2006/11/06 Caterpillar

Engine:

3508B (S/N: S2A1-UP; S2B1-UP; S2D1-UP; S2E1-UP; S2F1-UP)

3512B (S/N: S2G1-UP; S2H1-UP; S2J1-UP; S2K1-UP; S2L1-UP; S2M1-UP; S2N1-UP; 1PW1-UP)

3516B (S/N: S2P1-UP; S2R1-UP; S2S1-UP; S2T1-UP; S2W1-UP; S2X1-UP; S2Y1-UP; S2Z1-UP)

Description of Change: Improvements have been made to water lines groups for the above listed marine diesel engines. A brass plug has replaced a zinc plated plug in order to prevent corrosion. The brass plug will also stop leakage. A new lower water tube allows the use of a zinc rod assembly.

Adaptable To: The following changes have been made to the 249-2846 Water Lines Gp :

• The 256-7335 Elbow has been cancelled and replaced by the 297-5439 Elbow .

• The new 297-5439 Elbow allows the use of the 116-7011 Zinc Rod As and a 6V-9027 O-Ring Seal .

• A 287-7296 Brass Plug replaces the 9S-4185 O-Ring Plug on the 233-9776 Elbow .

The following changes have been made to the 278-7527 Water Lines Gp :

• The 256-7335 Elbow has been cancelled and replaced by the 297-5439 Elbow .

• The new 297-5439 Elbow allows the use of the 116-7011 Zinc Rod As and a 6V-9027 O-Ring Seal .

• A 287-7296 Brass Plug replaces the 9S-4185 O-Ring Plug on the 278-7526 Elbow .

The changes are adaptable to the marine diesel engines that are listed above. Serial number effectivity is listed in Table 1.

Table 1

Serial Number Effectivity
Sales Model	Serial Number
3508B	S/N:S2A00128-UP
	S/N:S2B00338-UP
	S/N:S2D00182-UP
	S/N:S2E00602-UP
3512B	S/N:1PW00044-UP
	S/N:S2G00118-UP
	S/N:S2H00253-UP
	S/N:S2J00385-UP
	S/N:S2K00267-UP
	S/N:S2L00547-UP
	S/N:S2M00163-UP
	S/N:S2N00122-UP
3516B	S/N:S2P00108-UP
	S/N:S2R00295-UP
	S/N:S2S00254-UP
	S/N:S2W00112-UP
	S/N:S2X00545-UP
	S/N:S2Y00111-UP
	S/N:S2Z00130-UP

Illustration 1	g01322689
249-2846 Water Lines Gp Right side view (1) 116-7011 Zinc Rod As (2) 6V-9027 O-Ring Seal (3) 297-5439 Elbow

Illustration 2	g01322690
249-2846 Water Lines Gp Left side view (1) 116-7011 Zinc Rod As (2) 6V-9027 O-Ring Seal (3) 297-5439 Elbow (4) 287-7296 Brass Plug (5) 6V-6609 O-Ring Seal (6) 233-9776 Elbow

Illustration 3	g01321772
Typical example of zinc rod assembly (7) Shoulder (8) Threads

1. Apply 9S-3263 Thread Lock Compound to shoulder (7) of a new zinc rod. Do not apply sealant to threads (8) of the rod.

2. Screw the zinc rod into the plug.

Note: Lightly lubricate the bores for the zinc rods and the plugs with glycerin.

Torque for the zinc rod ... 2.25 ± .25 N·m (20 ± 2 lb in)