2006/08/14 Caterpillar

Industrial Engine:

3406 (S/N: 90U1-UP)

3406C (S/N: 6TB1-UP; 3ER1-UP)

G3406 SI TA (S/N: 4FD1-UP)

G3406 SI (S/N: 1RK1-UP)

Generator Set Engines:

3406C (S/N: 2AM1-UP; 4BM1-UP; 4ZR1-UP; KPS1-UP; 9ES1-UP; PFH1-UP; 1SS1-UP; 9PL1-UP; 4PM1-UP; C2G1-UP; C5G1-UP; C8G1-UP; 1LS1-UP; 8FS1-UP; 2WB1-UP; 4RG1-UP; 4JK1-UP)

3408 (S/N: 78Z1-UP)

3412 (S/N: 81Z1-UP)

3304 DI (S/N: 3TC1-UP; 83Z1-UP)

3306 DI T (S/N: 5JC1-UP; 85Z1-UP)

3306 (S/N: 7KF1-UP)

3306B DI T (S/N: 1DG1-UP)

3406 DI T (S/N: 75Z1-UP)

Marine Engines:

3406C (S/N: 4TB1-UP; 91U1-UP)

Engine News SEBD9397, May 2006, "A New Piston Cooling Jet Assembly Has Been Released". Disregard this article. See the article that follows.

Description of Change: New piston cooling jet assemblies are used on these engines. The new tube assemblies provide more clearance between the tube assembly and the inside of the piston skirt than the previous tube assembly. This increased clearance will prevent the new tube from contacting the piston, which could result in a broken piston cooling jet assembly.

Adaptable To: The new 290-6568 Tube As was released for Optional Service Replacement for 7W-4990 Piston Cooling Jet As for 6 cylinder engines. 290-6568 Tube As is intended for use on older cylinder blocks that have the 3/8-16 threads in order to clear the 9Y-9889 Piston Body As, 9Y-7212 Piston Body As, and 9Y-4004 Piston Body As pistons. The new 290-6567 Oil Jet Tube As is a direct replacement for the former 151-5929 Piston Cooling Jet As. The former piston cooling jet assembly has been cancelled. Refer to Table 1 for additional information on the 290-6567 Oil Jet Tube As.

Table 1

Serial Number Effectivity for the 290-6567 Tube As- Oil Jet
Industrial Engine
Sales Model	Serial Number
3406B	S/N:6TB24054-UP
Generator Set Engines
3406B	S/N:2WB18378-UP
3406C	S/N:4ZR08539-UP
3406C	S/N:2AM00044-UP
3406C	S/N:4BM00015-UP
3406C	S/N:1DZ12039-UP
Marine Engines
3406B	S/N:4TB09221-UP
3406C	S/N:1SS01599-UP

The improved clearance is effective with the 0R-4515 Cylinder Kit and the 0R-2694 Cylinder Kit. The cylinder packs have a date code of "D22M02Y06" ( 22February 2006) on the packing list. Cylinder Packs with a date code prior to 22February 2006 should use the new 290-6567 Oil Jet Tube As or the 290-6568 Tube As in order to obtain a minimum clearance of 0.80 mm (0.0315 inch).

Check the clearance between the piston and the cooling jet with a 0.80 mm (0.0315 inch) piece of metal wire. You should have acceptable clearance if the metal wire loop passes between the piston skirt and the cooling jet tube with the piston at the bottom center position.

The improved clearance is effective with the following short blocks and long blocks. Refer to Table 2. The blocks must have a Julian Date Code of "06906" ( 10March 2006). The Julian Date Code is located on the left side of the engine block. The Julian Date Code consists of five digits. The first three digits indicate the day of the year. The last two digits indicate the year of manufacture. For example, the Julian Date Code for 9March 2006 is "06806".

Table 2

Long Blocks
Model	Part Number
3406A DI	0R-3711
3406B Dual Spring Cylinder Head	0R-3752
3406B Single Spring Cylinder Head	0R-3751
Short Blocks
3406A	0R2545
3406B	0R4812