DA Form 2440, Suggest ion Title: Truck, 20 Ton Dump, Relocation of Hoist Filter Assembly, 2222-C-77
maintenance.
Also keep in mind, the fact that sharp hose bends and 90° fittings in a hydraulic restrict oil flow, so relocate
the oil filter in a location where gentle hose bends and, at the maximum, 45° fittings can be used.
-A location inside of the
frame should be evaluated.
Construct a short, heavy L-bracket to match and hold the oil filter head with the least distance possible from the
frame.
The L-bracket should have at least two heavy triangular vertical gussets between the legs to provide strength.
Remember the bracket has to support not only the filter filled with oil, but the weights of the connecting hose lines, the
bend forces of the hose lines and the forces exerted by the oil pressure flowing through these bends which want to
straighten them out.
Now, add to this the vibration of a washboard roadway and the chuckholes encountered by the truck
when empty."
e.
The correct method for drivers and mechanics to gain access to the hydraulic hoist system components behind
the cab is as follows:
(1)
Hoist dump body and disengage the OSHA Maintenance Struts on each side.
Place the free end of the
struts into the truck frame boxes, while lowering the body.
For added safety, now, place a minimum 4'x 4 timber wedged
into the junction between the dump body rails and the subframe rails.
(2)
The easiest method for personnel to gain access to behind the cab components is to begin with the right
foot on the bottom box step and right hand on the cab grab rail.
Next, place the left foot on the top of the buttery box and
add the left hand on the cab grab rail.
Now, let go of the grab rail with the right hand and swing from the side of the cab to
rear of the cab, landing with the right foot on the top of the dump body subframe top flange.
(3)
The above system of mounting avoids the necessity for personnel to step on the hoist filter support bracket
to gain access to the behind cab hydraulic components.
Use of the support bracket as a step will contribute .o cracking
and leaking of the hoist filter return pipe nipple at the hydraulic reservoir tank.
159