Mudd-Ox XL - Page 67

67
Hydrostatics Cont.
19. Now remove any potential air pockets in the hydraulic system. With the hydraulic system correctly reassem-
bled, start the Mudd-Ox and run at 1,500 RPM for a minute. Get the oil to operating temperature. Then, slowly
raise the RPM’s a few hundred at a time. If there is a “rattle” noise coming from the hydraulics, that is air in
the system. Immediately bring the RPM to idle for a minute. Then try again. During this time, have another
mechanic monitor the hydraulic oil tank level. If the oil level falls below the sight glass, fill up immediately.
20. Once the machine will go through the entire RPM range in neutral without rattling, you may begin with the
control levers. Slowly move the control levers forward approximately an inch. Run for a minute. If there is no
air, continue moving forward in steps. If the hydraulics begin to rattle, bring back to neutral for a minute then
try again. Repeat for control levers in reverse. Then slowly move control levers backward. Continue to move
the control levers with varying degrees of stroke. Note: It is very important to not “drive” against the air as
this will damage the pumps. Once the Mudd-Ox can be driven in both directions without any air, shut off and
let the oil temperature completely cool down.
21. Carefully lower the Mudd-Ox to the ground and reinstall any components removed to gain access to the oil
system in prior steps.
22. Now, proceed to get inside the vehicle and start up. Get to operating temperature. Slowly begin to drive
around a controlled environment such as flat ground. Listen and feel for air in the hydraulic system; the ma-
chine will feel “tight” if the pumps have air. If there is air, do not attempt to drive against it. Work the control
levers as described in step #20.
23. Once the Mudd-Ox can be driven on flat ground in both directions without any air, attempt to drive on small
grades both up and down. Also attempt to counter-rotate the Mudd-Ox by pushing the control levers in oppo-
site directions. If there is no air, the oil change is complete.