17
H5-991-406A
H/G-25-SD Service (Hydraulic End)
i... After.all.three.nuts.(31).are.tightened,.insert.a.capscrew.(6),.
with.washer.(6),.into.the.unused.threaded.hole.in.the.cylinder.
casting..Then.remove.the.assembly.stud,.washer,.and.nut.
that.are.opposite.the.capscrew.just.added,.and.replace.them.
with.another.capscrew.and.washer..Finally,.remove.the.other.
two.assembly.studs,.which.should.be.on.opposite.sides.of.
the.pump.housing.from.each.other,.and.replace.them.with.
capscrews.and.washers..Torque.the.capscrews.to.5.ft-lbs.
(34.N-m).
j... Turn.the.shaft.again.to.check.its.alignment.
5. Replace Shaft Seals
a...Apply.a.thin.film.of.grease.on.the.seal.protector.tool.(from.
the.Wanner.Tool.Kit)..Slide.both.seals.onto.the.tool,.with.the.
spring.side.of.the.seals.toward.the.open.end.of.the.tool.
.
Apply.a.heavier.coat.of.grease.between.the.seals.and.press.
them.together..Wipe.off.any.excess.grease.that.may.squeeze.
out.onto.the.outside.of.the.seals.
b...Apply.a.coating.of.Loctite
h
.High-Performance.Pipe.Sealant.
with.PTFE,.or.a.comparable.product,.to.the.outer.surface.
of.both.seals.and.the.inside.surface.of.the.opening.in.the.
pump.housing.where.the.seals.will.rest.
c... Apply. a. light. film. of. grease. to. the. drive. shaft.. Slide. the.
seal.protector.tool.(with.the.two.seals).over.the.end.of.the.
shaft.
d...Slide.the.seal.inserter.tool.(from.the.Wanner.Tool.Kit).over.
the. seal. protector. tool,. and. press. the. seals. completely.
into.place..Tap.the.tool.with.a.soft.mallet.to.firmly.seat.the.
seals.
6. Adjust Camshaft Endplay
a...If.the.three.set.screws.(4).are.in.the.cylinder.housing.(5),.
remove.and.clean.them.
b...Insert.the.centerbolt.(1).into.the.hole.in.the.center.of.the.
cylinder.housing..Turn.it.in.to.move.the.bearing.adjusting.
plate.(61).and.cup.tight.against.the.bearing.cone.
c... Back.out.the.centerbolt.
two
.full.turns,.then.turn.it.back.in.
again.until.it.is.tight.against.the.adjusting.plate.(61).to.ensure.
the.proper.fit.
d...Back.out.the.centerbolt.
exactly 1/4
.of.a.turn.
e...With.a.plastic.mallet.(or.a.regular.mallet.and.wooden.board).
to. prevent. damage. to. the. shaft,. rap. the. end. of. the. shaft.
three. or. four. times.. This. will. provide. about. .006. in.. (0.15.
mm).endplay.in.the.shaft.
f... Apply.removable.threadlocker.to.the.threads.of.the.three.
cleaned.set.screws.(4),.then.screw.them.into.the.cylinder.
casting.until.they.contact.the.bearing.adjusting.plate.(61).
g...Remove.the.centerbolt.(1).
7. Install Plungers
Note: If the plungers (23) have been removed from the
valve plungers (54), do not reuse them. Install new ones
instead.
a...Rotate.the.pump.shaft.so.the.piston.is.in.the.top-dead-center.
position.
b...With.the.nut.turned.back.toward.the.hex.head.of.the.plunger.
guide.lifter,.slide.the.plunger.guide.sleeve.over.the.large.
thread.of.the.lifter.(both.the.lifter.and.guide.are.included.in.
the.Wanner.Tool.Kit).
c... Place.a.plunger.on.the.exposed.screw.end.of.the.plunger.
guide.lifter..The.larger-diameter.side.of.the.plunger.should.
face.the.tool.
d...Screw.the.guide.(with.the.plunger).into.the.valve.plunger.
(54).until.tight.
e...Hold.the.plunger.guide.sleeve.with.a.1-in..(6-mm).open-
end.wrench..Turn.the.hex.nut.down.with.a.3/4-in..(19.mm).
open-end.wrench.to.force.the.plunger.to.seat.on.the.valve.
plunger..This.is.a.press-fit.—.when.installed,.the.plunger.
should.be.tight.against.the.shoulder.of.the.valve.plunger.
.
Note: Do not remove the plunger guide until the
diaphragm is installed (see below).
f... Install. the. diaphragm. as. outlined. below,. then. repeat. the.
procedure.for.the.other.two.plungers.and.diaphragms.
8. Reinstall Diaphragms
a...With. the. plunger. guide. tool. still. screwed. into. the. valve.
plunger.(54),.pull.the.valve.plunger.up.until.the.cross-holes.
in.the.valve.plunger.are.exposed.
b...Insert.the.plunger.holder.(from.the.Wanner.Tool.Kit),.or.a.
similar.dowel-type.object,.through.the.holes—.to.hold.the.
plunger.(3).away.from.the.cylinder.housing,.and.to.keep.
the.valve.plunger.from.turning.when.the.diaphragm.is.being.
installed.
c... Place.the.diaphragm.().onto.the.plunger.(3),.ridge-side.
out.
d...Center.the.diaphragm.follower.(1).on.the.diaphragm.
e...Place.the.O-ring.(0).onto.the.follower.screw.(19).
f... Apply.a.small.amount.of.threadlocker.to.the.threads.of.the.
follower.screw.
g...Insert.the.follower.screw.(with.O-ring).through.the.diaphragm.
follower.(1).and.diaphragm.(),.and.screw.it.into.the.valve.
plunger.(54).
h...Hold.the.plunger.holder,.and.torque.the.follower.screw.to.18.
in.-lbs.(.0.N-m).
i... Repeat.the.above.procedure.for.the.plungers.and.diaphragms.
of.the.other.two.cylinders.
j... Fill. the. reservoir. with. fresh. oil. and. prime. the. pump,. as.
outlined.in.the.Fluid.End.Service.Section.
9. Reassemble Pump Head
Reassemble.the.pump.head.as.outlined.in.the.Fluid.End.Service.
Section.