Mobile Air Conditioning Society Cooling System Panel Warns about Coolant Mixing, Corrosion

The Mobile Air Conditioning Society (MACS) Worldwide held its 23rd annual convention and trade show, Reality Check 2003 at the Marriott New Orleans, January 30-February 1, 2003. One of the highlights of the convention program was MACS’ first ever coolant symposium held on Saturday, February 1. The results of the symposium indicate that consumers may be neglecting proper maintenance of their engine cooling systems resulting in the same kinds of system problems as result from not checking their engine oil and tire pressure.

Many questions concerning the use of coolant and the misinformation surrounding coolant system management were posed and the panel of industry experts from the OEM and aftermarket segments reached consensus on several topics including:

Total coolant/cooling system management is an issue that should be of concern to both consumers and service technicians.

Coolant system maintenance and change intervals are not being adhered to resulting in major problems for today’s automotive engine cooling systems.

Chemical stability of the engine coolant is extremely important to prevent its breakdown.

Engine cooling systems that contain air, from either the lack of /improper bleeding procedures/ not maintaining proper fill levels; incorrect coolant mixture; core sand and other loose material being circulated in the coolant can lead to a leaking heater core. These types of problems are generally the result of erosion and/or corrosion and are often mistakenly thought to be caused by electrolysis. While electrolysis can be the cause of heater core failures, actual cases are rare, contrary to recent popular conjecture. Improper grounding of aftermarket electrical equipment, such as sound systems, may result in cooling system component failures due to electrolysis.

Distilled water should be used. A refractometer is the best tool to use for in-shop coolant testing.

Most OEM vehicle manufacturers do not approve of the use of recycled coolant in their vehicles. Currently, there are no existing machines or processes certified to meet the ASTM purity requirements for on-site recycled engine coolants for use in typical auto repair shops.

“Coolant system management should be a regular part of every engine cooling system service procedure and maintenance activity,” remarked Ward Atkinson, MACS Technical Consultant. “We began the discussion on proper coolant management in this panel discussion and we hope to keep the dialogue going in the industry to promote proper Total Coolant System management procedures in every professional repair shop.”