Are you ready for A/C season?

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Repair shops – one question: Are you prepared for A/C season 2018? Circle the right answer: YES – NO

What do you mean you don’t have a pen? How can we perform diagnostics without a pen? Remember the pen is an instrument of the plan! Ok, here we go.

However, before you  begin, I have a few more questions. Have your pen now?

  • Have we performed our annual A/C machine health check on our existing R/R/R machines?
  • Have we checked our scales, replaced the filters and replaced the compressor oil?
  • Have we calibrated our units?
  • If you purchased a first time Recovery/Recycle/Recharge machine have you checked all your fittings, filters, and tank for leaks? If you did purchase a new piece of A/C gear, did you send in the EPA certification documentation? See this link
  • Have we checked and/or updated our Section 609 technician certifications?
  • Now the really hard one, have you updated your current scan tools?
  • I can go on, but you catch my draft (no, it’s not a typo, I meant draft not drift.
    Read the rest of this article now.

Download the entire issue of MACS ACTION magazine.


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It’s not your Daddy’s Section 609 certification anymore

By Steve Schaeber, MACS Manager of Service Training

If you were Section 609 certified before 2015 and you’re scrambling to find your card to buy refrigerant this Spring that’s fine, but after you calm down and get a shiny new copy of your old 609 card, think about this…the first R-1234yf cars are coming out of warranty and may find their way into your service shop.
R-1234yf and the motor vehicle air conditioning (MVAC) systems using it are different from CFC-12 and HFC-134a systems. Vehicles using this refrigerant require different service procedures and shop equipment. A technician will need the skills to recognize the differences between refrigerants and how to service or repair each system properly and safely.
This chemical is NOT a “drop-in” refrigerant or one that should be used in other systems. Systems designed for R-1234yf should only be charged with that refrigerant. Systems designed for other refrigerants should only use those correct products.
Are you R-1234yf service ready? Do you have the proper equipment and do you know the proper service procedures?
MACS has been explaining the differences between working on R-134a cars and R-1234yf cars for the last five years and we find as we answer calls and hold training clinics that there are still people who refer to themselves as service professionals who have not received any training on R-1234yf mobile A/C systems.

The current MACS Section 609 program contains comprehensive training information on R-1234yf systems including best service practices and SAE J-standards, as well as specific safety procedures to protect you, your shop and your customer’s car. This MACS technician training program conforms to and complies with the SAE International Standard J2845 “HFO-1234yf Technician Training for Service and Containment of Refrigerants Used in Mobile A/C Systems.”
Information is provided on tanks, labels and fittings identifying R-1234yf, finding leaks, using recovery, recycling and recharging equipment, servicing procedures and what you need to know about U.S. EPA SNAP rules. What’s a SNAP rule? SNAP is an acronym for Significant New Alternatives Policy Program and discusses acceptable refrigerants for use in mobile A/C systems. Check out
While it is true that you don’t have to take the Section 609 test again to fulfill current Section 609 requirements, if you are going to work on R-1234yf mobile A/C systems you owe it to yourself and your customers to have the best and most current information and training to make smart and efficient repairs.

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Look at this beauty!

Longtime MACS member Gus Swensen serviced this 1957 Bentley yesterday, he got their A/C back in shape at Cool Car Auto Air of Columbus, GA.

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Radiator Inspection

By Chris Tyson, MACS Heavy Duty Contributor

Our fleet includes more than 180 pieces of equipment, and while we implemented a periodic inspection program many years ago, there are still times when job requirements make it impractical or inefficient to bring certain machines back to the shop as scheduled. In these situations we try to send a technician to the various job sites to check things out. We also rely on operators to perform basic functions, such as checking the oil, air in the tires, and even making minor repairs when necessary.
But, there are times when some things fall through the cracks, and that’s exactly what happened with one of our Ingersoll-Rand DD14 Rollers. This machine usually travels from job to job, and as a result, it passes through many hands along the way. By the time it showed up at the shop, we found the engine coolant was significantly low, apparently due to a leaking radiator core. Further inspection indicated the radiator had become loose in its mount, which caused it to make direct contact with the blades of the cooling fan. As you can probably guess, the spinning fan damaged the fins, eventually making a few holes in the tubes, It was at that point, about halfway down the face of the radiator, that coolant was getting out.
We’re not sure how long the roller was operated while it was low on coolant. The operators we spoke with said they didn’t notice anything wrong with the machine, and since it was cold outside at the time, we had to take them at their word.
Making these repairs was pretty much straight forward, and we decided to send the radiator out to be recored rather than replace it with a new part. Anyone who’s dealt with cooling system components for machines like these knows that sometimes they can be quite pricey, and in this case it was cost prohibitive to go with new parts. Not a big deal though, it only took our local radiator shop just a few days to complete the job. Basically what they did was power wash and clean up the old parts, desolder the tanks and replace the damaged core with a new section. After pressure testing they repainted the entire unit. The DD14 radiator now looks as good as new.

While it’s rare anymore to send an automotive radiator out for repair, it’s actually quite commonly done with trucks and off-road equipment. Part of the reason why the replacement cost is so high is because the materials used are usually copper and brass, two expensive metals, which are worth quite a bit, even on the scrap market.
We were actually lucky in this situation that no major engine damage occurred, and the lesson we learned is that properly training your team can help alert you to, or even avoid, major problems from happening. Since then we added cooling system training to our operator and crew programs, so employees can learn more about the machines they work with each day. The hope is that the more familiar they become with their equipment, how it works, and what to look for, that they can raise those red flags before it is too late.

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Coolant chemistry review

By Dave Hobbs, MACS Technical Correspondent

Ethylene glycol (EG) was green back when I was a young tech, and its formula is fairly obsolete now. Its technical name is IAT (Inorganic Additive Technology), which contained Borates, Phosphates and Silicates. Silicates (think sand) can drop out of the coolant mix and become abrasive causing leaks and worn out water pump impellers. When air (from low levels) mixed in with the coolant (cavitation) and sharp bends in the cooling system were present, the velocity of the silicates in the coolant could at times cause the abrasive damage to happen in a very short time. Reports of new heater cores beginning to leak after a few hours of run time were not urban legends. The cavitation / abrasive effect acted like a sand blaster. When you changed the old green IAT regularly, there were very few problems. Although it had decent corrosion protection in the form of additives, they did wear out.

Organic Acid Technology (OAT) became common with DEX-COOL® which became the required coolant for GM and a few other manufacturers starting in 1996 as the 5-year / 150,000-mile coolant. Often called “Long Life” or “Extended Life” coolant, OAT gives a properly maintained vehicle a long service life mainly due to the increased longevity of the coolant’s additives. The OAT formula never became the panacea of OEM coolants. Chrysler, Ford, Mercedes and some others recommend not using OAT / DEX-COOL® coolant in their late model vehicles. HOAT (Hybrid Organic Acid Technology) a.k.a. G-05® is used by those OEMs. Studying the back of a Zerex bottle gives you the notion that a simple color coding system exists; green for the old Ethylene Glycol IAT, orange for OAT and yellow for the HOAT. While this may be true for some brands of coolants, it is not an official standard. Coolant makers can use whatever color dye they like. HOAT comes in blue, pink, orange and even green on some Chrysler products. While HOAT EG does contain some silicates, the amount is less than its predecessor (conventional green IAT OAT / GM DEX-COOL® had a very rough road in the first few years). OAT / DEX-COOL® contains ethylhexanoic acid (2-EH) as a corrosive inhibitor. 2-EH is prone to damage plastics like Nylon 66 used in intake manifold gaskets and radiators. G30 OAT and Peak Global OAT do NOT use 2-EH. Air was also determined to be a major factor in causing system breakdowns. If those formulas weren’t enough, Phosphated Organic Acid Technology (POAT) came into the market in 2008-on Mazda / Ford in a dark green color.
Which coolant do you use? OEM recommended? Universal? Personally, I go with the OEM unless there is a compelling reason not to. Budget limitations for select customers and vehicles would be a primary reason. If the customer hasn’t had any problems (yet) AND they’re on a very tight budget AND are willing to change that ‘universal’ coolant on a recommended interval AND they don’t plan to try to squeak out 250K miles, many of us trying to keep customers happy will do our best to appease them without going overboard or cheap.

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Another GM Antifreeze

By Paul Weissler, MACS Senior Technical Correspondent

Every engineering group of every car company wants exclusivity, and that often extends down to the smallest things. Then the corporate purchasing teams for the parts departments look them over and decide there are too many parts in the system that seem to be duplicative, thus they start eliminating them.
That’s why the car companies have multiple antifreezes at the start of new model families, and some time thereafter they’re down to a single antifreeze. GM has been using “DexCool,” a mixture of two organic acid inhibitors (2-ethylhexanoic acid and sebacic acid), plus a copper-brass inhibitor called TT (tolythriazole), formulated with an orange dye.
GM now has a new line of Chevrolet low cab forward medium and heavy-duty trucks and one of the engines is a 5.2-liter diesel four-cylinder. But it’s supplied by Isuzu which explains the specific antifreeze. Isuzu certifies its engines with a tested formula it describes as long life, meaning GM has to use that coolant until it can validate an alternative. That antifreeze is green as supplied, and GM warns not to use conventional American green, but instead a yellow dye coolant available from dealers.

That green antifreeze is not the same used in early 1990s Saturns either. That one was a low-silicate “extended life” antifreeze picked up from the Mercedes shelf, a rather curious selection because it contained nitrite, an addition they found helpful in protecting diesel engine cylinder wet liners.
So what is that antifreeze? We had it analyzed and it turns out that it’s just a single organic acid – 2-EHA plus TT. That differs from DexCool, which has the second organic acid (sebacic acid), and various other antifreezes that use other ingredients, such as molybdate, along with TT. You can get that specific antifreeze at dealers, although our view is you can use DexCool, as it has certainly proved to be compatible with 2-EHA and TT. These new medium and heavy-duty trucks are primarily for “upfitters,” who attach specific design bodies to them, such as for construction and garbage removal.
Green antifreeze is used only with the 5.2-L diesel, which GM made clear is essential. First, there is a green propylene glycol antifreeze, which may cause engine damage. Second, Isuzu provides the diesel engine warranty for GM, and (as happens with many outside suppliers) mandates a specific coolant. Also noteworthy is the fuel-to-air fuel system cooler, which is mounted in front of the rear axle. The diesel fuel cooler is intended to compensate for higher fuel pressure and temperature (caused by changes in camshaft timing). The cooler is part of the fuel return circuit and it reduces temperature of the fuel before it goes back into the fuel tank.
Those new low cab forward chassis are Class 3 to 5 (3500, 3500 HD, 4500, 4500 HD, 4500 XD, 5500 HD and 5500 XD). The engine lineup also includes a 6.0-liter gasoline V8, a 6.0 CNG/LPG-capable version, and a second Isuzu four-cylinder diesel, with a displacement of 3.0 liters, which also gets that green antifreeze as the OE fill.

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The time for mandatory Section 609 recertification is now

The new refrigerant purchasing rules that took effect January 1, 2018 have had service shops, distributors and the MACS office in an uproar. At the MACS office, the faxes, emails, phone calls and mail deliveries never stop. Every technician wants to make sure they can buy refrigerant, but it makes me wonder: Do they know what to do with it once they get it? Are they handling it safely, properly and responsibly?

Many of the questions posed to the MACS staff about the Section 609 rules and test requirements from working technicians have been staggering for their lack of information awareness.

Since January 1, 2018 the MACS office has processed over 40,000 Section 609 certifications, the majority I am pleased to say are new Section 609 certifications of technicians actually taking the test which was updated in 2015 to include R-1234yf service and repair information. If you are ever going to service an R-1234yf system, this information is vital for repair procedures and for shop and personal safety. For $20, it is some of the most comprehensive training a technician can get on servicing mobile A/C systems with R-1234yf.

In 2010, MACS asked the U.S. EPA to require mandatory recertification of all technicians to include training in the service and repair of R-1234yf systems. In our letter we said, “…We contend that it is extremely important for the Agency to require specific training prior to the use of the new refrigerant by service technicians. We believe that voluntary training will leave an unknown (and very likely large) segment of the service community untrained and at risk.”

MACS also said, “The process of requiring individuals holding a particular certification to periodically recertify is common in the industry and referenced in the standards established by the National Commission for Certifying Agencies (NCCA). The general purpose is to help ensure that certified individuals maintain competence over a defined time period. In the case of the certifying agency most respected in the automotive arena, ASE (National Institute of Automotive Service Excellence), that period is five years and is based on the estimated rate of technological change within the automotive industry.”
Training is available to all automotive technicians. As professionals, we should take advantage of as much career training as we can. However, because so many will not voluntarily be trained, EPA should require Section 609 recertification.


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Tariffs: A two-edged sword

By Keith Leonard, Esquire.

While not for the first (or the last) time in United States history, the current administration has announced the imposition of tariffs on imported steel and aluminum (though not as to steel and aluminum imported from certain countries until May 1st). The imposition of the tariffs has been couched as being done in the interest of protecting national security, but tariffs are really also a form of trade protectionism. National security protection was chosen, because it is one of the exceptions to the trade rules of the World Trade Organization (the WTO). In retaliation for the United States putting such trade barriers in place on items produced by China, that country has released its own set of tariffs on goods being exported to China from the United States.
The United States International Trade Commission (USITC) is the organization responsible for publishing the Harmonized Tariff Schedule of the United States Annotated (HTSA); this Schedule provides the applicable tariff rates and statistical categories for all merchandise imported into the United States. The Schedule is based on the international Harmonized System, which is the global system used to describe most world trade in goods.

It is certainly too early to tell what effects the imposition of such tariffs will have on either the economy of the United States or the global economy. Caution and concern over these tariffs have been expressed by both liberal and conservative analysts. In hindsight, one of the most criticized sets of tariffs in this country’s history was imposed pursuant to the Smoot-Hawley Tariff Act of 1930, during the Great Depression.

Adopted with the goal of protecting American industry and agriculture from foreign competition, the tariffs are recognized as having actually prolonged the economic downturn of that era. In response to those tariffs, many trading partners of the United States reacted (as has China now) by raising their own tariffs, with a reduction in world trade. As well-meaning as trade protectionism may seem (and sound), we live in a time of a global economy where free trade has been the common strategy of most international countries since World War II. A national interdependence has been enjoyed among these countries. Once raised, it is also commonly very difficult to reduce tariff levels; the protected parties never want to see the duty reduced or removed.

The manufacturing sector of the motor-vehicle industry is the second largest employer among all manufacturing industries in the United States and auto parts and tires contribute the most direct jobs to the motor-vehicle sector. However, the United States auto parts industry has not turned around economically as fast or as well (in terms of jobs) as the automakers have in this country from the recession of 2008.

One so-called think tank (the Economic Policy Institute, with a commonly accepted liberal bias to its reports) published an article in January 2012 citing multiple statistics in support of its conclusion that jobs in the auto parts industry in the United States were at risk due to subsidized and unfairly traded Chinese auto parts. The Economic Policy Institute’s response to President Trump’s March 1st announcement of tariffs on steel and aluminum should therefore come as no surprise – the President’s “announcement should mark the beginning, rather than the end, of efforts to develop coordinated global responses to the problems of excess capacity in steel and aluminum trade.”

On the other hand, a conservative think tank, the Heritage Foundation, published an article in advance of the tariff announcement entitled “The Trouble with Tariffs”. The author pointed out that the anticipated result this year of the administration’s prior imposition of tariffs and quotas on imports of solar cells and modules is fewer American jobs, higher prices for American consumers, and retaliation from America’s trading partners; certainly not protecting American businesses. The author concludes that “Nobody wins a trade war.”

Since many of the parts and components that the OEMs purchase are made from domestic- and foreign-sourced steel and aluminum parts, a substantial ripple effect on the entire automotive sector is expected. As it is the importer of record who is responsible for paying all duties, any contractual arrangements with suppliers should be reviewed to determine how that risk has been allocated between the parties. The effect on domestic steel prices is also uncertain, as is the “winner”, if any, of this potential trade war.

Remember that laws are constantly changing and are often not uniform throughout the United States. Do not place unqualified reliance on the information in this article. Always contact legal counsel for detailed advice.
If you have a particular issue, law or problem you would like to see addressed in a future column, please contact me at

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The mobile A/C industry on display

The MACS trade show has always been something special among automotive service exhibitions.  It’s a place where you see parts, tools and equipment for mobile climate control and vehicle cooling systems that you won’t see elsewhere.  And you usually first see them at the MACS show front and center – not hidden behind crankshaft grinders or other things from the wide wide world of motor vehicle maintenance, diagnosis and repair.

The more compact nature of the MACS show also enables you to see everything in a single day. Although you’ll probably linger at many of the displays to get the kind of information you can’t absorb at the “really big” shows – even from the same manufacturers.

Our first simple examples: recovery/recycling/recharge equipment. The MACS trade show featured engineers from the equipment manufacturers who participated in the SAE Interior Climate Control Committee meeting the day before.  So if you want to ask about details related to company products, you’ll find experts with answers. Not just salesmen are at the MACS show. Read this entire article.  View the whole magazine.

Visit the MACS website


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Seeking yf

By Steve Schaeber, MACS Manager of Service Training

MACS has been tracking refrigerant use by vehicle manufacturers for quite some time and, as expected for the 2018 model year, we have seen a few more manufacturers choose to change over a few or even all of their US offerings to use the new refrigerant HFO-1234yf.

January 26 was Media Day at the 2018 Philadelphia Auto Show, and MACS was there to check out 28 brands, open 239 hoods, and discover what the OEMs are doing with their A/C systems. We were not surprised to see more vehicles using the new refrigerant, but we really didn’t expect to learn that a few decided to change over all of them in just one model year! In the end, we calculated that similar to last year, about 48 percent of the new models are using yf.

Several car makers that previously had zero vehicles with R-1234yf for 2017 have now joined the ranks, with the biggest surprises coming from BMW and Mini. Each of the 11 BMW models we inspected were charged with the gas, along with the seven Mini Cooper variants. We expected a few, but certainly not all of them! In fact, BMW, Jaguar, Land Rover and Mini were the only car lines that didn’t use R-134a in anything (JLR changed over all of their product lines for the 2016 model year).

Still, there are a shrinking number who continue to use R-134a exclusively, including Acura, Infinity, Mazda, Nissan and Volvo. We didn’t expect to see yf in any of the new Nissans or Infinities, but were surprised that Acura didn’t even have one, considering that seven of the nine Hondas have already been changed over. Mazda showed six models with 134a (Mazda 3, 6, CX-3, CX-5, CX-9 and MX-5 Miata), while none of the six Volvos (S60, S90, T8, V90 and XC60) use yf.

VW made a big jump compared to last year when they only had the Atlas prototype. Now it is using R-1234yf in the production model Atlas along with Beetle, Golf, Passat and Tiguan. Note that Tiguans built in Mexico are using yf, while the Tiguan Limited imported from Germany still uses R-134a. VW’s cousin Audi is going a little slower, using the refrigerant in both a passenger car (the A4) and a crossover SUV (the Q5) before making a larger commitment. A smart move that some other OEs have also made.

Most of the GMs have already switched, including all of the Cadillacs as reported last year. GMC has the most at 83 percent followed by Chevy at 65 percent and Buick at 50 percent. FCA continues to lead the pack, with all but one model using yf (the 2018 Fiat 124 Spider Abarth).

Others, which we’ll continue to keep an eye on as the year progresses, have come in either at or below 50 percent. After all, the 2019 model year is only a few short months away, and Ram has already introduced its 2019 Ram 1500 pickup to much fanfare, as evidenced by the well-attended media event the manufacturer held in Philadelphia.

 This chart compares the percentage of models being filled with either R-134a or R-1234yf refrigerant, listed by manufacturer. (Credit: Steve Schaeber)

OEM Total # of Models R-134a % R-1234yf %
Acura 5 100.00% 0.00%
Audi 9 77.70% 22.20%
BMW 11 0.00% 100.00%
Buick 8 50.00% 50.00%
Chevrolet 17 35.29% 64.70%
FCA 8 12.50% 87.50%
Ford 14 57.14% 42.89%
Genesis 3 33.33% 66.66%
GMC 6 16.66% 83.33%
Honda 9 22.22% 77.77%
Hyundai 8 75.00% 25.00%
Infinity 6 100.00% 0.00%
JLR 7 0.00% 100.00%
Kia 10 30.00% 70.00%
Lexus 9 88.88% 11.11%
Lincoln 5 60.00% 40.00%
Mazda 6 100.00% 0.00%
Mini 2 0.00% 100.00%
Mitsubishi 4 50.00% 50.00%
Nissan 12 100.00% 0.00%
Ram 2 50.00% 50.00%
Subaru 7 71.42% 28.57%
Toyota 14 71.42% 28.57%
Volvo 6 100.00% 0.00%
VW 7 28.57% 71.42%


Posted in #1234yf, ACtion Magazine, Automotive training, MACS Member, Mobile Air Conditioning, Refrigerants, Training | Tagged , , , , , , | Leave a comment