CRACKED CYLINDER HEAD INFORMATION

VEHICLES AFFECTED: 1982-84 'J' Series And 'S, T' Trucks Equipped With 1.8L (L46 And LJ9) And 2.0L LQ5, LQ2 And LR9) L4 Engine

Some 'J' series and 'S/T' truck engines may develop coolant loss which may be due to a cracked cylinder head. The crack develops across the No. 6 intake valve spring seat area and continues across and behind the No. 4 and No. 5 exhaust valve spring seat. With the aid of dye check, the crack is visible to the unaided eye (see illustration).

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.