HARNESS ASSEMBLY 1248355 - Caterpillar

Illustration 1 g00898747
(A) Exhaust manifold with top exhaust port (four cylinder engines) (B) Exhaust manifold with side exhaust port (four cylinder engines)
Illustration 2 g00898748
(C) Exhaust manifold with top exhaust port (six cylinder engines) (D) Exhaust manifold with side exhaust port (six cylinder engines)Correct alignment of the exhaust manifold is necessary in order to prevent the possibility of a cracked manifold. Proper alignment of the exhaust manifold also allows the bolts or studs to expand.New exhaust manifolds are equipped with plastic ferrules to ensure correct alignment on the cylinder head. The position of the ferrules varies according to the exhaust port on the exhaust manifold. The plastic ferrules are supplied in a new exhaust manifold only. If a used exhaust manifold is being reinstalled on the cylinder head, carefully center the manifold while the bolts or studs are tightened.Use the following procedure to install a new exhaust manifold on the cylinder head.Note: Most engines are equipped with bolts. Older engines may have studs with nuts.
Ensure that the ferrules are installed in the correct positions in a new exhaust manifold before installation.On four cylinder engines with a top exhaust port (A), the ferrules are in positions 3 and 6. On four cylinder engines with a side exhaust port (B), the ferrules are in positions 2 and 5.On six cylinder engines with a top exhaust port (C), the ferrules are in positions 9 and 12. On six cylinder engines with a side exhaust port (D), the ferrules are in positions 8 and 11.
If the bolts or studs are reused, remove the old sealant from the threads. Apply 4C-4030 Thread Lock Compound or 9S-3263 Thread Lock Compound to the first three threads of the bolts or studs before installation.Note: New bolts have sealant that is applied to the threads by the manufacturer.
Install a new exhaust manifold gasket.
Use two bolts through the ferrules to install the exhaust manifold on the cylinder head. Install the remaining bolts in the exhaust manifold and finger tighten all of the bolts. If the engine is equipped with studs, install the exhaust manifold over the studs. Then install the nuts and finger tighten all of the nuts.
Tighten the exhaust manifold nuts or bolts gradually in the numerical sequence that is shown in the above illustrations to the proper torque.Torque for nuts or bolts ... 33 N m (24 lb ft)
Repeat the tightening procedure in Step 5 to ensure that all of the nuts or bolts are tightened to the correct torque.