Embed Size (px)
Citation preview
1Tom Birch, 3/07 1
Coolants
Tom BirchJim Halderman
2
Introductions: Tom Birch
• Retired instructor from Yuba College, Marysville, CA.
• Author of many automotive textbooks
• Former officer in CAT and NACAT Board Member
3
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
4
Topics to be Discussed
Engine coolants- Purpose and function Water (1/2 of the coolant)Coolant TypesCooling system testingCooling system service
55
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
66
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
77
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
88
Good Quality Water
Good quality water types include:
Distilled- boiling water and then cooling the steam back to water
• Deionized (Also called demineralization or purified)-Has the minerals removed such as sodium, calcium, iron, copper, chloride, and bromide
Need to know
9
City Tap Water
Usually unknown quality Can have unwanted
chlorides, minerals, or salts Unknown pH
Need to know
10
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
1111
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.
Nice to know
1212
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)
Need to know
13
Ethylene Glycol
Ethylene glycol is the base antifreeze used in every OEM factory fill. The additive package will vary.
Need to know
14
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
1515
Poison
Need to know
16
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
Bittered States
At this time, 7/2010, 12 states require antifreeze with a bittering agent: dentonium benzoate. They are:
3 states: Illinois, Massachusetts, New Hampshire, and Ohio are working on a similar rule.
1818
Additives
The major additives:
1. reduce corrosion
2. buffer pH
3. add color (dye)
Need to know
19Need to
know 19
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.
2020
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.
2121
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
22
OAT-continued
NAPS=nitrates, amines, phosphate and silicate free
Nice to know
23
OAT=DEX-COOL is one brand
Nice to know
24
DEX-COOL Concerns
Root cause= air entering system
Check cap replace cap
Air causes ‘Brown Gunk’
Rust then causes blockages
Need to know
Brown Gunk
Tom Birch, 3/07 25
DEX-COOL + Air = Brown gunk
Low coolant level exposes iron to rust, and filling that system dissolves the rust into the coolant.
26
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
Need to know
27
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
2828
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
29
HOAT=Red; Pink; Yellow or Blue
Nice to know
POAT Coolant Phosphated Organic Acid
Technology (POAT) Dark Green in color Used in Mazda-based Fords (2008+) WSS-M97B55-A (same as Mazda FL-
22) $34.95 per gallon
Ford Motor Company & E-OAT
Tom Birch, 3/07 31
The E = European, low silicate and phosphate free; Ford of Europe has validated DexCol and uses it with no problems. Ford of U.S. has reengineered all of their new engines (No- Cavitation water pumps and no-silicone rubber or Nylon 66) to work with this formula.
Ford/Mercury Coolant
Tom Birch, 3/07 32
The 1999—2001 Cougar used a OAT DexCool clone, but had issues with water pump cavitation.
Pre 1999 99—01 2002 2003 2004
DexCool & OAT that meets GM Spec.
Tom Birch, 3/07 33
Prestone markets an OAT antifreeze (Extended Life: “compatible with ANY antifreeze/ coolant”) that meets the GM DexCool spec.; it is less expensive than DexCool-labeled products because of no-royalty cost.
Slow Passivation
Tom Birch, 3/07 34
It takes about 5,000 for an OAT to establish protection. Some manufacturers use purified water in the 50-50 factory fill. This helps keep the cooling system very clean until the protection is there.
35
Passivation
Passivation= is a chemical reaction the takes place between coolant additives and the metal that it protects
Takes a few days or few weeks It creates barrier between the metal and
corrosion Each chemical package does its own passivation if you change chemical packages, passivation has
to start over It boils down to: DO NOT CHANGE PACKAGES.
Nice to know
36
“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
37
“G” Designations-continued
G11=Blue VW used before 1997 G12=Pink/Red VW 1997+ G12=Purple VW 2003+ HOAT formulation; phosphate free
?
38
“G” Designations-continued
G48=Low Silicate and Phosphate free
Blue Color NAP =nitrates, amines, phosphate
free BMW
?
39
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
4040
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
41
Antifreeze Applications n
4242
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
Nice to know
4343
pH Effects
Fresh antifreeze pH= 9 and 11
Used coolant pH= 7.5 and 10
It can also increase electrolysis
( the dissimilar metals in contact with an electrolyte can produce a simple battery)
Need to know
44
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
45
Desired pH
Need to know
4646
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
Nice to know
4747
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
48
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
4949
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
50
Corroded Water Pump
One of the reasons for the removal of silicates from coolant
Need to know
51
Corroded pump can cause:
reduced coolant flow and an overheating condition
Need to know
5252
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
53
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
54
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
5555
Corrosion
Corrosion is the “decomposition of metal”
(called rust or aluminum oxide, the whitish material that forms on aluminum components)
Oxide formation:
1. eats away at the parent material from the outside
2. forms an insulating barrier for heat transfer
Need to know
5656
Corrosion
aluminum oxide, often found on coolant outlet/stat cover
Need to know
57
Metal Corrosion
This iron tube has been ruined by rust.
Need to know
58
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
59
Metals
Nice to know
60
Bi-Metal Corrosion
Ions move from more active metals to less active metal through the coolant which acts like the electrolyteNice to know
6161
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
62
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
63
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
Need to know
64
Depletion Rate of Additives
Need to know
65
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.
Need to know
66
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
Need to know
67
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
Need to know
6868
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.
Need to know
69
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.
Need to know
70
Freeze Protection, Hydrometer
? Accuracy
Need to know
71
Can you trust this?
Need to know
72
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
73
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
74
pH Tests
pH can be measure using test strips or a meter.
Fairly accurate and costs pennies/test.
Need to know
75
pH Meter
This Milwaukee is probably more accurate and cost $30.00.
Need to know
76
Coolant Replacement
1. 15 to 20% remains in the system after it has been drained
2. Fill system with antifreeze first and top off with water
3. Be sure to use the specified coolant
(GM warns not to reuse coolant drained from the system)
(Mercedes has a lifetime coolant, drain, filter, & reuse)
Need to know
77
Coolant Replacement-#2
Check the pressure cap and radiator for faults Check all hoses and always use coolant hose
Need to know
78
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
79
Universal Coolant Universal Gold =HOAT, extended
life, low-silicate, phosphate-free antifreeze/coolant.
This product meets Ford WSS M97B51-A1 and Chrysler MS 9769 and other "global antifreeze" type specifications, as well as ASTM D3306, D4985 and D6210/11
Nice to know
80
Universal Coolant
• Arctic Blend
• Recycool
•Prestone Prime
coolants that have been formulated to be used in any vehicle
Nice to know
81
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
82
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.
83
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
84
Be sure to clean the overflow/surge tank
It should empty if you start draining with the cap in place.
Need to know
85
Mix Coolant 50/50 or use premix
?
86
Coolant Exchange Machine
Most shops use machines like this.
Coolant drains have become fragile and hard to find.
Need to know
87
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
88
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
Need to know
89
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.
90
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
91
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
92
Leak Detection
A good system holds pressure
Tracer dye and some antifreezes glow under UV light
Need to know
93
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
94
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
95
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
96
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
97
Resource materials
