LEAK AT/NOISY COOL. PUMP (COOL PUMP/TIMING BELT/IDLER PULLEY)

SUBJECT: LEAK AT/NOISY COOLANT PUMP (REPLACE COOLANT PUMP/INSPECT TIMING BELT AND IDLER PULLEY)

MODELS AFFECTED: 1992-93 SUNBIRD MODELS W/2.OL ENG (RPO LE4) ENGINE VIN: H

CONDITION:

--------- Coolant leaks from the coolant pump and/or there is a grinding noise coming from the coolant pump. There also may be a knocking noise from the timing belt tensioner shifting back and forth.

CAUSE:

----- A second weep hole was eliminated from some coolant pumps. Coolant may leak past the internal seal into the bearing of these pumps causing premature bearing failure.

CORRECTION:

---------- Replace the coolant pump if it leaks coolant, is noisy, or if the shaft is tight or difficult to turn.

A. If replacing coolant pump with a part from dealer inventory, ONLY USE THE PUMP IF IT HAS TWO (2) WEEP HOLES. (Refer to Figure 1.)

Coolant pumps with one (1) weep hole should be returned to GMSPO. Please use GMSPO form PC 659. Indicate "SPECIAL RETURN".

B. If replacing coolant pump with the new part (GM P/N 93215645), it will have two (2) weep holes.

Inspect the timing belt and cover and replace it as necessary if there are cracks or visible damage.

Inspect the timing belt tensioner for damage and replace it if the arm is cracked or broken (refer to Figure 2).

SERVICE INFORMATION:

1. Identify that the coolant pump is leaking or that it is the source of the noise.

2. Remove the coolant pump (refer to Section 6B of the 1992 or 1993 Sunbird Service Manual for removal procedure).

3. Inspect the timing belt tensioner for cracked or broken tensioner arm. (Refer to Figure 2.) Replace timing belt tensioner if arm is cracked or broken.

4. Install the new coolant pump (refer to Section 6B of the 1992 or 1993 Sunbird Service Manual for installation procedure). Be sure the new coolant pump has two weep holes.

VEHICLE BREAKPOINT INFORMATION:

The following breakpoints identify the vehicles that may be affected with this condition:

Beginning Through and Year Model Name Transaxle Assembly Plant VIN Including ---- ---------- ------------------------ --------- ----------- 1992 Pontiac Sunbird Auto/Man Lordstown, OH N7539565 End of Prod 1992 Pontiac Sunbird Auto/Man Ramos Arizpe, Mex NS821299 End of Prod 1993 Pontiac Sunbird Auto/Man Lordstown, OH SOP P7523040 1993 Pontiac Sunbird Auto Ramos Arizpe, Mex SOP PS810794 1993 Pontiac Sunbird Manual Ramos Arizpe, Mex SOP PS810845

PARTS INFORMATION:

Part Number Part Description ----------- ---------------- 93215645 Kit, Coolant Pump (New part number with two (2) weep holes)

Parts are currently available from GMSPO.

Refer to Parts Catalog Tensioner, Timing Belt (Replace as necessary)

Refer to Parts Catalog Belt, Timing (Replace as necessary)

Refer to Parts Catalog Cover, Timing Belt (Replace as necessary)

WARRANTY INFORMATION:

Labor Time Operation Number: J3480

Labor Time Allowance: 2.2 Hours ADD A: with A/C 0.1 Hour

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.