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11
Coolants
22
What is Coolant?
Coolant is a mixture of: 1. Water (50%)
2. Freeze depressant (Usually ethylene glycol-about 93%)
3. Corrosion inhibitors (additives)
Water: 50%
Ethylene Glycol: 47%
Additives: About 3%
Coolant
Need to know
33
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.
Need to know
44
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
Nice to know
55
Good Quality Water
Good quality water types include:
• Deionized
• Distilled
• Demineralized
• Purified
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6
City Tap Water
Usually unknown quality Can have unwanted
chlorides, minerals, or salts Unknown pH
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7
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
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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.
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99
Freeze & Boil
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)
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10
Ethylene Glycol
Ethylene glycol is the base antifreeze used in every OEM factory fill. The additive package will vary.
Need to know
11
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
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1212
Poison
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1313
MSDS
Need to know
14
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
1515
Additives
The major additives:
1. reduce corrosion
2. buffer pH
3. add color (dye)
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1616
ColorThe 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
Need to know
17Need to
know 17
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.
1818
IAT (Usually Green in Color)
IAT antifreeze can contain: Silicates (possible
abrasive dropouts) Phosphates Borates
Need to know
IAT is considered obsolete and can cause early failure of ceramic-phenolic seals used in newer water pumps.
1919
OAT (Usually Orange)
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.
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.
Need to know
20
OAT-continued
NAPS=nitrates, amines, phosphate and silicate free
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21
OAT=DEX-COOL is one brand
Nice to know
22
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 blockagesNeed to know
23
Rust in Engine
Need to know
24
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 radiator cap
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25
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
2626
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.
Need to know
27
HOAT=Red; Pink; Yellow or Blue
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28
“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
29
“G” Designations-continued
G11=Blue VW used before 1997 G12=Pink/Red VW 1997+ G12=Purple VW 2003+ HOAT formulation; phosphate free
?
30
“G” Designations-continued
G48=Low Silicate and Phosphate free
Blue Color NAP =nitrates, amines, phosphate
free BMW
?
31
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
32
Antifreeze Applications n
3333
pH
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 is a measure of acidity or alkalinity of a solution. Less than 7 is considered acidic. Greater than 7 is considered alkaline.
Alkaline
Acid
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3434
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.
Need to know
35
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
36
Desired pH
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3737
Compound Purpose
Ethylene Glycol Lower freeze point, Raise boil point
Conventional Antifreeze
Block Polymers Defoamant & Scale & Deposit Control
Borate Iron protection & pH control
Nitrate Aluminum & solder protection
Nitrite Cast iron & steel protection
Mercacaptobenzothiazole (MBT) & Tolytriazole (TT)
Copper & brass protection
Phosphate Iron protection & pH control
Silicate Aluminum corrosion protection
Conventional Antifreeze Compounds
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3838
Compound Purpose
Nitrite Cast iron & steel protection
Modified silicone Defoamant
Defoamant
Borate Iron protection & pH control
Molybdate Iron corrosion protection
Potassium soap of Dibasic Carboxylic Acid
Iron, solder, and aluminum protection
Potassium soap of Dibasic Monobasic Carboxylic Acid
Aluminum and iron (with sebacate) protection
Phosphate protection & pH control
Tolytriazole (TT) Copper corrosion protection
Extended Life Antifreeze Compounds
Nice to know
39
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.
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4040
Coolant Related ProblemsProblem Appears as: Caused
by: Prevented by:
Cavitation Water pump impeller pitting
Low pressure at
impeller
Good coolant & Cooling system pressure
Corrosion Rust & pitting Acidic coolant
Good coolant
Erosion Inside-out wear
Dirty coolant
Good coolant
Electrolysis
Inside-out pitting
Acidic coolant & Stray current
Good coolant & Proper electrical grounds
Scale White coating Bad water Good waterNeed to know
41
Corroded Water Pump
One of the reasons for the removal of silicates from coolant
Need to know
42
Corroded pump can cause:
reduced coolant flow and an overheating condition
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4343
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 .
Cavitation
Need to know
44
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
45
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.
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4646
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.Need to know
4747
Corrosion
aluminum oxide, often found on coolant outlet/stat cover
Need to know
48
Metal Corrosion
This iron tube has been ruined by rust.
Need to know
49
Galvanic action
Galvanic activity does not require an outside source of voltage
The higher the conductivity of the coolant, the greater the amount of corrosion
Need to know
50
Metals
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51
Bi-Metal Corrosion
Ions move from more active metals to less active metal through the coolant which acts like the electrolyteNice to know
5252
Electrolysis
Electrolysis requires the use of an outside voltage source.
When electrical ions move from metal to the coolant, they can take metal atoms with them. This metal transfer can eat holes in a heater core or radiator. Electrolysis holes will usually start from the inside and have a dark coloration.
Need to know
53
Scale
The oil cooler in this radiator tank is covered with white scale. The scale caused the transmission fluid to overheat, and this contributed to early transmission failure.
If the ECT sensor received a scale coating like this, what would happen to engine and transmission performance?
Need to know
54
Coolant Tests
Normal coolant tests include: Visual Inspection: should be clean and bright Freeze Point: high boiling point indicates
dilution pH: wrong pH indicates buffer loss Coolant Voltage: high voltage indicates wrong
pH or stray current flow Miscellaneous or Fleet Concerns
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55
Depletion Rate of Additives
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56
Coolant Condition
This “green” antifreeze has a clean, bright appearance. The other types will have a different color but should also appear clean and bright.
A muddy brown or rust-reddish color indicates that corrosion is occurring.
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57
Freeze Protection, Refractometer
A few drops of coolant are placed under the sample window. The technician then holds the unit up to light and looks through the eye piece (right end).
Sample Window
Eye Piece
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58
Refractometer Image
The image will show the amount of freeze protection and is read at the scale at the bottom edge of the shadow. This unit can check EG and PG antifreeze freeze protection and battery specific gravity.
Shadow
Read Here
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5959
Freeze Protection, Test Strips
Test strips will change color when they are dipped into the coolant, and the color change is compared to the container.
Test strips are fairly accurate, easy to use, and inexpensive.
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60
Coolant Corrosion Protection
The new test strip color is compared to the color pads on the container to determine the amount of freeze protection and corrosion protection.
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61
Freeze Protection, Hydrometer
? Accuracy
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62
Can you trust this?
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63
Testing Coolant with a Voltmeter
This test gives variable and questionable results depending on many factors
Galvanic=less than 200 mV Electrolysis= (engine running and
accessories switched on and off)=less than 300 mV. This check can locate faulty ground connections
Need to know
64
Radiator Voltage
Connect the negative voltmeter lead to a good ground (this radiator has a plastic filler neck), and immerse the positive lead into the coolant. A reading of 0.300 V or greater indicates corrosion is probably occurring.
Need to know
65
pH Tests
pH can be measure using test strips or a meter.
Fairly accurate and costs pennies/test.
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66
pH Meter
This Milwaukee is probably more accurate and cost $30.00.
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67
Coolant Replacement
About 15 to 20% remains in the system after it has been drained
Fill system with antifreeze first and top off with water
Or use premixed coolant for good results, and adjust to 50-50 mix
Be sure to use the specified coolant GM warns not to reuse coolant drained
from the system
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68
Coolant Replacement-#2
Check the pressure cap and radiator for faults Check all hoses and always use coolant hose
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69
Ford Specifications
Yellow-colored Motorcraft Premium Gold Engine Coolant, meeting Ford specification WSS-M97B51-A1.* Green-colored Motorcraft Premium Engine Coolant, meeting Ford specification ESE-M97B44-A.* Orange-colored Motorcraft Specialty Orange Engine Coolant, meeting Ford specification WSS-M97B44-D.
Nice to know
70
Universal Coolant? Universal antifreeze is a traditional green, all-purpose inorganic, additive
formula suitable for use in passenger cars and light duty trucks Chrysler/Ford <2003 & GM <1995).
Arctic Blend Universal antifreeze/coolant contains a bittering agent to deter accidental swallowing.
ASTM D-3306 • ASTM D-4340 • ASTM D-4985 • ASTM D-4656 • ASTM D-6471 • Cummins 90T8-4 • Detroit Diesel 7SE298 • GM 1825 • GM 1899 • GM 6038M • GM 1825M • SAE 1941 • Thermo-King • TMC RP 302B • John Deere 8650-5
Nice to know
71
Universal Coolant Universal Gold premixed antifreeze/coolant is a
universal, hybrid organic acid technology (HOAT), extended life, low-silicate, phosphate-free antifreeze/coolant suitable for automotive/light duty and heavy duty diesel applications. This product was formulated to meet Ford WSS M97B51-A1 and Chrysler MS 9769 and other "global antifreeze" type specifications, as well as ASTM D3306, D4985 and D6210/11. Since this is a HOAT extended life antifreeze/ coolant it combines carboxylate organic acid salts with conventional inorganic salts and azoles; making it compatible with both extended life and conventional technology antifreeze/coolants.
Nice to know
72
Universal Coolant
Arctic Blend, Recycool, and Prestone Prime are coolants that have been formulated to be used in any vehicle. Two of these are ethylene glycol-based and one is propylene glycol-based. Exact specifications are available on the internet.
Nice to know
73
Passivation Passivate is a chemical reaction the takes
place between coolant additives and the metal that it protects. It is fairly fast, a few days, with some combinations and slow, weeks, with others. It creates the barrier between the metal and corrosion, and each chemical creates it's own barrier. Each chemical package (IAT, OAT, or HOAT) does its own passivation, and if you change chemical packages, passivation has to start over, possibly impeded by the earlier package.
It boils down to: DO NOT CHANGE PACKAGES.
Nice to know
74
Coolant Recovery and Storage
Some shops recycle used antifreeze
Should be stored until picked up for recycling
Notice double containers to help avoid spills
Need to know
75
Flushing a Dirty System
1. Drain system 2. Fill system with clean water & chemical 3. Run system to operating temp. (Heater on) 4. Drain system & fill with clean water 5. Repeat until drain water runs clear Any remaining flush agent will upset pH. 6. Fill system with 50/50 antifreeze/water mix 7. Run system to operating temp. (Heater on) 8. Adjust coolant level
Need to know
Caution: If flushing a really dirty system, be prepared to repair some leaks.
76
Flushing
Some communities permit draining into sewer. EG and PG will biodegrade. There is a problem however if coolant is spilled on open ground.
Need to know
77
Be sure to clean the overflow/surge tank
It should empty if you start draining with the cap in place.
Need to know
78
Mix Coolant 50/50 or use premix
?
79
Coolant Exchange Machine
Most shops use machines like this.
Coolant drains have become fragile and hard to find.
Need to know
80
Always check or replace the radiator pressure cap
The cap can be located on
1. the radiator
2. The coolant recovery reservoir
3. The upper radiator hose
Note the pressure.
Need to know
81
Cap has two seals
What will happen if the upper seal fails? What will happen if the lower seal fails?
Upper Seal
Filler Neck
Lower Seal
To CRR
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82
Never open when hot!
What can happen if the cap is removed from a hot system?
Need to know
1 psi will increase the coolant boiling point 2.7oF. A 15 lb. Cap will increase the BP 40.5oF.
83
Proper Fill
All of the air must be removed from the cooling system by one of these methods:
Bleeder screw: lets air escape Air Lift: evacuates system before fill Spill-Free Funnel: Lisle #22150 Fluid Exchange: requires special
equipmentNeed to know
84
Bleeder Valves
Use a clear hose attached to the bleeder valve and the other end in a “suitable” container
Prevents coolant from getting on the engine and gives the technician a visual clue as to color of coolant
Need to know
85
Leak Detection
A good system holds pressure
Tracer dye and some antifreezes glow under UV light
Need to know
86
What should Technician's do?
Check service information for the designated coolant and replacement interval
Check the coolant appearance and level at every service
Check the pressure cap appearance at every service
Check the appearance and pH for signs that the coolant should be replaced before the regular service interval
Check Freeze Point, pH, and Galvanic/Electrolysis
Need to know
87
Typical Questions/Answers
1. Are all green antifreezes the same?A. No-Chrysler used HOAT coolant that was green like IAT coolant
2. Can DEX-COOL be replaced with conventional green coolant?A. Yes, but then the coolant has be replaced every 24 months or 24,000 miles
88
Questions/Answers
3. Can coolants be mixed?A. No
4. Is DEX-COOL propylene glycol ?A. No. DEX-COOL and all other coolants are ethylene glycol except one labeled propylene glycol and is never used from the factory
89
Summary Not all coolants are the same Not all tap water is OK to use Premixed coolant usually produces
good results Check the coolant freezing/boiling point Check the coolant pH Always check or replace the pressure
cap, especially on DEX-COOL vehicles