ROD AS 2099993 - Caterpillar

Instrument Tests
The 4C-4890 Fittings Group can be used to make pressure tests on the vibratory system. Before any tests are made, visually inspect the complete hydraulic system for leakage of oil and for other parts that are damaged. For some of the tests a magnet and a mm (in) measuring rule are usable tools. The 4C-4890 Fittings Group has JIC connectors and NPT threads on the fittings. JIC-to-metric and NPT-to -metric adapters must be used as necessary when checking pressures on this machine.When any test is made on a machine system, the hydraulic oil must be at the normal temperature for operation.Pump Efficiency Check
For any pump test at a given rpm, the pump flow at 690 kPa (100 psi) will be larger that the pump flow at 6900 kPa (1000 psi). The difference between the pump flow of the two operating pressures is the flow loss.Method of finding flow loss: Flow loss when expressed as a percent of pump flow is used as a measure of pump performance.Example of finding percent of flow loss: If the percent of flow loss is more than 10%, pump performance is not good enough.*Numbers in examples are for illustration and are not values for any specific pump or pump condition. See Specifications for pump flow of a new pump at 690 kPa (100 psi) and 6900 kPa (1000 psi)Machine Test
Install a Flow Meter. For Formula I, measure pump flow at 690 kPa (100 psi) and at 6900 kPa (1000 psi) with the engine at high idle rpm. Bench Test
If the test bench can be run at 6900 kPa (1000 psi) and at full pump rpm, find the percent of flow loss using Formula I.If the test bench cannot be run at 6900 kPa (1000 psi) and at full pump rpm, run the pump shaft at 1000 rpm. Measure the pump flow at 690 kPa (100 psi) and at 6900 kPa (1000 psi). Use these values in the top part of Formula II. For the bottom part of the formula, run the pump shaft at 2000 rpm. Measure the pump flow at 690 kPa (100 psi). Relief Valve Pressure Test
Make reference to on first page of Testing And Adjusting.
On Left Side of Screed
(1) Gauge port [marked "gauge" on manifold]. (2) Vibratory control manifold.
The following tests and adjustments are performed with the machine engine operating. These tests are done away from the operator's station, so two people must be working. One person performs the tests and adjustments, and the other should be at the controls. This will help prevent accidental movement of the machine.
1. Assemble the tools listed in the chart above.2. Attach the pressure gauge (8T-0859) on the vibratory control manifold gauge port (1).3. Engage the parking brake.4. Start and run engine.5. Place both vibratory control switches (on the operator station and right hand screed station) in the ON position.
Operator's Station
(3) Flow control adjusting knob.6. Turn flow control adjusting knob (3) full clockwise.7. Slowly propel the machine forward. The vibrators will not run