Multiquip LS-500 - Manual (Page 39)

MAYCO LS400/LS500 PUMP — OPERATION AND PARTS MANUAL — REV. #6 (09/19/11) — PAGE 39
CLEANING THE LUBRICATION BOX
1. Remove the top cover and the drain plug (Figure 40)
located at the bottom of the box and fully drain the inside
of the box.
2. Once the box is drained, start the engine and stroke the
cylinder ( keep hands out of box) ten to fifteen times.
3. While stroking, spray water inside of the box to
thoroughly clean out all contamination (Figure 40).
4. When the box is clean replace drain plug, add new
lubrication and install the top cover.
1. The lubrication level should be checked everyday prior
to pumping and maintained at a height of 5 inches or
about ½ the concrete cylinder height. We recommend
using a 30-weight motor oil.
CYLINDER LUBRICATION BOX
Figure 40. Cleaning the Lubrication Box
LS400/LS500 PUMP — MAINTENANCE (PUMP)
ACCUMULATOR CIRCUIT
Figure 41. Accumulator
CHECKING ACCUMULATOR BLADDER PRESSURE
The normal accumulator charge pressure should be
approximately 1100 PSI. To check the accumulator pressure:
1. Start the engine and stroke the pump. The accumulator
pressure gauge (Figure 30) should read 1750 PSI.
2. To determine the actual accumulator PSI, stop the
engine and observe the pressure gauge. As the PSI
reading slowly decreases, it will reach a point where
there will be a sudden drop in the PSI. The PSI reading
should be taken just prior to this sudden drop. If you do
not read 1100 PSI, the accumulator may require charging
or bladder replacement.
When the pump cycles, a part of the stored oil is released
to the shuttle cylinder. This pressure release assures the
shuttle tube has enough force to shear the cylinder of
concrete passing from the concrete cylinder to the concrete
delivery line during the cycle phase.
Before checking lubrication level, follow lock out-tag
out procedures. Stop the engine and remove the
engine starter key.
2. As the rubber piston cups naturally wear, fine cement
particles will accumulate in the box. Once the concrete
paste reaches a height of about ½ inch from the bottom
of the box, drain and clean the lubrication box.
Improper accumulator charging can result in an
explosion causing serious injury or death! NEVER use
oxygen or compressed air to charge the accumulator!
Only qualified personal should perform this procedure.
Use only
dry nitrogen to
charge the accumulator.
Contact your Mayco
service department or your
local Hydac representative
for proper charging
procedure.
The accumulator circuit has two functions in the hydraulic system.
■ The accumulator circuit furnishes the hydraulic pressure
to cycle the shuttle tube.
■ The accumulator circuit also furnishes the pilot pressure
necessary to activate the hydraulic system.
The accumulator circuit is equipped with a
bladder type accumulator (Figure 41)
charged with 1100 PSI of dry nitrogen. The
accumulator stores one gallon of hydraulic
oil, which is, under 1750 PSI of pressure.
CAUTION - SAFETY GUIDELINES
DANGER - ACCUMULATOR CHARGING
When using the pump during freezing conditions,
completely drain the water box and cover the hopper
after pumping. Frozen liquid will restrict the piston travel
and cause
severe damage to the pump.
WARNING - FREEZING CONDITIONS