Motor oil can only clean the first layer of contamination" - Terry Dyson, Dyson Analysis
"Flush" is perhaps an overused and misunderstood term. I prefer the term: "cleaning", or more precisely "internal engine oil system cleaning". A clean engine allows the oil to do the intended job.
Solvent Flushes - Some engine flush products and systems can be harmful to your engine and really don't clean as well as advertised. I will not comment on the various machines and proprietary solvents used at lube centers and some auto repair shops other than the idea of aromatic solvent under pressure flowing through an engine does not appeal to me. Solvent under pressure could potentially dislodge large chunks of deposits, clogging passages with little chance of further dissolving. There is also concern with this pressure on seals. The solvent products used only under idle conditions are generally safer than the pressure flushes, but under NO circumstances would I recommend driving with these solvent products or diesel fuel, ATF, or other "cleaning product" in the crankcase that severely dilutes, thins and shears motor oil. Lastly there is always the question of how much solvent remains. This is certainly a concern. Always allow a long drain period to allow the diluted oil to run out (which it should readily do) but also allow the aromatics to evaporate from the warm opened engine. Following a treatment with a good solvent cleaning, I recommend a short oil change interval. AMSOIL engine flush is an idle only product that is not harmful but does fall short in the actual cleaning performance. AMSOIL engine flush is simply poured into the crankcase (after installing a NEW oil filter), the engine is idled 15 minutes, shut down, then drained for as long as possible with filter removed.
Tear down and clean - This would be good if you could, but it usually requires a few weekends, some big cash, some thick books, many years of knowledge and maybe a little intestinal fortitude. Usually advised only if you have a mechanical problem, a problem that requires tear down anyway. Not practical for your otherwise fine running Volvo turbo, Lexus or Suburban.
Synthetic oil cleaning- Synthetic oil alone will clean some areas of your engine, some areas where oil pools and even some oil galleys will be cleaned a bit with synthetic oil alone. Some issues with this, the cleaning will be slow at best, and even though it may not sound logical - this cleaned contamination will be put into suspension in your oil and reduce the time you can use the oil via contamination. Another issue, is that some areas just will not be cleaned with the oil alone. A good example are the ring grooves and the surfaces of the rings.
Additive cleaning- This is a new area of engine cleaning. Most of the chemistry is relatively new, but don't let that scare you, because A) it is very safe B) the ester based compounds are natural. I highly recommend a product called Auto-Rx® . The usage instructions, which are updated periodically on the Auto-Rx® web page, are subdivided somewhat logically into low/high mileage treatment categories. This makes sense because cars with more miles will have a tendency to have dirtier engines, but car and engine type, driving style, maintenance routines, oil variety also play large roles in how much dirt and sludge will be built up. A car with under 50,000 miles of stop and go driving with petroleum oil changed at 8,000 mile intervals (if the owner remembers) could have a sludge problem that needs cleaning.
So why clean your engine?
If you are switching over to synthetic oil, some of the benefits will become much more apparent if you start with a clean engine. Longer oil change intervals, better cooling, more power are just a couple key characteristics that are enhanced if old petroleum oil residues are removed. Just changing to any synthetic oil will not completely clean your engine - honestly I used to think this - but there are just some locations in the engine that oil won't clean. Auto-Rx® will clean these areas and allow the synthetic oil to keep the rings free floating, thus allowing a better compression seal and result in more power and less emissions, for example.
If you start with a seriously clean engine your oil will last longer and frankly will protect the engine better. Many of the deposits and crud, and especially the more harmful by-products of petroleum oil oxidation tend to have an acidic reaction. This will deplete the additives in any motor oil.
OUTLINE OF MY BASIC THOROUGH HIGH MILEAGE INTERNAL ENGINE CLEANING PROCESS
This process applies to the worst case scenario car. The project car. It's not necessarily risky but only the first portions apply to a well maintained vehicle simply changing over to synthetic oil. If you are simply changing over a relatively well maintained car to Amsoil the regular or high mileage Auto-Rx® treatment will be great.
Those of you familiar with my earlier 2000-2002 version that covered fuel injector cleaning during the engine cleaning process, I have left this out for sake of clarity. Again this process takes a bit of patience, attention to detail and some driving miles. If you have any questions don't hesitate to ask.
1) Acquire 3 bottles of Auto-Rx® (ideally do the 3 for the price of 2 deal), 1 can of Amsoil engine flush, enough good quality inexpensive petroleum motor oil (Chevron products seem to work well for this) for 4 changes, 5 filters and your Amsoil motor oil.
2) Run the high mileage application instructions per the Auto-Rx® instructions. (7/20/03 sample instructions below) This will use two of the bottles of the Auto-Rx® and in most circumstances will be all you need to the clean engine very well. If you know the engine to be very dirty or the engine did not have good oil/oil service history do not change to synthetic yet, just fill with the dino oil at the end of the second Auto-Rx® application.
Do those high priced oil additives help or hurt your engine?
Oil additives, you know the ones that almost everyone has tried and most have not seen much difference, Yea those. Lets talk about what is really in them and what they can do to your engine.
There are hundreds of oil additives on the market. Some say that they will reduce your mileage, or reduce your wear, or reduce your oil consumption, and some even say that you can run your engine without any oil after treating your engine with their miracle cure additive.
The truth is that there are 4 types of oil additives.
1. Solvent is one and it only cleans out deposits left by using a poor oil. If you use a good oil you should not need to use a solvent in your engine. Think about it, there is many places in your engine that dont drain all the oil out of. You know the small little valleys that hold the oil and doesnt drain oil. That still has the solvent it them and will contaminate your new fresh oil. Solvent will clean out your engine but at what cost? Solvent is made to break down oils and I for one would never use a solvent in my engine because it would start to break down my new fresh oil and reduce the oils ability to properly lubricate my engine.
2. PTFE is another one. This additive has plugged up filters has an ability to build up on itself and affect tolerances in your engine. It only has a 500 deg F. temperature range and only holds up to 5,000 psi. Moly has a 650 deg F. temperature range and holds up to 400,000 psi. Some oils have moly in them and if you were to put the PTFE in your engine with the moly, you would be diluting the quality of an average oil.
3. Chlorinated paraffins is the most popular additive. They show how their oil will perform in a pressure test that has a torque wrench that puts pressure on a bearing and a round but rough surface that is turning in the test oil. They show how by adding their oil the wear is greatly reduced. This can be done with household bleach but you would not want to put any of that in your engine because its corrosive. The Chlorinated paraffins are also corrosive to the light metals in your engine. The lead in your engine bearings is subject to corrosion or acids that can build up. When the chlorinated paraffins come in contact with moisture or water of any kind they turn into hydrochloric acid and can become acidic to the lead in your bearings. So the reduction in wear shown by the torque wrench test is only one realm of wear that goes on inside your engine. Acidic or corrosion wear is another type and that is why I would never use an additive containing any type of chlorinated product.
4. The last type of additive is just a SAE 20 or 30 wt that has the same additives your engine oil comes with in the first place. In some cases there seems to be no thought to what might happen if there are to many additives and the oils additive balance is thrown off by throwing a bunch of everything in your oil. This is the additive type that is least harmful but I would recommend against using it also.
Stick with the better oils on the market like Mobil-1 or Lubrication Engineers. Lubrication Engineers is not as popular as the Mobil-1 oil and but has a lower wear rate and like the Mobil-1 does not need any additive to make it good. LE oils can be purchased at Mag-Hytec at 1-818-786-8325 and Mobil-1 is everywhere.
If you use the best you wont need those additives. I use the LE oil myself and recommend against using any other additives in any oil.
Confused? Check out the Glossary of Terms
ToyotaOffRoad.com Note: Kevin Dinwiddie is a Certified Lubrication Specialist by the STLE (Society of Tribologists and Lubrication Engineers) Shown on the STLE directory under Lubrication Engineers. Kevin has worked for Lubrication Engineers for over 22 years. He holds a degree is in mechanical engineering and has been involved in the testing of oils for over 12 years and working with industrial customers for 22 years.
Mag-hytec sells the LE oils in quart quantities 4 or 5 quarts at a time. They generally deal with industrial customers. A small order for them would be a 55 gallon drum. The cost per quart is $5.00US.
ToyotaOffRoad.com is not in anyway affiliated with Lubrication Engineers, Mobile-1, Mag-hytec or any of their subsidiaries.
