Usage:
3208 Marine Engines (1Z4296-Up, 75V8546-Up);
3208 Industrial Engines (3Z3371-Up)
Description of Change: Two new gaskets are used on water cooled exhaust manifolds for the above engines. The new gaskets are made of a different material and better resist coolant leakage into the exhaust manifold. The new gaskets provide additional material in critical sealing areas and eliminate the need for a metal flange.
Adaptable As: The new 7W1641 and 7W1642 Exhaust Manifold Gaskets are direct replacements for the former 8N587 and 2N2754 Exhaust Manifold Gaskets, respectively.
Use the following procedure to install the new gaskets and tighten the bolts and nuts to the correct torque specifications. See the illustration for location of gaskets and fasteners.
Exhaust manifold tightening sequence.
Procedure To Install New Gaskets
1. Install two new 7W1641 and four 7W1642 Exhaust Manifold Gaskets as shown in the illustration.
2. Install bolts (A, B, C and D). Install the nuts on bolts (B). Finger tighten the bolts in letter sequence.
3. Tighten eight bolts (B), that fasten the elbows (5) and (1) to the rear manifold (3) to a torque of 14 ± 7 N·m (10 ± 5 lb ft).
4. Tighten eight bolts (C), that fasten elbows (5) and (1) to manifolds (2) and (4), to a torque of 14 ± 7 N·m (10 ± 5 lb ft).
5. Tighten bolts (B) to a torque of 45 ± 7 N·m (32 ± 5 lb ft).
6. Tighten bolts (C) to a torque of 45 ± 7 N·m (32 ± 5 lb ft).
7. Tighten 16 bolts (A) to a torque of 45 ± 7 N·m (32 ± 5 lb ft).
8. Tighten two bolts (D), that fasten the rear manifold to the engine, to a torque of 100 ± 15 N·m (75 ± 10 lb ft).