Hydraulic Troubleshooting, is it Difficult?

The well designed and well manufactured Hydraulicworking when the machine stopped?
machinery is very reliable; it is going to give you a lot•    Go back to the information about the
of years of production without giving you trouble inmachine you collected before. Check the hydraulic
most cases. This sounds good, but reality is thatschematics, trace the path from the pump to the
even you give your hydraulic machinery the bestactuator, how many valves are there, what kind.
preventive maintenance, such as changing filters, oilTake into account that there are some components
on a regular basis, sometimes the machine is going tothat are common for different movements or
stop Typically, it will not be in a convenient moment,actuators, like pumps, relief valves, some directional
it may likely occur when you need it most, when youvalves, some flow controls.o    At this point, after
cannot stop production.comparing notes you should have in your mind two
When you are facing a situation like this, the betteror three or even more possible causes. Now is the
prepared you are, the faster you are going to takemoment to act. Let’s say you have two
your machine back working.possibilities, and then you need to think in how you
So, what do you need to do to perform a fastare going to perform a test to disprove or confirm
troubleshooting in your hydraulic machine that allowsone of them. To do so, you need to isolate the
you to come back to normal?hydraulic element and use a Flow meter with
I am going to discuss two different things, what topressure gauge and load valve built in (relief valve).
do before, and how to initiate some easyFor example: if it is a pump you are trying to
troubleshooting.eliminate, you connect the flow meter direct to the
When I say before, I mean when the machine isoutlet, start the machine and check the flow, first
working well, and you have time to work on thewithout load and then with it, closing the load valve.
following:If the reading of the flow at max pressure (setting
•    Learn Hydraulics. Yes, if you are not familiarof the machine) is around 90% of the flow without
with hydraulics, start from this point. If you want toload we can say that the pump is good, so the
resolve a problem fast, you need to learn howproblem is caused by the other element.
hydraulics works. If you have some knowledge, beOff course, all of the actions I described above are
sure of you know how all the hydraulic componentsquite general, but the idea is that in order to discard
work, how they handle FLOW, PRESSURE andor confirm that a hydraulic element is the cause; you
DIRECTION. How all of them are connected to eachneed to follow the path from the pump to the
other in your machine.actuator that stopped and perform the flow and
•    Gather as much information related to thepressure test adding an additional element like the
machine as you can, schematics, lists of components,relief valve after the pump, and so on until you get
manufacturers, catalogs, breakdowns, pressureto the cylinder.
settings and testing points.In brief, hydraulic troubleshooting is difficult but with
•    Familiarize with the machine, check thethe hydraulic knowledge, machine information and
information you have gotten out, how manyequipment (flow meter) is much easier and definitely
actuators (cylinders and motors), pumps andmuch faster. The last one is relatively easy to get,
different valves the system have.the second one is easy depending on the
When the situation occurs- don’t panic, and domanufacturer, and the first one is going to take more
the following:time but is the most worth it.
•    Talk to the machine operator; try to get asNote: If you do not have a Flow meter, you can use
much information as possible in order to get a cleara 5 gal bucket to discharge the flow with a relief
understanding about all the circumstances when thevalve and gauge timing with a watch, for example: If
stop happened. Was it at the beginning of the cycle?the bucket is filled in 15 secs, the flow is 5 x 60/15 =
In an intermediate point? Or which actuator was20 GPM.