Defective Engine Component in Blue Bird School Buses Leads to NHTSA Inquiry

Defective Engine Component in Blue Bird School Buses Leads to NHTSA Inquiry
Image: Pexels
March 26, 2015

An estimated 204,441 school buses and related vehicles are the subject of a new investigation being conducted by the National Highway Traffic Safety Administration (NHTSA).

In a letter dated June 11, 2014, Blue Bird Body Company notified NHTSA of its internal finding that a defect exists in certain model year 2008-2013 All American rear engine school buses manufactured between April 3, 2007 and December 15, 2012.

The engines installed on the affected buses were manufactured by Cummins, Inc. Blue Bird says that during high engine RPM, the thermostat installed in the Cummins ISC07, ISC10 and ISL-G engines may cause a pulsation in the coolant flow. Over time, the company says that this pulsation could weaken the passenger compartment heater hose inner lining. As a result, the heater hose may rupture which could lead to hot coolant entering the passenger compartment, which poses an injury risk to passengers.

The affected Blue Bird school buses were all recalled and assigned recall number 14V-313 by NHTSA's Office of Defects Investigation (ODI).

This issue also affects model year 2008-2013 Blue Bird All American rear engine non-school buses manufactured between May 9, 2007 and November 12, 2012. These buses were also recalled and assigned recall number 14V-314 by ODI.

In addition to Blue Bird, Cummins provided NHTSA with a purchaser list identifying the other manufacturers that may have incorporated these defective engines into their vehicles.

NHTSA says that the purpose of this Equipment Query (EQ) investigation is to contact the other companies that purchased the Cummins SC07, ISC10 and ISL-G engines, notify those companies of Blue Bird's defect decisions, and request similar defect decisions be made on their vehicle products.

The company's will also have the option to inform ODI's Recall Management Division (RMD) as to why a safety defect decision is not appropriate on their vehicles.