Looking for a few ideas, working on a 953C 2ZN01943. Warning lights came in and Cat was called out to Inspect. They said the charge pump was bad. The customer had Cat replace the charge pump. Nothing was repaired. Machine runs fine for about 10 minutes and it starts acting up. Hooked a gauge up to charge pressure tap. Starts out around 400PSI but as it is operated drops off to under 300PSI. Removed the rear belly pan. Hooked gauges up to each case drain port. 5lbs on the left side and 9LBS on the Right side. Then hooked gauges up to each drive pump through the floor. 9LBS on the Right and 0PSI on the left. Checked the drive pressure at the block below your left foot thru the floor. 6200PSI on forward on the left rear corner port and 5800PSI on the right rear corner port in reverse. On the left front corner port the pressure was 6200PSI in Forward and on the rt front corner port it was 6200PSI in reverse. Cut both filters apart with no signs of metal. Please help
How are the hydraulics working they use common oil and a problem can spread to the drive. Case drain pressure is relative to drive loop leakage. Debris from bad charge pump might have entered and damaged the drive loop circuit. Best I can diagnose from this distance. Later Bob
Hello, Did you ever come up with a resolution to this issue? Hello, Have you come up with a solution to your issue? We have a Cat 953C that after it heats up and is put under load throws the pump pressure light, which then proceeds to shutting the machine down. Tested the charge pump and it looses pressure. Any help would be greatly appreciated. Thanks!