GM Service Manual Online
For 1990-2009 cars only

REVISED CYLINDER HEAD BOLT TORQUING PROCEDURE

MODELS/YEARS 1989-1990 NINETY-EIGHT, EIGHTY-EIGHT AND TORONADO EQUIPPED WITH A 3800 (VIN C) ENGINE

IMPORTANT: This bulletin revises the cylinder head bolt torquing procedure for the 3800 (VIN C) engine that appear in 1989 and 1990 Service Manuals. The procedure for the 3800 (VIN C) is the same as that for the 3300 (VIN N). The bolt torquing sequence remains the same for both engines.

Please mark a reference to this bulletin in the following service manuals:

- 1989 Eighty-Eight and Ninety-Eight, page 6A5A-12 - 1989 Toronado, page 6A5E-11 - 1990 Eighty-Eight and Ninety-Eight, page 6A8-12 - 1990 Toronado Preliminary, page 6A8-12

INSTALL OR CONNECT

1. Clean threads in the block using a 7/16-14 tap.

2. Clean bolt threads using a wire brush.

3. Cylinder head gasket on block.

4. Apply sealant, part number 1052080 on bolt threads.

5. Cylinder head bolts.

6. Tighten cylinder head bolts to 47 N.m (35 lbs.ft.) in sequence.

7. Rotate each bolt 130 degrees in sequence using J36660 torque angle meter.

8. Rotate the center four bolts an additional 30 degrees in sequence using J36660 torque angle meter.

9. Pushrods, guide plate and rocker arm assemblies.

Apply Threadlock, GM part number 12345493, to rocker arm pedestal bolts before assembly. Tighten rocker arm pedestal bolts to 38 N.m (28 lbs. ft.).

10. Intake manifold

11. Valve cover

12. Exhaust manifold

Front (left) cylinder head.

- A/C compressor bracket bolt to 70 N.m (52 lbs. ft.). - Generator support bracket to cylinder head. - Generator. - C31 and spark plug wires.

Rear (right) cylinder head.

- Belt tensioner assembly. - Power steering pump. - Fuel line heat shield.

13. Negative battery cable.

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.