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14
H5-991-406A
Method #1 (system head pressure less than 2
psi)
a.. Install. the. valve. plate. (16). but. without. the. outlet. valves.
installed.(or.else.remove.the.outlet.valves;.leave.the.seats.
installed).onto.the.cylinder.housing..Tighten.the.two.socket-
head.screws.(41).
b.. Fill.the.reservoir.with.appropriate.Hydra-oil.to.the.fill.port.
c.. With.a.blunt.pointer.(eraser.end.of.pencil),.reach.in.through.
each. outlet. valve. port. and. push. the. follower-diaphragm.
backwards..Note.the.air.bubbles.coming.out.at.the.oil.fill.
port..Now.turn.the.shaft.about.1/.turn.
d.. Repeat.depressing.diaphragms.and.rotating.shaft.(approx..
4-6.times).until.no.more.air.bubbles.escape.and.the.oil.has.
dropped.about.1.inch.(5.mm).from.the.top.of.the.fill.port..The.
hydraulic.cells.are.now.primed..Replace.the.oil.fill.cap.
e.. Install.outlet.valve.assemblies.in.each.outlet.valve.port...See.
Parts.Manual.for.correct.assembly.order..You.may.have.to.
tip.pump.(head.upward).in.order.to.keep.the.valve.centered.
on.the.seat.and.allow.the.retainer.to.fit.all.the.way.into.port.
flush..
f.. Install.manifold.(6).and.complete.installation.
Alternative Method #1:
With.the.pump.horizontal,.and.the.fluid-end.head.removed,.fill.
the.reservoir.with.the.appropriate.Hydra-oil.for.the.application..
Have.a.catch.basin.for.oil.that.leaks.from.behind.the.diaphragms.
when.priming..Catch.the.oil.and.dispose.of.it.properly;.
do not
reuse it.
a.. All. air. in. the. oil. within. the. hydraulic. piston. behind. the.
diaphragms.must.be.forced.out.by.turning.the.shaft.(and.thus.
pumping.the.piston)..A.shaft.rotator.is.included.in.the.Hydra-
Cell.Tool.Kit..Keep.pressure.on.the.diaphragms.while.turning.
the.shaft.until.a.bubble-free.flow.of.oil.comes.from.behind.
all.the.diaphragms..Maintain.the.oil.level.in.the.reservoir..Do.
not.allow.oil.level.to.be.lower.than.the.reservoir..
b.. Quickly.attach.the.loaded.valve.plate.(16).(before.the.oil.runs.
out.past.the.diaphragms).with.socket.head.screws.(41),.but.
do.not.tighten.completely..Leave.a.gap.between.the.valve.
plate.and.the.cylinder.housing..Turn.the.shaft.-3.turns.to.
finish.forcing.out.air.behind.the.diaphragms..The.hydraulic.
cells.are.now.primed..Now.finish.tightening.the.valve.plate.
with.the.two.socket.head.screws.and.add.pump.manifold..
c.. Wipe.excess.oil.from.around.the.pump.head.
d.. Check.that.the.oil.level.is.1.inch.(5.mm).from.the.top.of.the.
fill.port.
e.. Replace.the.oil.fill.cap.and.complete.installation..
Method #2 (head pressure greater than 2 psi)
This. simple. and. clean. method. of. priming. the. Hydra-cells.
requires.an.inlet.head.pressure.of.at.least.5.feet.(1.5.m).or..psi.
(.14.bar)..The.pressure.source.is.required.to.hold.the.diaphragms.
back.while.the.piston.moves.so.as.to.force.out.the.air.
Completely assemble
.the.pump.and.fill.the.reservoir.with.the.
appropriate.Hydra-oil.to.the.fill.port..
a..
When tank head pressure is being used to prime
,.install.
the.pump.back.into.the.system.and.connect.the.tank.supply.
line.to.pump.inlet..Pump.discharge.line.may.be.connected.
at.this.time,.but.end.of.line.must.be.open.to.allow.air.to.pass.
out..
b.. Slowly.turn.the.pump.shaft.by.hand.and.watch.for.bubbles.
exiting.the.oil.reservoir.fill.opening..This.will.take.several.
rotations;.when.no.more.bubbles.come.out.and.the.reservoir.
level.has.dropped.about.1”.(5.mm),.the.hydraulic.cells.are.
primed.
c.. Replace.the.oil.fill.cap.and.complete.installation.
d..
When compressed air is being used to prime
,.insert.a.
clean.air.hose.to.the.pump.inlet.and.restrict.the.pump.outlet..
Turn.the.shaft.a.quarter.turn.and.then.apply.air.pressure.into.
the.manifold.to.put.pressure.on.the.diaphragms..This.will.
force.air.out.from.inside.the.pistons.and.you.will.see.bubbles.
at.the.reservoir.opening..Repeat.for.several.rotations.until.
no.more.air.bubbles.come.out.and.the.reservoir.level.has.
dropped. about. 1”. (5. mm).. The. hydraulic. cells. are. now.
primed.
e.. Replace.the.oil.fill.cap.and.complete.installation.
6. Reinstall Valve Plate (18),
Manifold (7), and Manifold
Support (43)
a...Reinstall. the. valve. plate. (18),. with. the. valve. assemblies.
installed.as.outlined.above,.onto.the.cylinder.casting..Use.
the.three.socket-head.capscrews.(39).with.O-rings.(48).to.
fasten.the.valve.plate.to.the.cylinder.casting..Verify.that.the.
valve.assemblies.are.still.in.place.
b...Reinstall.the.O-rings.(8,.9,.10).between.the.valve.plate.and.
manifold..Use.petroleum.jelly.or.lubricating.gel.to.hold.them.
in.place.
c... With. the. manifold. support. and. manifold. nested. together,.
and.the.centerbolt.(1).and.washer.().in.place.through.the.
center.hole,.locate.the.drain.plug.(4).at.the.bottom.and.hold.
the.manifold.and.support.against.the.valve.plate..Tighten.
the.centerbolt.by.hand.
d...Insert.all.bolts.(5),.washers.(6),.and.nuts.(31).loosely..Align.
the.outer.surfaces.of.the.valve.plate,.manifold,.and.manifold.
support,.and.torque.the.centerbolt.to.45.ft-lbs.(60.N-m).
e...Alternately.tighten.opposite.bolts.(5).until.all.are.secured..
Torque.to.45.ft-lbs.(60.N-m).
H/G-25-SD Service (Fluid End)