the road.

We didn't make it 100 miles before the truck started feeling sluggish, running hot and eating fuel. It didn't have cruise and I didn't notice the increased pedal effort. As the sun set behind us on the highway I noticed how badly my back window needed to be cleaned. When stopped for fuel I noticed a lot of oil dripping out of the air filter housing just behind the driver headlight. It was all over my wheel wells, thankfully not on my brakes but all over the tailgate and window. I had to throw out the air filter. I checked the oil level and it barely registered on the stick. I popped the oil fill on the valve cover with it idling and saw a huge amount of blowby. The engine sounded fine and ran smooth but we had obvious issues with either the pcv system or, more likely, the flush trashed one or more of my cylinders.

The solution presented itself at the auto parts store across the street from the gas station. I bought 6 bottles of motor honey and 6 quarts of 20w-50. Every hundred miles or so I'd stop for fuel and check the oil levels. It still fell quickly but predictably. I rationalized a ratio of 1/2 bottle honey to 1 quart oil every 100-200 miles. The engine continued to run perfectly and we made good time with no additional drama from the Jeep.

I drove it like that for about 2 weeks and 2000 miles. It left a small puddle anywhere it was parked but keeping the revs down and using the super thick oil mixture really slowed down the blowby. When I finally got around to pulling the cylinder head I was surprised to see a gouge in the #1 cylinder almost big enough to stick a toothpick! Must have been caused by a chunk of carbon that broke loose but didn't clear out. I replaced that engine myself with a "low mile" junkyard engine for $800.

Bottom line: if you flush, remember its basically kerosene with some posh extras and follow the directions to the letter. I'll use Liquimoly or BG flush from time to time on a new-to-me vehicle but I use a darn stop watch now and wont take my eyes off it even if the garage is on fire.
I suppose if you look at the UOA I posted of the old oil with LM Engine Flush, it looks like a 30w with some fuel dilution - how can that possible do any damage? Folks drive around with thinner oils with more dilution all the time.
 
I suppose if you look at the UOA I posted of the old oil with LM Engine Flush, it looks like a 30w with some fuel dilution - how can that possible do any damage? Folks drive around with thinner oils with more dilution all the time.
I'm sure its a good product. Used it myself. Prob could run it for days although Im a little gun shy about not following engine flush directions. Just saying the safety factor of that product must be higher than a can of Kerosene that, in my personal experience, has a small safety factor.
 
It doesn't prove anything nor did I make any claims. Just providing data so you can make you own opinion.
To all of your questions the answer is yes. I don't know why you asked a rhetorical question when it does clean the engine and flushes out gunk, sludge, shavings, and if you leave it long enough, will damage the seals and gasket.
 
I just used the Liqui-Moly Engine Flush, ran it for 30min instead of 10min it says on the label. Wow this stuff works great. Just be sure the engine is up to temp before using.
Haven't heard alot about the liquid moly so good to hear. Have heard lots about the seafoam (the guys who believe in it REALLY believe in it)
 
Haven't heard alot about the liquid moly so good to hear. Have heard lots about the seafoam (the guys who believe in it REALLY believe in it)
Seafoam is good stuff. When I was in school it was right next to a nursing home we stuck the Seafoam in a 1973 Ford Gran Torino and man that thing smoked and cleaned out like crazy the nursing home called the fire department because they thought the school was on fire LOL.
 
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