COMPRESSOR GP-REFRIGERANT 4495728 - Caterpillar

Illustration 3
New camshaft design with setscrew and screen.
(1). 6V-5135 Setscrew
(2). 7C-2568 Screen Assembly
(3). 3406 Fuel Pump Camshaft
The injection pump group part number is stamped on the top face of the injection pump housing. If any of the listed part numbers are found, the 7C-2568 Screen Assembly and one 6V-5135 Setscrew are required. The 7C-2568 Screen Assembly should be tightened to 3 _b1_ 1 N_b7_m (27 _b1_ 9 lb in). The 6V-5135 Setscrew should be tightened to 21 _b1_ 7 N_b7_m (16 _b1_ 5 lb ft).
Illustration 4
New camshaft design with two setscrews.
(1). 6V-5135 Setscrew
(2). 3406 Fuel Pump Camshaft
For all other 3406 NSFS Injection Pump Groups using camshafts with 7/16 threaded cross-drilled oil passages, two 6V-5135 Setscrews are required.
3408/12 Non-NSFS Camshafts
Pitting, spalling, and wear can occur on the lobes of the 4N-0599 and 4N-0602 Camshafts in the fuel injection pump groups for 3408 and 3412 Engines respectively. This problem has been found in the paths where the rollers for the 3S-9736 Lifter Assemblies travel over the camshaft lobes.
If pitting, spalling, or wear is encountered on the camshaft lobes, Caterpillar recommends installing a new camshaft (the same part number) and different lifter assemblies. Along with a new camshaft, install 8N-6981 Lifter Assemblies instead of the original 3S-9736 Lifter Assemblies. The 8N-6981 Lifter Assemblies have wider rollers, which will reduce the stress placed upon the camshaft lobes. Thus, the components will have longer service life.
Note: Do not reinstall a used camshaft with new 8N-6981 Lifter Assemblies unless the fuel system was originally equipped with 8N-6981 Lifter Assemblies.
For additional information, refer to Service Magazine; September 28, 1987; Page 12; New Steel Fuel Injection Pump Lifters Should Not Be Mixed With Aluminum Lifters 3400 Family of DIT Engines.
Notes:
SEBF8295-05 CATERPILLARAE A92003 Caterpillar