TM 9-4940-342-14&P
CHAPTER 6
REPAIR OF STEAM CLEANER
6-1.
Plumbing Assembly
Repairs on plumbing assemblies require the same
procedures normally utilized on equal or similar
applications. All fittings shall be replaced with new
components, all pipe joints sealed with teflon tape
or pipe dope. No attempts shall be made to patch,
plug, solder or weld leaks nor shall fittings be
distorted or altered in any way for the purpose of
forced installation.
6-2.
Water Pump Repair (Refer to Fig C-9)
a. The following steps have been provided to
assist the operator in the normal care and
maintenance of the pumping system. Specifications
and procedures must be followed to assure
maximum pump operation and unit life.
CAUTION
Disconnect the power source before performing
any service on the pump.
(1) General care of the pump.
(a) Drain and refill the pump crankcase
with clean SAE 20 non-detergent oil after the first
100 hours of operation. Following the first 100
hours of operation, for best results, always change
the oil every 750 hours of operation.
(b) Keep all piping and mounting bolts
tight.
(c) Replace all worn parts promptly with
exact replacement parts.
(2) Care in freezing weather.
CAUTION
Precaution must be taken to avoid damage to the
pump from liquid allowed to freeze in the valve
chamber.
(a) Drain all connecting piping.
(b) Remove cap screw, clamp, valve cover
and valve disc and spring assemblies to drain the
valve chamber, when freezing temperatures are
expected. Remove top discharge valves or raise
them to be sure that no liquid is trapped under the
inner suction valves.
(3) Servicing the plunger packings.
(a) Release the valve chamber from the
pump case by removing the three cap screws using
a 9/16-inch wrench.
(b) Lift the chamber free of the cylinders.
Remove the cap screws, cup washers and plunger
packings (cups).
(c) Lift the cylinders from the pump case.
(d) Inspect the O-rings and umbrellas. If
either of these parts are damaged, they should be
replaced. A pocketknife can be used for easiest
removal of the umbrellas.
NOTE
Clean all parts thoroughly and replace worn parts
with exact replacement parts.
(e) Reassembling plunger packings, inspect
bottom gasket and replace if necessary.
NOTE
If it is necessary to replace one gasket at either top
or bottom of cylinders, then both top and bottom
gaskets should be replaced.
NOTE
For easier installation of the umbrella, immerse in
hot water for approximately two to three minutes to
soften.
(f) Fold the plastic umbrellas to insert them
through openings and over ends of crosshead rods.
(g) Press tops of umbrellas to place pilot
washers over ends of rods with groove up.
(h) Place O-rings and packing holders in
position on ends of crosshead rods.
(i) Place cylinders in position in the
mounting plate recess.
(j) Oil the plunger packings and place them
in the open end of the cylinders, with the bottom cup
down, top cup up. Use the thumb to press the
packings into each cylinder, firmly and squarely on
the plunger rod end.
(k) Turn the pump by hand to raise each
plunger rod to the top of the stroke, as needed.
(l) Place the cup washers with the ribbed
side against the plunger packing inside the cups of
the packing.
(m)Secure packing and washers to plunger
rods with cap screws, tightening them until the
washers and cups seat firmly on the plunger rods.
(n) Inspect top cylinder gaskets and replace
both if either shows a defect. Holding them in place
in the valve chamber by using a heavy oil or grease if
necessary.
(o) Return the valve chamber to position over
the
cylinder
making
sure
that
gaskets
and
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