Technical
Hydraulic systems have now been commonplace on grounds maintenance equipment for many years, and not just on large equipment. From pedestrian machines to high-end ride-on equipment and tractor mounted mowers, hydraulic drive systems seem to have become the designers’ choice.
Jim Whitton continues his machinery series
I
can understand this because, generally speaking, hydraulic drives are very reliable, require far less running mechanical belt and chain drives and,
Dual drive HST system on pedestrian mower
more operator misuse without breaking. However, as with all things, they do have a “down side”. Because these systems require be overlooked or not carried out correctly. inadequate or incorrect hydraulic system machine, but believe me when they do strike, they can be catastrophic, unexpected and extremely expensive to repair. I recently came across a fairway mower that had sustained an internal hydraulic component failure in of failure because debris is then circulated around most of the other components in the circuit, damaging them as well. In this case, From my experience, this type of repair is system and even other subsystems that share thoroughly to prevent the expensive new components being damaged on start-up by debris hiding in some nook or cranny being process is carried out, there is always the
to provide a warranty with such a repair, so many don’t. It’s not surprising then that major repairs such as this can easily render the machine beyond economical repair. Catastrophic failures are obvious; the machine simply fails to operate. The other symptom of not maintaining the hydraulic system properly but will eventually result in the machine especially when hot. This type of problem is normally associated with debris in the internal wear of components or more likely introduced into the system from outside.
Here is a key fact:
and other foreign material. In today’s high pressure systems, clearances in valves are very small making the control of easy to see how correct maintenance is also super important. The second most common cause of
this is, some mineral based mono-viscosity temperature when you consider that most modern car engines run with oil temperatures temperatures of systems must not constantly
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