D379, D398, D399 INDUSTRIAL & MARINE ENGINES Caterpillar

1. Remove the bolts (2) that hold manifold to housing (1).

NOTE: On the D399 Engines, the intake manifold can be removed as one section for each two cylinders. Remove spacer that connects the manifolds.

2. Remove the clamp (4) that holds the oil line for the oil cooler to the manifold.

3. Remove bolts (3) that hold manifold to the cylinder heads. Remove the intake manifold.

Install Intake Manifolds

1. Install new manifold gaskets.

2. Put intake manifold (1) in position on engine. Install the bolts that hold manifold to cylinder heads.

NOTE: On the D399 Engines, the manifolds can be installed as one section for each two cylinders.

3. Install the bolts that hold manifold to housing. Install the clamp that holds line for the oil cooler to the manifold.