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Coolants Tom Birch Jim Halderman 1 Introductions: Tom Birch Retired instructor from Yuba College, Marysville, CA. Author of many automotive textbooks Former officer in CAT and NACAT Board Member Introductions: Jim Halderman
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Coolants Tom Birch Jim Halderman Tom Birch, 3/07 1
Introductions: Tom Birch • Retired instructor from Yuba College, Marysville, CA. • Author of many automotive textbooks • Former officer in CAT and NACAT Board Member
Introductions: Jim Halderman • Former flat-rate technician and instructor and a business owner. Author of many automotive books and lives in Dayton, Ohio. • http://jameshalderman.com
Topics to be Discussed • Purpose and function of engine coolants • Principles and details about water quality • Types of coolants • pH testing and importance • Cooling system testing and service procedures
What is Coolant? Additives: About 3% Coolant is a mixture of: 1. Water (50%) 2. Freeze depressant (Usually ethylene glycol-about 93%) 3. Corrosion inhibitors (additives) Ethylene Glycol: 47% Water: 50% Coolant 5 Need to know
Water Water is the principal ingredient and: 1. Is inexpensive 2. Is a very efficient heat exchange fluid 3. Has excellent thermal conductivity 4. Has a good specific heat 5. Freezes at 32°F (0°C) 6. Boils at 212°F (100°C) The water used in coolant must be clean & pure. 6 Need to know
Good Water The American Society for Testing and Materials (ASTM) standards for water quality include: Chloride <40 ppm Sulfate <100 ppm Calcium <100 ppm Magnesium <100 ppm Total Hardness <170 ppm pH Range: 5.5—9.0 Iron <1 ppm 7 Nice to know
Good Quality Water • Good quality water types include: • Deionized • Distilled • Demineralized • Purified 8 Need to know
City Tap Water • Usually unknown quality • Can have unwanted chlorides, minerals, or salts • Unknown pH Need to know
What to do? Test the water at the shop and if it has high mineral content, consider: 1. Purchasing distilled or de- mineralized water 2. Installing a micro filtration system 3. Installing a reverse osmosis system Need to know
Burst Pressure Water expands when it freezes, and this creates the burst pressure that can break cooling system components. Antifreezes (freeze depressants) lower the freeze temperature. 11 Nice to know
Pure Water 50/50 Anti-Freeze/Water 70/30 Anti-Freeze/Water Freezing Point 0° C (32° F) -37° C (-35° F) -55° C (-67° F) Boiling Point 100° C (212° F) 106° C (223° F) 113° C (235° F) Freeze & Boil 12 Need to know
Ethylene Glycol Ethylene glycol is the base antifreeze used in every OEM factory fill. The additive package will vary. Need to know
Propylene Glycol • Only sold to the aftermarket • Not recommended for use by vehicle manufacturers • More expensive than EG, Increased cost is $/gallon • Still toxic but is not as sweet as EG Need to know
Poison 15 Need to know
MSDS 16 Need to know
Embittered Coolant Embittered = tastes awful Embittering agent is required (denatonium benzoate, 30 ppm) Required in California and Oregon since 2004 but not included on the label. Need to know
Additives The major additives: 1. reduce corrosion 2. buffer pH 3. add color (dye) 18 Need to know
Color The color helps us identify a coolant leak. It also helps us identify the additive package. Should not be used as an indicator what to use-some Chrysler vehicles used HOAT coolant that was green 19 Need to know
IAT Inorganic Additive Technology (IAT) is the traditional green coolant used in most older vehicles. This solution offers fast-acting corrosion protection, but the additives are quickly consumed, exposing the cooling system to possible corrosion problems if not changed regularly. Need to know 20
IAT antifreeze can contain: Silicates (possible abrasive dropouts) Phosphates Borates IAT (Usually Green in Color) IAT is considered obsolete and can cause early failure of ceramic-phenolic seals used in newer water pumps. 21 Need to know
OAT (Usually Orange) Organic Acid Technology (OAT) is the formula found in DEX-COOL®, and is usually the antifreeze/coolant of choice for GM, VW, and many Japanese/Asian vehicles. This formula is engineered to offer long-life corrosion protection. The downside of OAT is it is not compatible with other types of coolant (IAT and HOAT). In fact, Ford, Chrysler and others say to not use this type of coolant in their newer models. 22 Need to know
OAT-continued NAPS=nitrates, amines, phosphate and silicate free Nice to know
OAT=DEX-COOL is one brand Nice to know
DEX-COOL Concerns • Root cause seems to be air entering system past the cap and leaking intake manifolds • Replace cap and check cap seats if radiator contains air • Air causes rust of cast iron and formation of ‘Brown Gunk’ • Rust then causes blockages Need to know
Rust in Engine Need to know
GM DEX-COOL Problems • Class action suit; GM may have to pay for intake gaskets on V-6s (V-8s still being determined) Brown Gunk on radiatorcap Need to know
DEX-COOL’s Unique Formulation • DEX-COOL uses Ethylhexanoic Acid (2-EH) as a corrosive inhibitor • 2-EH is prone to damage plastics like Nylon 6.6 used in intake manifold gaskets and radiators • G30 OAT and Peak Global OAT do NOT use 2-EH Nice to know
HOAT (Many colors) Hybrid Organic Acid Technology (HOAT) is found in newer Ford, Chrysler and Mercedes vehicles. Said to use the very best aspects of both IAT and OAT, HOAT is a very protective, long-life coolant. 29 Need to know
HOAT=Red; Pink; Yellow or Blue Nice to know
“G” Designations • G= Glysantin –trade name of BASF. Valvoline (Zerex) in the US. • G30 and G34= non-silicate and phosphate free • G05 = different from Texaco’s DEX-COOL, G05 product contains from 252 to 308 PPM Silicon which Valvoline believes provides a better aluminum protection Nice to know
“G” Designations-continued • G11=Blue VW used before 1997 • G12=Pink/Red VW 1997+ • G12=Purple VW 2003+ • HOAT formulation; phosphate free ?
“G” Designations-continued • G48=Low Silicate and Phosphate free • Blue Color • NAP =nitrates, amines, phosphate free • BMW ?
Replacement Antifreeze The best choice is to follow the vehicle manufacturer’s recommendations. OR, you can follow the recommendations of reliable antifreeze manufacturers (next slide). Need to know
Substance pH Hydrochloric acid -1.0 Battery acid 0.5 Lemon juice 2.4 Cola 2.5 Vinegar 2.9 Orange or Apple juice 3.5 Acid Rain <5.0 Tea or healthy skin 5.5 Milk 6.5 Pure water 7.0 Healthy human saliva 6.5 – 7.4 Blood 7.34 – 7.45 Sea water 7.7 – 8.3 Hand soap 9.0 – 10.0 Household ammonia 11.5 Bleach 12.5 Household lye 13.5 Caustic Soda 13.9 pH Acid pH is a measure of acidity or alkalinity of a solution. Less than 7 is considered acidic. Greater than 7 is considered alkaline. Alkaline 36 Nice to know
pH Effects Fresh antifreeze should have a pH between 9 and 11, used between 7.5 and 10. Antifreeze tends to become more acidic over time. Excessively acidic or alkaline coolant will cause corrosion of cooling system components through galvanic action. It can also increase electrolysis; the dissimilar metals in contact with an electrolyte can produce a simple battery. 37 Need to know
pH of various coolants • IAT= 9.0-10.5 new • OAT= 7.5-8.5 new (G30 and G34 designation) • HOAT= 7.5-8.5 new (G05,G48,G11 or G12 designation) Need to know
Desired pH Need to know
Conventional Antifreeze Compounds 40 Nice to know
Extended Life Antifreeze Compounds 41 Nice to know
Coolant Summary • Ethylene glycol - Most ethylene glycol coolant is any color and contains about 93% ethylene glycol plus water and additives. • Propylene glycol- less harmful to pets and animals because it is not sweet tasting, although it is still harmful if swallowed. • Organic acid technology (OAT) antifreeze coolant – This type is ethylene glycol based but it does not contain silicates or phosphates. It is usually orange. DEXCOOL is an OAT coolant. • Hybrid organic acid technology (HOAT) – This orange,green, red, blue or yellow coolant is an ethylene glycol based coolant similar to the OAT- type antifreeze as it uses additives (a low amount of silicate) • VW/Audi pink - Most of these coolants are HOAT (ethylene glycol-based with • some silicate and contain an organic acid) and are phosphate free. • Asian red– This coolant is ethylene glycol-based and is silicate-free, yet contains phosphate. • Mercedes and Ford yellow – This conventional ethylene glycol coolant has low amounts of silicate and no phosphates. • Mercedes Lifetime – Very expensive, can be drained, filtered and reused. • Korean or European blue – This conventional ethylene glycol coolant has low amounts of silicate and no phosphates. Nice to know
Coolant Related Problems 43 Need to know
Corroded Water Pump One of the reasons for the removal of silicates from coolant Need to know
Corroded pump can cause: • reduced coolant flow and an overheating condition Need to know
Cavitation Cavitation Cavitation is the sudden formation and collapse of low-pressure bubbles. With gasoline engines, the pressure drop can occur at the inlet of the water pump. These bubbles produce a pitting of the solid metal . 46 Need to know
Cavitation Damage The very low pressure can produce gas bubbles that implode next to a metal surface. The implosion blasts particles from the surface. Need to know
Diesel Wet Sleeve Cavitation The sleeve can vibrate during the combustion stroke producing the pressure drop, bubbles, and metal erosion. Heavy duty coolants contain supplemental coolant additives (SCA) to help prevent this. Need to know
Corrosion Common corrosion is the “decomposition of metal” and is commonly called rust, an iron oxide that forms on iron components. Corrosion is also aluminum oxide, the whitish material that forms on aluminum components Oxide formation eats away at the parent material from the outside, and it also forms an insulating barrier for heat transfer. 49 Need to know
Corrosion aluminum oxide, often found on coolant outlet/stat cover 50 Need to know