MULTIQUIP MAYCO Series Operation Manual page 28

3. When pumping long distance or pumping stiff mixes,
you can expect a drop in volume compared to shorter
lines and wetter mixes due to the change in valve
efficiency or cavitation.
4. Leaking manifold seals or hose coupling gaskets which
leak water can cause separation and subsequent
jamming at that point.
5. Damaged hoses with internal restrictions can cause
blockages.
6. If a blockage occurs in a hose, "walk the hose" until
you find the point of trouble. The hose will be soft
immediately past the blockage. If this happens at the
start, disconnect the hose at the first coupling past
the blockage.
Elevate the hose at that point with the blockage area
hanging down.
Using a hammer, you can pound the down-stream
edge of the packed area until it is free to flow. Shake
all of the sand and gravel out to the end of the hose.
Before reconnecting the hose, start the pump and run
a small amount of concrete out to the end of the hose.
This will assure that all of the separation is out of the
hose.
CAUTION
When disconnecting hoses, use extreme CAUTION!
The hose is under pressure.
7. Clearing a Plugged Manifold
The manifold is plugged if the volume at the discharge
end of the hose stops, and the hose is soft. The drive
belts will start to slip and the engine will lugdown.
Follow steps below to unplug a clogged manifold.
DANGER
Due to pressure build-up inside the manifold, great
care must be taken when clearing a plugged manifold
a. STOP the pump. Switch OFF the engine.
b. DO NOT open any of the delivery system joint
clamps.
c. The senior operator must warn all others to stand
PAGE 28 — MAYCO C30HDGA CONCRETE PUMP • OPERATION MANUAL — REV. #1 (09/09/19)
at least 20 feet away from the pump and turn their
heads away from the manifold.
d. The operator must position himself/herself away
from the hinged side of the manifold.
e. Wearing safety glasses, grasp the clamp arm
weldment and carefully pull it open to the primary
(safety) position. STOP count to 20. This will allow
the pressure to release.
f. After the pressure has been released, open
the clamp arm weldment and swing the hinged
discharge cone open.
g. Remove blockage with a round 2-foot length of
reinforcing steel rod. Flush the manifolds with
water. Make sure the (3" x 2") reducer is clear of
any blockage before closing the discharge cone.
h. After the blockage has been cleared and the pump
manifold has been thoroughly flushed with water,
close the hinged discharged cone and lock into
place.
i. Before reconnecting hose to the reducer, start the
engine and pump two or three shovels of concrete
through the reducer. This will insure that all the
blockage has been cleared.
j. Shake out around 2 feet of concrete before
reconnecting hose to pump. After this is done,
connect hose to pump and resume the pumping
operation.
8. Avoiding Setting of the Mix in the System
To avoid setting of the concrete mix in the system when
waiting more than 30 minutes between concrete loads,
flush the system depending on job factors (such as
presence of accelerators and job site temperature) and
your particular mix design.
CLEARING A MIX FROM THE SYSTEM
If, for any reason, the mix should set up in the system, the
following procedure is suggested:
CAUTION
When disconnecting hoses, use extreme CAUTION!
The hose is under pressure.
OPERATION