NOISY A.I.R. PUMP LOOSE A.I.R. PUMP PULLEY BOLTS

VEHICLES AFFECTED: All 1984 C,K,G, Trucks Equipped With Gasoline Engines

Some 1984 vehicles have experienced a noisy A.I.R. pump, which may be caused by loose A.I.R. pump pulley attaching bolts. This condition may be corrected by the installation of a new A.I.R. pump, A.I.R. pump pulley, or both as required if damaged, and new bolts and bolt spacers. The new bolts with the spacers must be torqued twice to insure proper clamp loads on the pulley. A.I.R. pumps used on passenger cars with the same engine applications should not be substituted on trucks because they do not contain the heavy duty vane assembly designed for truck usage.

PARTS REQUIRED PART NUMBER -------------- ------------ A.I.R. Pump

MODELS

C,K 1,2 (250D, 305H, 350P, 350L) 7842812 G 1,2,3 (250D) 7842812 C,K 2,3 (292T. 350M, 350E) 7843606 C,K 2,3 (454W) 7843607 G 1,2,3 (305H, 305F, 350E, 350L, 350M) 7843607

A.I.R. Pulleys

MODELS ------ C,K 1,2 (250, 292) W A/C 14087012 C,K 1,2,3 (250, 292, 305, 350, 454) 14081703 (Stamped BDC) G 1,2,3 (250, 305, 350) 14037738 (Stamped BA) C,K 1,2,3 (305, 350) 14037738 (Stamped BA) G 1,2,3 (305, 350) Non A/C 14024171 (Stamped AF) 130mm Dia. Bolts 14077183 (10.9 x 17mm) Quantity 3 Spacers 120392 (3.15mm Thick) Quantity 3

INSTALLATION

Remove damaged pump and pulley. Remove necessary fittings or valves attached to the pump.

Install fittings or valves on new pump using necessary gaskets or seals for proper attachment to the pump.

Install the new pulley on the pump using the spacers on the bolts (see illustration). On G-Van models, the pulley must be installed after the pump is installed into the truck due to the large diameter pulley used on 305-350 non A/C application.

Note: Pulley bolt spacers (P/N 120392) must be used or damage to the new pump and pulley may occur.

Tighten the three attaching bolts to 12-15 N.m. Retorque all three bolts to 15-16 N.m using a click type torque wrench or other suitable torque wrench.

Note: The secondary torque procedure must be completed immediately following the initial torque due to the presence Of ddhesive locking material on the bolt threads.

Install A.I.R. Pump belt and tighten to specifications using belt tension gauge J23600 or BT 33-73F.

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.