Reported Dec 2, 198120,156 vehicles affectedALLISONBuilt Dec 1, 1979 – Dec 1, 1980
The defect
If excess combustible fluids such as diesel fuel or lubrication oil build up in these engines, the excess fluid can be carried into the intake system through a valve.
The remedy
The crankcase depression regulator valve will be replaced with a road draft tube. This repair IS to be done at the same time as the repair for campaign 80C-4.
Vehicle category: medium trucks and school buses with 8.2 liter diesel engines.system: engine and engine cooling; crankcase ventilation system.consequences of defect: if this condition occurs, engine speed may increase,independent of throttle control. This could result in loss of vehicle control,without prior warning, and an accident.note: owner IS advised not to overfill the crankcase while changing or addinglubrication oil. Should loss of throttle control be experienced during vehicleoperation, the transmission should be shifted to neutral, the vehicle braked toa stop, and the ignition key turned off. No attempt should be made to restartthe engine.