2013/02/08 Caterpillar

Truck Engines:

C-15 (S/N: MBN1-UP; 6NZ1-UP; 9NZ1-UP)

C-16 (S/N: 7CZ1-UP)

C-18 (S/N: MDP1-UP)

C15 (S/N: SDP1-UP; BXS1-UP; MXS1-UP; NXS1-UP)

C16 (S/N: G1D1-UP)

Truck Engine News SEBD6873, 26 November 2012, "A Modified Procedure Is Now Used to Seal the Mating Surfaces of the Cylinder Block and Spacer Plate on Certain C-18 Engines". Disregard this article. Refer to the article that follows.

A modified procedure is now used to provide a better seal between the cylinder block and spacer plate on the engines listed above.

The repair is adaptable back to the first production of the listed engines.

Table 1

Parts List
Quantity	Part Number	Description
1	227-1204	Gasket
1	4C-9505	Gasket Sealant
1	6I-4421	Spacer Plate

Repair Procedure

ReferenceDisassembly and Assembly, "Cylinder Head - Remove and Install"

Note: If the gasket is not damaged, the existing 227-1204 Gasket can be used.

Note: If the spacer plate is not damaged, the existing 6I-4421 Spacer Plate can be used.

1. Remove the cylinder head.

2. Remove all previous material from mating surfaces.

3. Clean all surfaces and dry all surfaces with a solvent that is free of residue.

4. Remove the cap and apply the 4C-9505 Gasket Sealant with the applicator to the surface of the gasket that will contact the engine block.

   Note: Loctite 5923 or Permatex Aviation Form-A-Gasket No.3 Sealant can be used as alternative sealants.

5. When the sealant is used as a dressing for the gasket, spread the product with a spatula to a uniform film on the surface of the gasket that will contact the engine block. Ensure that the gasket sealant is spread evenly over the surface of the gasket. Position the gasket on the cylinder block.

6. Install the spacer plate over the gasket that is located on top of the cylinder block.

7. Install the gasket that was located between the spacer plate and the cylinder head over the spacer plate.

8. Install the cylinder head.

9. Once the repairs have been completed and the sealant has cured, run the engine in order to ensure that there are no leaks.

Cleanup

1. The sealant can be removed from metal surfaces with isopropyl alcohol. If the sealant has been dried for a long time or at high temperatures, cover the sealant with alcohol and allow the sealant to soften overnight.

2. Clean hands.