Michco sc8000, Руководство по обслуживанию

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Hydraulic System 118 Service Manual – SC8000
Troubleshooting
General Troubleshooting
Problem Cause Correction
Fault code 34
displayed on the
LCD
Hydraulic temperature fault that sets when
hydraulic oil temperature exceeds 220 F for
15 seconds.
Clean the cooling fins on the
hydraulic oil cooler to ensure
adequate airflow through the cooler.
Fault code 39
displayed on the
LCD
Hydraulic filter fault, sets to warn operator
that oil filter is plugged and needs to be
replaced.
Note: Only activates when oil temperature
is above 100 degrees F (this prevents false
signal upon cold engine start up).
Replace hydraulic oil filter.
General Information Regarding Checking Hydraulic Pressures
Accurate measurements are the key to troubleshooting a hydraulic system. Once you obtain accurate
measurements you can compare them to the specifications to analyze a problem.
You can use digital tachometers, flow gauges or pressure gauges to troubleshoot the hydraulic system.
The pressure gauge should have a range of 0 to 3000 psi (see the
Special Tools
section) and have a Parker
Diagnostics connector number PD222. The most convenient way to check for oil flow is to check the RPM of
the motor that is performing poorly. Refer to the
Specifications
tables to determine the motor RPM. If the
motor speed is correct, the pump is producing the correct amount of oil flow. However, this does not mean
that if a motor is running too slow the problem is in the pump.
The following information should be used to check for correct motor RPM, system pressure and relief valve
settings. The readings are nominal figures and there will be variations due to manufacturing tolerances
and system oil temperature. If any reading varies greater than 20 percent, there will be a noticeable loss of
performance and the problem should be corrected.
Test Port Nominal Pressure Readings
Note: See the figure on the following page and the
Specifications
tables.
100 psi = 6.9 bar.
1. Insert the pressure gauge into the test port.
Note: The Lower Test Port (TP 4) on the Scrub Lift Cylinder is easier to access if you lower the
scrub deck.
2. Run the engine in high throttle position (2200 RPM) and allow the hydraulic oil to warm up.
• The bypass pressure is the pressure reading with no motor or cylinder operating.
• The operational pressure is the pressure range in which the motor or cylinders will operate.
• A much lower than normal bypass pressure could indicate a gear pump problem.
• If the bypass pressure remains the same after turning the function on, there could be a problem in
the control valve or circuit.