Hydraulic Fluid/Filter Change - Terex PT-100G Forestry Service Manual

Compact Track Loader
4. Maintenance

Hydraulic Fluid/Filter Change

Hydrostatic components require extremely clean oil in
order to have a long service life. Use extreme caution
when changing the hydraulic oil. Introducing dirt or
debris could be detrimental to the hydraulic system.
Terex recommends service intervals of 1000 hours for
hydraulic fluid and 250 hours for hydraulic fluid filters.
To change the hydraulic fluid:
1. Shut the machine down as described in 5.13 of the
operations manual.
2. Allow machine to cool, then release any residual
pressure in the hydraulic system as described in
4.6 of the operations manual.
3. Lower the middle belly pan to access the tank
drain plug as shown.
4. Remove the drain plug using the correct size allen
type wrench, or allen socket to, avoid damaging
the drain plug (fig. 4-46, item A).
5. Drain the hydraulic fluid into a suitable catch
container.
6. Locate the hydraulic filters underneath the
cab on the left side of the machine
(fig. 4-47, item's B).
7. Thoroughly clean around the filters to prevent dirt
or debris from entering the system and remove the
filters by hand or with a strap as required.
8. Check to make sure the filter gaskets are still
present on the old filters. If not, check the filter
heads to make sure they are free from old gasket
material prior to installing the new filters.
9. Prepare the new filters by rubbing a small amount
of fresh hydraulic oil onto the filter gasket surface
and then threading them onto their respective filter
heads. Tighten filters by hand as instructed by the
label located on the filter or filter box.
10. Install the hydraulic system drain plug and tighten.
11. Remove the hydraulic reservoir filler cap (fig. 4-48,
item D). Slowly fill the hydraulic system with
Mobil DTE 10 Excel Series, or equivalent, until
visible in the sight gauge and the full mark has
been reached (fig. 4-48, item C).
Note: When checking or adding to the hydraulic fluid
level, do so with the lift arms in the lowered position. If
the level is checked with the lift arms in the raised
position, an inaccurate reading will result.
Note: When adding hydraulic fluid, add fluid slowly
until it is visible in the sight gauge. Once visible, add
fluid in one quart increments until the full mark has
been reached.
4-46
4-47
FULL
C
4-48
12. Install and secure the hydraulic reservoir filler cap.
13. Start the machine and operate all hydraulic circuits
to work any trapped air out of the system.
• Drive the machine forward and backward.
• Raise and lower the lift arms(unloaded).
• Dump and curl bucket/quick attach.
14. Once you have purged the air from the system,
check the level on the hydraulic fluid level sight
gauge. If the level is low repeat step 11 and 12 to
complete the procedure.
4-14
A
B
LOW
D