Mega MMP4, Maintenance Manual

Page: 18 / 96

MMP4-CAT(T4)-MX-2
26 Feb 2014
SECTION 4
Basic Hydraulics System
4-5
INSPECTION
1. Check hydraulic cylinders for security, damage
and leaks.
2. Check hydraulic cylinder safety chains for
security, missing parts and damage.
3. Check hydraulic hoses and metering valves for
security, damage and leaks.
4. Check for proper operation and alignment.
REPAIR
Repair, adjust or replace as required.
HYDRAULIC FILTER
The spin on hydraulic oil filter is in the return to tank
hydraulic circuit. All hydraulic oil passing through the
system passes through the filter prior to the hydraulic
oil cooler. The filter is rated at 400 psi (2,758 kpa). The
filter is rated at 10 microns and the filter housing has
a built in bypass valve to bypass the filter element
when the inlet pressure is too high or the filter
becomes restricted.
INSPECTION
1. Inspect hydraulic oil filter mounting for security
and damage.
2. Check hydraulic filter for leaks and damage.
3. Check hydraulic filter assembly hose fitting
adapters for security and leaks.
REPAIR
Repair, adjust or replace as required.
HYDRAULIC OIL COOLER
The hydraulic oil cooler is attached to the front of the
engine radiator. The engine cooling fan draws cool air
through the oil cooler lowering the oil temperature.
The oil cooler is in the return to tank hydraulic circuit.
Built into the oil cooler is a bypass valve that allows
oil to bypass the cooler if the return oil pressures are
too great (e.g; when the hydraulic oil is cold). The oil
cooler and engine coolant radiator are protected by a
steel mesh guard to prevent damage to the cooler
and radiator.
INSPECTION
1. Check hydraulic oil cooler and radiator guard for
security and damage.
2. Check hydraulic oil cooler and fittings for leaks.
3. Check hydraulic oil cooler for blockage and
debris that may interfere with proper cooling of
oil passing through cooler assembly.
REPAIR
1. If cooling fins are dirty or plugged with debris,
remove, replace or clean cooler as required.
2. Tighten or replace leaking or damage adapter
fittings as required.
3. Replace radiator guard if damage is present.