PUMP GP-PISTON & GEAR 1838289 - Caterpillar

Procedure
Grease is under high pressure.Grease coming out of the relief valve under pressure can penetrate the body causing injury or death.Do not watch the relief valve to see if grease is escaping. Watch the track or track adjustment cylinder to see if the track is being loosened.Loosen the relief valve only one turn.
Move the machine forward. Allow the machine to stop without the use of the service brakes. Adjust the tracks while you are in the machine's typical operating conditions. If packing conditions prevail on the workplace, the tracks should be adjusted with packing material.
Illustration 1 g00040335
Do not attempt to tighten track when dimension (1) is 138 mm (5.4 inch) or more.Contact your Caterpillar dealer for track service or instructions.
Illustration 2 g00040329
If a machine does not have carrier rollers, the sag in the track is measured between the sprocket and front idler (2). The correct adjustment of dimension (2) is 115 10 mm (4.5 0.4 inch) for machines with the STD undercarriage.The correct adjustment of dimension (2) is 127 10 mm (5.0 0.4 inch) for machines with the LGP undercarriage.
Illustration 3 g00104000
If the machine is equipped with a carrier roller, calculate the average of dimension (3) and dimension (4). The correct average value is 65 10 mm (2.6 0.4 inch).Loose Track Adjustment
Remove the access cover.
Illustration 4 g00104001
Add multipurpose grease (MPGM) through track adjustment valve (5). Add the MPGM until dimension (2) is correct.
Operate the machine back and forth in order to equalize the pressure. Allow the machine to coast to a complete stop. Do not use the brakes.
Remeasure dimension (2). Repeat Steps 2 and 3 until dimension (2) is correct.
Install the access cover.Tight Track Adjustment
Illustration 5 g00104002
Remove the access cover.
Loosen relief valve (6) by one turn of 360 degrees. Allow the grease to escape.
Close the relief valve.
Add MPGM through track adjustment valve (5). Add grease until dimension (2) is correct.
Operate the machine back and forth in order to equalize the pressure. Allow the machine to coast to a complete stop. Do not use the brakes.
Remeasure dimension (2). Repeat Steps 4 and 5 until dimension (2) is correct.
Install the access cover.