Trouble Shooting Hydraulics

To avoid trouble inspect your system daily and apply the four senses:

Sight – Hearing – Touch and Smell.

Look at oil filter condition indicators, oil level in tank and check pipework for leaks.
If oil in tank has a milky appearance it is probably saturated with air or water. In either case your hydraulic system is in for trouble. Test oil by heating a spoonful, with a cigarette lighter.
Crackling will denote presence of water. If oil clears of milkiness, your oil is contaminated with water. Dump and replenish with fresh oil, or filter with special elements.

Listen for unusual sounds.
When the supply of fluid is insufficient to meet demands of pump, the pump goes into a state of hydraulic shock described as cavitation. The pump will emit a rumbling sound like pumping gravel.
Check that the suction valve is fully open and suction strainers are clean.
Feel around the system. If any part is hotter than hand hot, check that cooler is working efficiently. If temperature exceeds 60 deg.C the oil working life decreased. Oil oxidises slowly under 49 deg.C. Over this the rate of oxidation is double for every 10 deg.C. Oxidation causes sludge to form, reduce clearances, causes corrosion and creates more heat.
A lot can be learned by the “smell” of oil. If it is burned, check out pump suction pipes and valves, or air bubbles in systems.
The system is set up during commissioning and should not require adjusting.
The system requires very little attention apart from lubrication. Hydraulic systems operate on oil flow and pressure. Flow gives rotation or actuation speed and pressure gives torque or linear force. The fluid is the “life blood” of the system and should be continuously monitored to afford reliability and good life from components.
The hydraulic pump is always the most vulnerable to wear. So continually check the filters and oil level to keep system clean and cool.

* Should pressure gauge or ammeter show incorrect readings or anything unusual occur – consult supplier.
This document is not intended as an instruction manual for non trained persons.
Only suitably qualified persons should work on hydraulic systems.