ACtion Magazine - September/October 2016 - 14

Engine coolant hose failure By Tom Trojan, Gates Senior Fluid Products Manager E ngine coolant hose is one of the most overlooked components in a vehicle today. Coolant hose no longer includes just an upper, lower and heater hose as coolant now runs to the fuel system, turbocharger, auxiliary heaters, hybrid components, etc. Certain vehicles can have 30 or more coolant hoses, some of which are difficult to visually find, but all destined to fail. According to a recent market analysis, more than half of coolant hoses are replaced not because of preventative maintenance but because they failed. These failures lead to anything from a stranded driver to a significant and costly engine overhaul. It wasn't that long ago when hoses were replaced every 4 years, so why are they ignored to such an extent today? Cooling system performance has improved substantially over the years through increased capability, superior heat control, bet- 14 ACTION * September/October 2016 ter materials and computer technology. Today's hose construction has also drastically changed because of premium EPDM (ethylene propylene diene monomer) rubber material. What was once a simple inspection and "squeeze" test to check for a failing hose is now a challenging assessment, even with the hose off the vehicle. The number one cause of hose failure is electrochemical degradation, or ECD. ECD is caused by an electrical charge carried through the coolant from component to component. It occurs because the hose, liquid coolant and the engine/ radiator fittings form a galvanic cell or "battery." This chemical reaction causes micro-cracks in the hose tube, allowing the coolant to attack and weaken the hose reinforcement. Failures result from internal striations or cracks in the hose rubber, leading to a pinhole leak or a burst hose. One way to check a coolant hose

Table of Contents for the Digital Edition of ACtion Magazine - September/October 2016

ACtion Magazine - September/October 2016
Outlook — Andrew Fiffick
Service Port — Steve Schaeber
Leonard’s Law — Keith Leonard, Esq.
Cooling Corner
Virtual View — Angie Kilbourne
What you should know about A/C hose compatibility with R-1234yf
By The Numbers
Member Profile
CO2 air conditioning development comes alive in Germany
Industry News
Association News
New Products and Services
Last Watch — Elvis Hoffpauir

ACtion Magazine - September/October 2016