Jacobsen R-311 Parts & Maintenance Manual Download

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MAINTENANCE 4

4.12 HYDRAULIC HOSES________________________________________________________________________

1. Always lower implements to ground, disengage all drives,

engage parking brake, stop engine, and remove key before
inspecting or disconnecting hydraulic lines or hoses.

2. Check visible hoses and tubes daily. Look for wet hoses or oil

spots. Replace worn or damaged hoses and tubes before
operating the machine.

3. The replacement tube or hoses must be routed in the same

path as the existing hose, do not move clamps, brackets, or ties
to a new location.

4. Thoroughly inspect all tubes, hoses, and connections every 250

hours.

IMPORTANT:

The hydraulic system can be permanently

damaged if the oil becomes contaminated.

Before

disconnecting any hydraulic component, clean the area around
the fittings and the hose ends to keep impurities out of the
system.

a. Before disconnecting any hydraulic component, tag or mark

the location of each hose then clean the area around the fit-
tings.

b. As you disconnect the component, be prepared to assem-

ble plugs or caps to the hose ends and open ports. This will
keep impurities out of the hydraulic system and also prevent
oil spills.

Make sure “O” rings are clean and hose fittings are properly

seated before tightening.

d. Keep the hose from twisting. Twisted hoses can cause cou-

plers to loosen as the hose flexes during operation resulting
in oil leaks.

e. Kinked or twisted hoses can restrict the oil flow causing the

system to malfunction and the oil to overheat and also lead
to hose failure.

4.13 HYDRAULIC OIL ___________________________________________________________________________

Refer to

Section 6.3

for specific maintenance intervals.

Drain and replace the hydraulic oil after a major component failure, if
you notice the presence of water or foam in the oil, or a rancid odor
(indicating excessive heat).

Always replace the hydraulic filter when changing oil.

To change hydraulic oil:

1. Clean the area around the oil cap to prevent impurities from

entering and contaminating the system.

a. Oil temperature should be between 60° to 90°F (16° to

32°C). Do not check oil level when oil is hot.

b. The main oil tank level should be 2 inches below filler neck.

Do not overfill.

2. Drain and replace the hydraulic oil yearly or after a major

component failure, or if you notice the presence of water, foam,
or a rancid odor.

3. Remove drain plug from bottom of main tank and loosen or

remove breather cap. Check and clean the breather cap,
replace as necessary.

4. After oil has drained install drain plug and fill with Jacobsen

Hydraulic oil.

5. Purge air from system.

6. Operate all mower functions for about 5 minutes to purge air

out of the system and stabilize the oil level. Fill tank to full level.

WARNING

To prevent serious injury from hot, high pressure oil, never use
your hands to check for oil leaks, use paper or cardboard.

Hydraulic fluid escaping under pressure can have sufficient force
to penetrate skin. If fluid is injected into the skin it must be
surgically removed within a few hours by a doctor familiar with this
form of injury or gangrene may result.

NOTICE

Care must be used at all times to avoid any contamination of the
hydraulic system. Follow recommended maintenance practices
and adhere to scheduled intervals for hydraulic oil and filter
changes. Introduction of any type of contamination may result in
operating issues by causing valves to stick or leak internally.