Motor Coach Manufacturer Recalls Vehicles for Possible Window Bonding Issue
August 25, 2010

Motor Coach Industries Inc. (MCI) has issued a recall for several of its motor coaches equipped with SE-GI passenger windows. The adhesive bond between the glass in the windows and the aluminum window frame on the affected vehicles may degrade over time and the windows may become partially or completely detached from the vehicle’s frame, according to a report from the National Highway Traffic and Safety Administration (NHTSA).

Approximately 1,087 vehicles could be affected by the recall, from MCI’s E4500 (2001-2004), E4500C (2002-2006), J4500 (2001-2005) and J4500C (2006) lines. The window assemblies were supplied by SE-GI in Norco, Calif. The recalled windows represent approximately 29 percent of the company’s total E and J coach lines during the affected model years, according to documentation MCI provided to NHTSA.

MCI says that SE-GI “implemented process improvements in its window assemblies” at the end of 2006, and all vehicles included in the recall are equipped with window assemblies made prior to this time.

The impacted SE-GI passenger windows were designed to appear frameless, according to MCI, and the assemblies are made from an interior lite of laminated glass and an exterior tempered lite; the two lites of glass are separated by a seal around their perimeter, and the entire aluminum window frame is mounted to the coach frame by either mechanical fastening or using both mechanical fastening and polyurethane adhesives, according to the report. However, company officials suspect the bonding issue is caused “by failure of the paint coating on the surface of the aluminum window frame to properly adhere to the surface of the aluminum.”

“The supplier, SE-GI Products Inc., has informed MCI that the cause of the failure may be insufficient paint curing and/or possible chemical reaction between the paint and the adhesive,” writes the motor coach manufacturer.

MCI first received a report of an issue in March 2009, when a customer advised the company that one of its sidewall windows had detached from a bus while in transit; the company notified SE-GI and “requested a root cause and corrective action analysis.” A second customer reported a detached window in July 2009.

MCI also began investigating, according to its report, and found debonding in approximately 15 percent of the vehicles inspected. Though MCI officials say SE-GI has advised of the possible insufficient paint curing and/or chemical reaction cause, the company “has not provided a permanent corrective action.” However, the motor coach manufacturer has developed a retrofit kit to adhere the debonded window assemblies.

“The retrofit repairs consisted of removing the old inner seal and bonding the inner window laminated glass directly to the coach frame,” writes MCI. The design for the retrofit repair was completed in July 2010.

The company says it will inspect, test and repair all affected customers’ vehicles. Notifications to customers were scheduled to go out pending approval of the August 18 draft of its letter to customers by NHTSA.

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