What You Should Know about Recycled Engine Coolant / Antifreeze

By Roy Berndt
Program Manager

PROFormance Powertrain Products There is not a one of us that has not been effected or knows someone that has been effected by the economic crisis, downturn, recession or whatever catch phrase that is being used this week in an effort to try and keep us from focusing on one reality that we all are aware of; "the cupboards are bare" in the words of old Mother Hubbard. This TechTip topic for many of us as individuals may not be a big deal but is certainly getting a lot of attention in the world of fleets, and even the OE's "recycled engine coolant/anti-freeze". We as individuals have a major impact as well but it is on the disposal side.

Recycled engine coolant/anti-freeze is a relatively new and emergent industry that got its start in the late 80's. Why? The result of passed federal government regulations that materials containing lead levels of more than 5.0 ppm as hazardous; a category that most used engine coolant fell into. You now had equipment and vehicle maintenance facilities looking for methods by which to comply and reduce the cost of their new hazardous waste disposal cost, and preserve the environment. This demand to reduce hazardous wastes and related costs created opportunities for many different companies and groups to develop and market effective means to recycle used engine coolants. Since ethylene and propylene glycol are economically recoverable components in engine coolants, many different ways were developed to separate out the contaminants from the ethylene or propylene glycol. The various processes included simple filtration, ultra-filtration, chemical precipitation and filtration, reverse osmosis, ion-exchange, and distillation.

As this young market developed and entrepreneurial opportunities presented themselves several technologies developed, clearly many were producing inexpensive and poor quality recycled engine coolants while others provided higher quality recycled engine coolants. This led to significant, and understandable, concern from OEMs and state regulatory bodies. Without industry standards, there was inevitably going to be a clash between engine manufacturers and recycled coolant providers with warranties and responsibility.

  • • Antifreeze/engine coolant is the most neglected fluid in the vehicle.
  • • Cooling system neglect is cited as the principal reason for premature engine and transmission failure.
  • • Cooling system failure is the most common cause of mechanical breakdown on the road.
  • • A national survey found that 7 out of 10 vehicles contain rust and scale and two thirds of more than 8,000 cooling system repair jobs were performed on an emergency basis.
  • • Just 1/16th of an inch of mineral deposits on 1 inch of cast iron reduces heat dissipation by 40%.

While ASTM (American Society for Testing and Materials) was in the process of developing industry standards, OEMs such as General Motors, Ford, Chrysler, Caterpillar, and Cummins developed proprietary standards in response to the demand of the field. After developing these standards, they issued company- or process-specific approvals. Testing and approval programs varied in intensity, however; they were primarily based around virgin engine coolant requirements. Interestingly enough, standards for pre-mixed coolant where in the mix as well. With many bi-metal, or all aluminum engines, inundated with electronics throughout, the worst potential enemy to your engine coolant could very well be the water that you use for your 50/50 mixture. Listed below are a few of the issues with the water out of your garden hose.

  • • Calcium and Magnesium – Calcium and magnesium salts form scale on hot heat exchange surfaces. Scale impedes heat transfer and causes localized hot spots that result in engine overheating and component failure.
  • • Chloride and Chlorine – All municipal water supplies contain chloride and chlorine. Chloride is very corrosive to all cooling system metals, especially aluminum. Chlorine forms additional chlorides in the cooling system.
  • • Sulfate – All municipal water also contains sulfate that contributes to general corrosion and scale formation.
  • • Oxygen – Deionized water doesn't taste good due to the lack of oxygen and certain minerals. Tap water, however, is full of oxygen and other minerals making it suitable for drinking and aquariums. Oxygen contributes to metal corrosion and depletion of inhibitors. Water with low oxygen is preferred for engine coolant.

If that isn't bad enough even if correct water is being used you have mixing mistakes - Cooling system problems can also be caused by improper dilution of the coolant/antifreeze with water.

These problems include:

  • Improper ratio of concentrate to water
  • Not stirring thoroughly to mix the water and concentrate
  • Mixing the concentrate and water in a dirty container
  • Pouring the concentrate and water into the radiator without first mixing them

Resulting damage of poor coolant maintenance and/or poor water quality Radiator

So if you have used water from your garden hose to mix your coolant, you are overdue for cooling system maintenance deposits have been building up. Maybe you already have had the radiator rodded out, unfortunately, the engine block and heads have the same deposits. A quick acid flush (which can attack copper, aluminum, and brass) will NOT remove what took years and tens of thousands of miles to build up. So you can see how you could actually be better off to use pre-mixed antifreeze and keep the cooling system clean in the first place. The other issue with using water from your garden hose is that is has a detrimental effect on additive package in your coolant to keep the system clean and free from corrosion, insure long life of the seals and maximize the cooling capability.

The cooling system consists of a radiator, water pump, hoses, fan(s), heater, thermostat and engine coolant. The cooling system removes excess heat from the engine block and heads, keeps the engine operating at its most efficient temperature, and gets the engine up to the correct temperature as soon as possible after starting. Ideally, the cooling system keeps the engine running at its most efficient temperature no matter what the operating conditions are.

Environmental issues require cleaner burning engines. Engine manufacturers have raised engine operating temperatures in order to reduce exhaust emissions and improve fuel economy. Today's engines run on the borderline of overheating, with in-cylinder combustion temperatures around 2,000 °F.

As fuel is burned in the engine, about one-third of the energy in the fuel is converted to kinetic energy for moving the vehicle. Another third goes out the exhaust pipe and the remaining third is removed by the cooling system. If no cooling were provided, metal parts would melt and the pistons would seize. The engine coolant must have indirect contact with the combustion chamber, the cylinder walls, and the valve seats and guides. As the engine coolant circulates through the engine, it picks up heat from the engine. The coolant releases this heat as it passes through the radiator.

Worldwide, over 400 million gallons of antifreeze concentrate are sold each year. After the typical 50% dilution with water, this yields about 800 million gallons of engine coolant. Between 25 and 50% of this volume ends up improperly in the environment, and dumping by consumers is a major cause of this pollution. Approximately 90% is mixed with wastewater, treated, then discarded to surface waters. Improperly disposed antifreeze can have devastating effects. Antifreeze has a sweet taste that small children and animals can find attractive. If ingested, antifreeze affects the central nervous system and can cause death. A couple of states in the US require the addition of a bittering agent to make antifreeze less tasty to children and animals. Every year about 10,000 cats and dogs are victims of accidental poisoning by ingestion of antifreeze. Governments are imposing more regulations concerning antifreeze management. This means more antifreeze will be collected for beneficial reuse/recycling. Proper cooling system maintenance and good recycling practices can mitigate the harmful effects of antifreeze on our environment.

Antifreezes differ in more than color. Antifreeze is made using ethylene glycol or propylene glycol. Antifreeze producers use a number of different corrosion inhibitor packages (with descriptions such as heavy duty conventional with SCA, low silicate conventional without SCA (Supplemental Coolant Additives), OAT (Organic Acid Inhibitors), and hybrid OAT). Antifreezes can be the same color but use different inhibitor packages. Each unique antifreeze chemistry formulation performs differently. The vast majority of recycled antifreeze in the USA does not meet these standards. If you want to verify that the recycled coolant that you are purchasing is correct verify that you have D 6471, Specification for Recycled Prediluted Aqueous Glycol Base Engine Coolant Light-Duty Service; and D 6472, Specification for Recycled Glycol Base Engine Coolant Concentrate for Automobiles and Light-Duty Service. "Light duty" antifreeze is intended primarily for gasoline-engine passenger car applications. "Heavy duty" antifreeze is intended for diesel engines in both on- and off-highway applications. Diesel engines in heavy-duty truck and construction equipment have more severe corrosion prevention requirements than gasoline-engines in passenger cars and therefore require more corrosion inhibitors. Using "light duty" antifreeze in an over-the-road tractor will cause cooling system problems unless an SCA in proper amount is added to the antifreeze.

Heavy Duty is a bit more complicated and manufacturer specific however the following chart should help determine if you have a product that meets the engine requirements.

ASTM D-3306

John Deere 8650-5

EMD M.I. 1748E

ASTM D-4985


Ford New Holland 9-86

ASTM D-6210


Freightliner 48-22880

Case Corp. MS1710


GM 1825


SAE 1941

GM 1899

Cummins S/B 3666132


Volvo GM

Detroit Diesel 7SE298

TMC RP 329

Waukesha 4-1974D

US government specification CID-A-A-52624 covers requirements for ethylene glycol and propylene glycol antifreeze and allows three different concentrations: 100%, 60%, and 50%. CID-A-A-52624 requires the antifreeze "to be suitable for use in all administrative vehicles, construction and material handling vehicles and equipment, and military ground combat and tactical vehicles and equipment." The US government encourages the use of recycled antifreeze.

The last thought that I leave you with is this; if you have a recycled coolant that has not gone through the process of removing corrosive chloride salts, then you do not have a product that you are going to want to use. They are the hardest product to remove from recycled coolant but the one that can cause the most damage. Recycled coolant is a great way to be environmentally friendly and easy way for all of use individually and corporately to be "Green" with little or no effort, just make sure that you have a product that meets the standards and it is every bit as good as a virgin coolant and in some cases even better.

The Pitfalls of Surface Conditioning Disks

By Roy Berndt
Program Manager
PROFormance Powertrain Products

Nearly everything can have value; it just depends upon how it is used. For instance "rat poison" will certainly get rid of unsightly rodents and is usually fatal to humans. Except, of course, when it's used in the correct dosage. As a blood thinner for those with heart disease, it becomes a life-saving medication.

Well there is a "rat poison" for engines that is used regularly and daily in nearly any installation shop and by DIYers. SURFACE CONDITIONING DISCS, often referred to as cookies within the shop environment, were originally designed for use in the auto body shop, I believe.

Here is where the problem lies when using them to clean engine gasket surfaces, or for cleaning engine parts which are to be reused. If the intent is to have a surface that is perfectly clean and ready for the gasket to be applied, surface conditioning discs can do that quickly and give the APPEARANCE of a perfect surface. That is the up-side of these products – at least in the eye of the technician.

Surface conditioning discs are typically woven fiber pads that can be purchased in various degrees of abrasive grades somewhat similar to sand paper. They contain various different abrasives within their woven fibers, the most aggressive being Aluminum Oxide. As these discs are used on surfaces they break down and release large amounts of aluminum oxide along with the metal particles that are being removed from the base metal and results in a brushed look to it. (Fig 1)

Fig 1 Note the brushed-looking surface from using a surface conditioning disc. The action releases aluminum oxide as well as metal particles removed from the base metal.

The aluminum oxide along with the micro particles removed from the base metal are two of the most potentially damaging components that could be introduced into an engine. These particles ingested into an internal combustion engine, be it through the induction system or contamination of the lubricating oil system, will certainly cause a premature engine failure.

When introduced through the induction system, whether through the intake manifold or cylinder head ports, these particles will cause piston ring damage (Fig 2), premature cylinder and piston wear (Fig 3) as well as high oil consumption. The engine in these two illustrations had 100 miles of operation after being contaminated. This is how fast the damage can occur!

Fig 2 Piston rings with micro fibers and base metal from surface conditioning disc embedded onto their faces will prematurely wear the ring lands of the pistons as the rings rotate during the combustion cycle.

Fig 3 Piston skirt and cylinder wall damage caused by contaminants introduced through the induction system by surface conditioning discs.

When these same contaminants are introduced into the lubricating oil system the damage is horrific and immediate. Imagine adding lapping compound into your engine's oiling system: you can expect an abrupt failure in very short order. Aluminum oxide and base metal particles actually make a pretty good lapping compound, as illustrated by the crankshaft in Fig 4. Both the journal surfaces of the rod and main bearing journals already exhibit extreme wear as well as the thrust flange of the crankshaft. Other components that would be affected by these types of contaminants include camshaft bearing surfaces and cam lobes, lifters and lifter bores as well as timing chains and gears. In fact, any component that is contacted by the engines lubricating oil and rotates or moves will experience accelerated wear.

Fig 4 This crankshaft had 10 miles with oil contaminated with byproducts of surface conditioning discs. Note how much wear has already occurred on both the journal surfaces and the thrust flange on the right.

Is it impossible to use a surface refinishing disc and not cause engine damage? No. However the extent of cleaning that needs to be done is staggering. Cleaning with solutions, preferably high pressure vacuuming and flushing of all areas that have had any contact of any of the aluminum oxide dust, base metal or removed gasket materials is required, needs to be extensive, and is frankly not worth the chance of contamination. This all brings us back to using gasket scrapers, razor blades, plastic knives and gasket removing liquids/sprays to remove and clean gasket surfaces without the use of discs. The important issue here is a clean gasket surface and how it feels not how it looks. If it is clean and the surface feels clean and obstruction free, then there should be no issue with a gasket being able to seal.

The last item that we need to discuss about refinishing discs is the damage that you can do to the surface itself. A fresh surface refinishing disc can remove as much as .008. in just 15 seconds. That amount of material removed will invariably do more damage to the gasket's ability to seal than help it.

Bottom line, surface finishing discs are a wonderful tool in many walks of life and are truly a miracle tool in the body and fender repair world. However, when it comes to engines, whether a used engine, newly remanufactured engine or even an engine repair, they can be the kiss of death. Unless you have the means and resource to effectively clean all the contamination from surface refinishing discs you would be best to stay away from these tools. This contamination is easily identifiable by oil sampling of the engine and is a just cause to deny warranty.

In closing, don't think you'll be the exception and do a good job with them: there is not a single auto manufacturer that approves of surface refinishing discs. Whether domestic or foreign nameplate, no one approves the use of these tools for the engine. Many OE manufacturers even have caution bulletins to specifically not use this product on anything that has to do with the engine or parts that bolt to an engine. So if you are looking to the best job possible when it comes to engines, think twice about using surface finishing discs and avoid the potential damage and denied warranty by an engine remanufacturer be it after market or OE, if evidence is found of their use your warranty will be null and void.

Proper Filling of Engine Coolant

By Roy Berndt
Program Manager
PROFormance Powertrain Products

It seems that about every 15 years or so a new generation of technicians emerges on the scene that is passionate and excited about engines and vehicles. They may or may not have had some type of formalized education – yet they may be well versed and very savvy but have not had the infield experience as of yet. They are not necessarily young, just new to the world of engines. For them (and even for the veterans), let me give you some facts that you may not be aware of:

  • Antifreeze/engine coolant is the most neglected fluid in the vehicle.
  • Cooling system neglect is cited as the principal reason for premature engine and transmission failure.
  • Cooling system failure is the most common cause of mechanical breakdown on the road.
  • A national survey found that 7 out of 10 vehicles contain rust and scale and two thirds of more than 8,000 cooling system repair jobs were performed on an emergency basis.
  • Just 1/16th of an inch of mineral deposits on 1 inch of cast iron reduces heat dissipation by 40% and is the equivalent to 3-1/2 inches of cast iron.
  • Over 60% of water pump failure can be attributed to seal failure.
  • Over 50% of engine failures can be attributed to cooling system failure.

Well that gives you an idea of how critical the cooling system is to a long and happy engine life and how detrimental it can be if it is not in good operating condition. Worse yet, what if the cooling system was the cause of the vehicle engine failure and now has a fresh reman engine installed. What do you think is going to happen at that point?

The cooling system is just that a system (Fig 1) that is pressurized, sealed circulation that consists of 6 major components:

Anti-freeze/Coolant: The fluid in your cooling system is used as a way to dissipate the tremendous amount of heat an internal combustion engine creates. Most new vehicles have an optimum operating temperature of around 200 degrees Fahrenheit or about 93 degrees Celsius; water boils at 212 degrees Fahrenheit, or 100 degrees Celsius and freezes at 0 Celsius or 32 degrees Fahrenheit. That is where Anti-Freeze comes in; it is used as a stabilizer to help keep the mixture in the cooling system from boiling or freezing depending if the vehicle is in use. Anti-Freeze in a 50% mixture with water can change the freezing point from 32 degrees Fahrenheit or 0 Celsius, to –35 degrees Fahrenheit or – 37 Celsius. It moves the boiling point from 212 degrees Fahrenheit or 100 degrees Celsius to 223 degrees Fahrenheit or 106 degrees Celsius. Pressure is the second way that the boiling point is raised; most vehicles have between 13-15 psi (pounds per square inch) in the cooling system.

This can raise the boiling point of the fluid mixture approximately 45 degrees Fahrenheit or just over 7 degrees Celsius.

Water pump: The water pump is a mechanical or electric in some applications pump that circulates the engine coolant/anti-freeze through the radiator and back to the engine. Mechanical pumps are usually driven by an accessory drive belt or by the timing belt/chain. Look to see more electric pumps in future vehicles since the mechanical pump does rob horse power.

Thermostat: the t-stat is a temperature sensitive orifice in the cooling system that opens and closes according to engine temperature to regulate the flow of coolant/anti-freeze through the radiator and back to the engine. This allows for the engine to be run at specific temperatures to optimize the performance and emissions levels of the vehicle. Look for a PBT on t-stat's further in this article.

Radiator: The radiator is basically a box with tubing for the coolant to pass through that have many "fins" swedged on the OD of the tubing for thermal conductivity, typically mounted at the front of the vehicle. The coolant is driven through the tubing so that air may pass across the fins and cool the anti-freeze/coolant. The fins then act as thermal conductors to dissipate the heat. If a radiator is thermally efficient there will be a minimum of 20 degrees Fahrenheit and just over 3 degrees Celsius between upper and lower radiator hose. Even if the radiator has been flushed and flow checked, it does not mean that it is thermally effective. The fins that are swedged onto the flow tubes can lose their tension and no longer be the heat sync that they were designed to be. Temperature in vs. temperature out is the true testing measure if your radiator and cooling system is doing the job.

Cooling fan: The cooling fan is located directly behind the radiator, whether the vehicle is front or rear wheel drive. Its job is to pull air through the radiator at lower vehicle speeds to keep it from over-heating. Cooling fans can either be mechanical (belt driven on the engine) or electric (mounted on the radiator, temperature controlled)

Drive belts/hoses: All of the antifreeze/coolant in your vehicle is pumped through several hoses. Maintaining them is crucial to preventing serious engine damage from over-heating. Visually inspect the hoses for leakage, cracks or abrasions and the general integrity of the hose; they should be slightly pliable when squeezed with your fingers. Replace any that are questionable. The drive belt/belts should be inspected regularly as well.

Fig 1 Basic cooling system function and its components. Today's systems are closed loop and have an overflow reservoir.

I know that this information is basic and almost mundane but during this economic climate who if anyone is replacing or repairing anything on a vehicle unless it is broken or not working? The old adage "if it ain't broke don't fix it" seems to be very prevalent today.

All this brings me to what I want to talk about, as far as premature failures of remanufactured or new engines being installed into vehicles today. Back in the later part of the 80's through present day the design of vehicles took a turn into aerodynamic designs that would enhance fuel economy. The front of vehicles got lower and rounder. Bumpers per se disappeared and now became part of the frame structure with aerodynamic plastic covers, cab forward designs became common place and radiators are now typically much lower than the top of the engine. The problem with that is now filling a cooling system no longer is a simple task and the potential for air pocket hot spots is now common place.

Bleeding the cooling system refers to removing all air from the system. Air in the cooling system causes hot spots and subsequently overheating and can lead to serious engine damage. Bleeding the Cooling System becomes a critical part of an engine installation or if you replace a component such as a radiator hose, water pump, or radiator. In any of these cases, you musts take the time to bleed the cooling system to ensure that the air pocket hot spots do not occur. Overheating can readily be caused by air pockets existing in the cooling system obviously because air doesn't transfer heat anywhere close to the same rate as coolant. To help avoid air pockets, first try to fill the engine with coolant before filling the radiator or reservoir. This can often be done through a thermostat housing, and elbow or whatever may be available as a high point in the engine. Many of today's radiators may not even have a cap on them and the only access is through the reservoir tank. There is equipment available also that will actually draw coolant through the system via vacuum which is an excellent method.

Once the radiator or reservoir is filled, start the engine and turn the heat to max for the whole process of bleeding the cooling system. Turning the heat to max allows the coolant to circulate throughout the whole system and causes any air pockets to exit from the radiator. Then rev the engine to approximately 2,000 RPMs and hold for about 15 seconds. If you don't have an RPM gauge on your dashboard, simply push down slightly on the accelerator pedal until you hear that your engine is working slightly harder than it normally does at idle, but take care not to over-rev the engine. Do this about three times so that the coolant circulates quickly and so that it pushes out any air pockets that may cause overheating.

Many of today's vehicles also have bleeder valves that you can utilize to bleed the cooling system. Some thermostats have bleed holes in them also. Something that technicians have done is to drill and 1/8" hole in the thermostat to allow for air bleeding on a continuous basis. When you feel that you have bled the system completely install the radiator cap and drive the vehicle for about five to ten minutes or until it reaches operating temperature. Keep your eye on the temperature gauge and make sure that it doesn't pass the midway point. If the gauge is showing any signs of overheating repeat the bleeding process to ensure that you get all the air out of the system.

Why have I gone to these lengthy measures to talk about cooling system operation and air pocket hot spots because there continues to be a high insistence of premature engine failures that will have isolated piston scuffing on one side of the skirt (Fig 2). This was on the inboard side of the engine along the lifter valley the highest area of the coolant in the engine block. It also scored only one side of the cylinder Fig 3. Even though the piston was correct the cylinder bore was correct clearance was correct the piston and cylinder still scored due to an isolated hot spot of the cooling system. So what started out as a mundane lesson can provide you with valuable premature failure diagnosis. Cooling systems can be remanufacturer and manufacturers' greatest enemies if the installing technician does not follow proper bleeding procedures.

Fig 2 both views above are from the same piston, the scored skirt on the right was on the inboard side of the engine against the lifter valley the highest point of coolant in the engine where an air pocket caused and isolated hot spot and scored only one side of the piston.

Fig 3 the inside lifter valley side of the cylinder scored due to an air pocket hot spot in the cooling system.

The Essential Guide to Motor Oils

By Roy Berndt
Program Manager
PROFormance Powertrain Products

Everyone that has the misfortune of having to purchase a new or remanufactured engine is keenly aware of the major expenditure and investment being made to have this complex collection of components replaced in your vehicle. Think of anything that you would purchase for thousands of dollars, be it new washer and dryer, a new sound system or perhaps an in home theater system. What about a new riding mower or snow blower, fishing boat or Jet Ski, you are hoping and praying that this will be an investment that will last for a long time. So you read the manuals and you make certain that you do all the things that should be done so that you get a long and trouble free pay back. Well engines need to be treated the same way and there is one thing above all things that is the most important of all things that you can do to insure that you have that long term investment payback. OIL! Oil is the life blood of an engine and if it becomes anemic (broken down) or contaminated with plaque (dirt or combustion contaminants) your engine will have a heart attack (catastrophic failure) and you have just lost your investment capitol that you made into your means of transportation.

There are only a few basic reasons why it is necessary to change your oil, and they all, in the end, have to do with decreased protection of your engine and decreased performance. If these elements can be minimized, then there would be little or no reason to change the oil.

First off, all oil breaks down. That generally will include basestocks and additives. Without focusing on performance characteristics, the most significant difference from one oil to another is how quickly breakdown occurs. Although there are many factors that contribute to the breakdown of an oil, heat is one of the most important. Depletion and decreased effectiveness of oil additives is also important, but that will be discussed later.

Petroleum oil begins to break-down almost immediately. A high quality synthetic, on the other hand, can last for many thousands of miles without any significant reduction in performance or protection characteristics. Synthetics designed from the right combination of basestocks and additives can last almost indefinitely with the right filtration system.

Flash point is the temperature at which an oil gives off vapors that can be ignited with a flame held over the oil. The lower the flash point the greater tendency for the oil to suffer vaporization loss at high temperatures and to burn off on hot cylinder walls and pistons.

The flash point can be an indicator of the quality of the base stock used. The higher the flash point the better. 400 degrees F is the absolute MINIMUM to prevent possible high consumption.

Even the best petroleum oils will have flash points only as high as 390 and 440 degrees F. Some actually have flashpoints as low as 350 degrees. For today's hot running engines, this is not nearly enough protection. Just

about any synthetic you come across will have a flashpoint over 440 degrees. Premium synthetics can have flashpoints over 450 degrees with some even reaching as high as 500 degrees. That's a big difference.

Thus, it becomes important to discuss the manner in which petroleum and synthetic oils burn off. As a refined product, petroleum oil molecules are of varying sizes. Thus, as a petroleum oil heats up, the smaller, lighter molecules begin to burn off first.

Since the ash content in many petroleum oils is higher than synthetics, deposits and sludge are left behind to coat the inside of your engine. Detergent and dispersant additives are used to keep these deposits to a minimum, but only so much can be done. Unless you're changing a petroleum oil every 2,000 to 3,000 miles some deposits are going to be left behind.

In addition, as smaller particles burn off, the larger, heavier molecules are all that is left to protect the engine. Unfortunately, these larger particles do not flow nearly as well and tend to blanket the components of your engine which only exacerbates the heat problem.

Synthetic oils, on the other hand, because they are not purified, but rather designed within a lab for lubrication purposes, are comprised of molecules of uniform size and shape. Therefore, even if a synthetic oil does burn a little, the remaining oil has the nearly the same chemical characteristics that it had before the burn off. There are no smaller molecules to burn-off and no heavier molecules to leave behind.

Moreover, many synthetics have very low ash content and little if any impurity. As a result, if oil burn-off does occur, there is little or no ash left behind to leave sludge and deposits on engine surfaces. Obviously, this leads to a cleaner burning, more fuel efficient engine.

Synthetics do a much better job of "cooling" engine components during operation. Because of their unique flow characteristics, engine components are likely to run 10 to 30 degrees cooler than with petroleum oils. This is important, because the hotter the components in your engine get, the more quickly they break down.

Most people understand that at cold temperatures, an oil tends to thicken up, and many people know that synthetics do a better job of staying fluid. However, many people don't realize why petroleum oils tend to thicken up. More importantly, though, they don't realize that this thickening process can wreak havoc on their oil. Because most petroleum oils contain paraffin (wax), they tend to thicken up considerably in cold temperatures. Therefore, in order to produce a petroleum oil that will perform adequately in severe cold temperatures, additives called pour point depressants must be used in high quantities. These additives are designed to keep the wax components of a petroleum oil from crystallizing. This maintains decent flow characteristics in cold weather for easier cold starts.

In areas where the temperature remains below zero for any period of time, these additives are used up very quickly because petroleum oils are so prone to wax crystallization. As a result, the oil begins to flow less easily in cold weather temperatures. Of course, the result is harder cold starts and tremendously increased engine wear. Thus, the oil must be changed in order to provide the cold weather engine protection which is necessary.

Synthetic oils, on the other hand, contain no paraffin. Therefore, they need NO pour point depressant additives. In addition, even without these additives, synthetics flow at far lower temperatures than petroleum oils. For instance, very few petroleum oils have pour points below -30 degrees F. Many synthetic oils, without any pour point depressants, have pour points below -50 degrees F. That's a big difference. There is, in fact, one oil on the market that has a pour point of -76 degrees F.

Since synthetics do not have any pour point depressants, there is no chance of these additives breaking down or being used up over time. There are no additives to break down. Therefore, synthetic oils maintain their cold temperature flow characteristics for a very long time. As a result, there is one less reason to change the oil if using synthetic as opposed to petroleum.

In addition, another part of cold weather driving that is extremely tough on an oil is condensation. Because it is so cold, it takes a fairly long drive to get the engine warm enough to burn off the condensation that occurs inside the engine. As a result, vehicles routinely driven short distances in cold weather will build up condensation within the oil. If left to do its dirty work, this water would cause acids to build up within the oil and corrosion would begin within your engine.

So, there are additives in the oil which are designed to combat these acids. Generally, the TBN value of an oil will be a good determination of how well and for how long an oil will be able to combat these acids. Most petroleum oils have TBN numbers around 5. Most synthetics have TBN levels over 8 or 9. Premium synthetic oils (especially those designed specifically for extended oil drains) will have TBN numbers around 11 to 14. This allows for much better acid control for a much longer period of time, thus decreasing the need for an oil change due to cold temperature condensation.

It is true that the additives in many oils begin breaking down after only a few thousand miles. What needs to be recognized is that there are different quality "grades" of additives just as there are different quality grades of just about any other product that you buy. There are also different combinations of additives that tend to work for better and for longer when combined than when used individually.

1. VISCOSITY RETENTION -- Shear stable viscosity index improvers help premium synthetic motor oils maintain their viscosity in the range appropriate to each grade over extended drain use. Conventional oils formulated with easily sheared viscosity index improvers often drop out of viscosity specification relatively quickly -- sometimes even before the end of a 3,000-mile oil drain interval. Viscosity loss leaves oils incapable of protecting engines from metal to metal contact and wear in high temperatures.

2. CONTAMINANT CONTROL -- Dispersants keep contaminants, including combustion by-products, suspended in oil. The rate of dispersant depletion depends on the motor oil's additive treat- rate and the oil's contaminant load. Premium synthetic motor oils are formulated with high additive treat rates specifically to allow extended drain intervals.

3. ACID CONTROL -- Total Base Number (TBN) describes the acid neutralization ability of an oil, with higher TBN oils providing longer lasting acid neutralization. Most passenger car motor oils are formulated with TBN of 5

to 7. Many synthetic motor oils are formulated with 9-11 TBN or higher. The result: longer and better acid neutralization capability allowing for extended drain use.

There is also the issue of contamination. Oil will be contaminated in three major ways.

One will be through debris that comes in through the air intake. Once it makes it through the air filter, it ends up in your oil. Once in your oil, it starts damaging your engine.

The second source of contamination will be metal shavings from the inside of your engine. The lesser the quality of the oil, the higher percentage of these shavings because there will be more metal to metal contact inside the engine.

The third source of contamination will be from combustion by- products. Combustion by-products will generally raise the acidity of your oil, which causes corrosion in your engine. In addition, they will be left behind as the engine oil burns off and will collect on the inside of your engine as deposits. To maintain the viability of your oil as well as protection of the engine, the contaminants have to be removed/neutralized.

One of the best ways to help with this process is to keep most of the contaminants from ever getting inside the engine in the first place. That's where your air filter comes in. Conventional paper air filters are pretty worthless. How many times have you removed your air filter for replacement only to find that you could write your name in the dust that collected around the air intake? That's just the stuff that was left behind. Imagine the amount that actually ended up inside the engine.

Part of the problem is that traditional paper filters do not fit all that snugly in the air intake compartment. They've improved, but they're still not great. More importantly, though, they let way too much debris shoot right through the filter element itself. As a side-note, they do not provide for very good air flow either.

You see, as a compromise to allow enough air flow for your engine to run "properly", surface type air filtration media have to allow certain sized particles to flow through. If they made the filtration media any more tightly woven, not enough air would pass through quickly enough to keep your vehicle running.

As a result, most paper filters won't catch anything smaller than about 20 to 40 microns with any real efficiency. In most cases, the more expensive the filter, the lower the micron level of filtration - and the lower the better, of course.

20 to 40 microns is pretty small. A human hair is about 100 microns in diameter. The problem is that 60% of engine wear is caused by particles between 5 and 20 microns (most likely because there is so much more of it). If you don't keep that stuff out, it'll eat away at your engine.

Ok, so we've taken care of the air intake, but what about metal particles from engine component wear? Well, there are a couple of things going on here that lead to better protection from a synthetic oil. One aspect that proves to be very important is cold weather starts.

The pour point of an oil is 5 degrees F above the point at which a chilled oil shows no movement at the surface for 5 seconds when inclined. That's tech-talk which basically means that the pour point of an oil is the point at which it ceases to be "pourable". This measurement is especially important for oils used in the winter.

A borderline pumping temperature is given by some manufacturers. This is the temperature at which the oil will pump and maintain "adequate" oil flow and pressure within an engine. This is not provided by a lot of the manufacturers, but generally seems to be about 20 degrees F above the pour point. So, the lower the pour point the better.

Most petroleum oils have pour points in the range of -15 to -35 degrees F. That means that their borderline pumping temperature is, at best, around -15 degrees F and probably closer to 5 to 10 degrees F. So, if you're running a petroleum oil, don't expect to go out and start your car at 0 degrees and have it purr like a kitten. It's going to spit and sputter and kick and scream for a few minutes.

Synthetic oils, on the other hand, routinely have pour points around -40 degrees or colder. Some have pour points as low as - 60 to -70 degrees F. Granted, there are very few of us who will ever have to start our car at this temperature, but imagine how well these oils lubricate at -20, if it they still flow at -70.

Generally, a thin film of synthetic oil will remain on engine components for days after it was last run. Petroleum oils tend to drain back down to the oil pan very quickly, leaving no oil film to protect your engine at start-up. Many auto techs and backyard mechnics can attest to this after doing engine tear- downs. Those using synthetic oil generally will have a thin film of oil left on components even if the engine has been sitting for awhile.

It's certainly not impenetrable, and I wouldn't go draining your oil after installing 6 quarts of synthetic just to see if your engine still runs, but it does serve a purpose. Your engine should virtually NEVER see metal to metal contact, whether in hot or cold climates. That's something that a petroleum oil can't do.

In addition, because of the higher film strength and better lubricity characteristics of synthetic oils, they routinely perform better on standardized ASTM wear scar tests. This would indicate a higher level of engine protection and would certainly lead to fewer engine wear particles in an engine. Hence, fewer contaminants in the oil to necessitate changing it.

Only one type of contaminant left to discuss: combustion by- products. These little buggers can wreak havoc in an engine. Not only can they form deposits on the inside of an engine which will rob it of performance and, ultimately, life expectancy, they will also tend to raise the acidity of the lubricant.

Higher acidity levels in your oil can lead to severe corrosion and break-down of engine components. In turn, this break-down leads to more oil contaminants and the necessity for an oil change.

Three things keep these contaminants in check: the TBN of the oil, high efficiency oil filtration and tight ring seal. The most important of these three is ring seal. If the number of combustion by-products entering your oil can be reduced, there will be less necessity to remove or neutralize them.

Poor ring seal allows combustion by-products to pass from the combustion chamber into the crankcase where they contaminate the oil. Tight ring seal keeps them out. Synthetic motor oils encourage a tighter ring seal than petroleum motor oils do.

As we discussed earlier, TBN (total base number) is a measure of how well a lubricant can neutralize acidic combustion by- products. The higher the TBN, the better the protection against these acidic by-products and the longer that protection will last. Hence, the possibility of longer oil drain intervals with oils that have high TBN values.

Oil filtration is the last component that must be discussed when making the case for extended oil drains. The next section in this series addresses this critical component.

First of all, the statistics previously mentioned regarding engine wear haven't changed. 60% of all engine wear is caused by particles between 5 and 20 microns. Unfortunately, most oil filters on the market today are lucky to remove even a small percentage of particles under 30 to 40 microns. This, again, leaves most of the harmful debris in your oil.

The actual filtration efficiency of a particular filter really depends upon the filter manufacturer, and it is sometimes very difficult to get any specific numbers from them regarding their filters' actual filtration efficiency.

So, most companies have gotten away from micron ratings (to avoid confusion) and have gone to an overall efficiency rating. In other words, an industry standard test is used in which oil is contaminated with a certain number of particles of varying micron sizes. At the end of the test, there is a measurement taken to determine the total percentage of ALL of these particles that were removed by the filter. That percentage is then stated as the overall filtration efficiency of the filter.

Some companies use a single pass test, others use a multiple pass test. Both are perfectly valid and will give you an excellent way of determining how well a filter will do its job, but you should not try to compare results from a single pass test to results of a multiple pass test. You'd be comparing apples and oranges. In either case, high efficiency filters will rank in the low to mid 90's for filtration efficiency. Off-the- shelf filters will rank in the mid 70's to mid 80's for filtration efficiency.

The fact is, you would probably be amazed at how much engine wear could be eliminated simply by using more advanced oil filtration. In paper 881825 the Society of Automotive Engineers indicates that a joint study was performed between AC Spark Plug and Detroit Diesel Corp. The study found that finer oil filtration significantly reduced the rate of engine wear.

According to the paper, the tests regarding engine wear within a diesel engine were performed using four levels of oil filtration. They chose filters whose efficiency rating was very high for particles of 40 micron, 15 micron, 8.5 micron and 7 micron sizes.

The same was done for gasoline engines, except that the relative sizes were 40 microns, 30 microns, 25 microns and 15 microns.

To make a long story short, the researchers had this to say:

"Abrasive engine wear can be substantially reduced with an increase in filter single pass efficiency. Compared to a 40 micron filter, engine wear was reduced by 50 percent with 30 micron filtration. Likewise, wear was reduced by 70 percent with 15 micron filtration."

By combining this type of oil filtration with the superior protection and cleanliness of a premium synthetic oil, you will virtually eliminate engine wear.

For those of you who just want to know what's best, here's a breakdown of the top 3, in based upon my findings. Mobil 1, Pure 1 and AMSOIL provide the greatest filtration efficiency in the tests results that I found. Mobil 1 and Pure 1 both achieved 93% overall filtration efficiency on the SAE HS806 test. AMSOIL scored a 94%.

In regards to filtration capacity, the AMSOIL outscored them by a wide margin. In a comparison of filters recommended for the same application, the AMSOIL could hold 21 grams of particulate matter. Comparable filters from Mobil 1 and Pure 1 held 18 grams and 15 grams respectively. So, the AMSOIL filter held 17% more than the Mobil 1 and 40% more than the Pure 1.

The AMSOIL company recommends changing their filters at 12,500 mile or 6 month increments. Based on their numbers, this seems reasonable. They have better capacity and stronger construction which should allow them to achieve longer change intervals. Since AMSOIL filters have been recommended for these intervals for about 20 years, it seems reasonable that they know what they're talking about.

Mobil 1 and Pure 1 recommend changing their filters at your vehicle manufacturer's recommendations. That generally means change the filter at each oil change which amounts to changing the filter every 3,000 to 7500 miles depending upon driving conditions. Because of the lower capacity of the Pure 1 filters, I'd recommend changing them closer to 3 to 5,000 miles. The Mobil 1 would probably last 5,000 to 7500 miles with good results.

As a side note, you can determine if your oil is bypassing your oil filter by touching your filter after at least 45 minutes to an hour's worth of driving. If the filter is hot, you're probably in good shape. If it's not, the oil is likely bypassing the filter, and it is time for a change.

This is probably way more information about oil that you would ever want to know but as you can see there are a lot of different ways that you can maximize the protection of your engine. The type of oil, oil filter and air filter can all be part of whether or not your engine is going to last a long trouble free time.

Ford 4.0L SOHC Timing Component Timing Identification Can Be Tough

By Roy Berndt
Program Manager
PROFormance Powertrain Products

For those of you that have not come across or had the privilege of working on the Ford 4.0L SOHC cam engine you are about to get a baptism in its proliferation in the timing components used. Now before you go off and wonder why I am even trying to tell you about these, know this there are none available in the aftermarket (or at least not that I was able to find). You can buy tensioners, guides and chains but gears are not available from the aftermarket and as you see the proliferation you will understand why. So you will either have to purchase them new from Ford or you are going to reclaim those that are not worn or damaged.

The 4.0L SOHC engine come on the scene in 1997 and is still used in current production. There are some variations of this engine between the 2WD and 4WD engines in that the 4WD uses a balance shaft assembly where the 2WD does not. This engine has been used in the Ranger/Mazda B Series, Explorer, Mountaineer, Mustang and Land Rover.

The SOHC engine has a unique variation to the manner in which it drives the camshafts. Since this engine is part of the original Cologne, Germany design it actually started out as a V-4, OHV engine back in the 60's that evolved into a V-6 OHV configuration of the 2.8L and 2.9L that many of you should remember probably not very fondly based on the amount of cylinder heads that seemed to always crack. By the time it got to the 4.0L SOHC the camshaft area of the block now houses a jack shaft. The jackshaft is used in place of a camshaft to drive a timing chain to each cylinder head. Three timing chains are used, one from the crank to the jackshaft, one in the front of the engine to drive the cam for the left bank, and one on the back of the engine to drive the cam for the right bank. Not what most of us are accustomed to seeing, and better yet there are no keyed or doweled indexing points on any of the camshafts. There are fixtures/tooling available to hold the camshafts in place at which time you install the gears and torque them into position.

If all that has not made you feel as though you are not interested in working on this engine lets jump into the timing gears and their differences so that when you do cross over into the dark side you will have enough ammunition to survive. Let's start with the 1997 through 2001 engines and show you the differences between them.

The 2WD engine will have a crankshaft gear that has approximately .068" raised area on the gear face, and will carry a number stamping of 97, 98, 99, 00 or 01 on it (Fig1). The two wheel drive timing application does not use any type gear spacer/sprocket for driving the balance shaft assembly since it is not used.

The gear used with the front cam gear has the same numbers stamped on to it as the crank gear (97 thru 01) as seen in (Fig 2).

The 1997 to 2001 4WD application uses a crankshaft gear that is completely flat and has no raised edge on it and has the same numbers stamped into it as did the 2WD gear 97-01 (Fig 3). Since the 4WD application utilizes a balance shaft assembly at the bottom of the engine it also uses spacer/sprocket off the crank snout to drive its chain. (Fig 4) The 4WD engine implements the same Cam gear as the 2WD as seen in Fig 2

Now we enter the 2002 thru current production timing gears and going in the same order as above we will start with the 2WD engine applications. The crank gear on these 2WD applications has a .138" ledge on it and carries the number 2L2E-6306-BA (FIG 5). This gear employees the use of the Cam gear that has the numbers 02 or 03 stamped on it as shown in (Fig 6) it is also the same cam gear that is used for the 4WD applications.

Lastly there is the crank gear that is used for the 4WD application from 2002 to current and it has a .078" raised edge upon it and carries the number 2L2E-6306-AA (FIG 7). Take note that the only difference in the markings of the 2WD and 4WD 02 and up gears are the suffix numbers AA and AB do not get caught looking at only the prefix numbers or you will use the wrong gear in the wrong combination. The cam gear is the same as the 2WD (FIG 6) and the same balance shaft drive gear in (FIG4).

So this is how it all lays out and I guess you can see why the aftermarket has chosen not to deal with the proliferation. Use the wrong ones in the wrong place and you will have chain and guide issues in an engine that has its share of problems along those lines already. I have to give credit where credit is due and this information would not have been possible without the help and input of Chris Roberts, my co-worker at PROFormance Powertrain Products.

Fig 1 1997-2001 2WD Crank gear with .068 raised shoulder (arrow) and # 97, 98, 99, 00 or 01 stamped onto the gear (red circle)

Fig 2 1997-2001 2WD and 4WD Cam gear with # 97, 98, 99, 00 or 01 stamped onto the gear (red circle)

Fig 3 1997-2001 4WD Crank gear with no raised shoulder (arrow) and # 97, 98, 99, 00 or 01 stamped onto the gear (red circle)

Fig 4 1997 thru current production balance shaft drive sprocket/spacer used with flat crank gear (97-01)that has no raised edge or the .078" raised edge gear (02 thru current)

Fig 5 2002 to current 2WD Crank gear with .138" raised shoulder (arrow) and 2L2E-6306-BA stamped onto the gear (red circle)

Fig 6 2001 to current 2WD and 4WD Cam gear with # 02 or 03 stamped onto the gear (red circle)

Fig 7 2002 to current 4WD Crank gear with .078" raised shoulder (arrow) and 2L2E-6306-AA stamped onto the gear (red circle)