Keiser Keiser 300, Parts And Maintenance Manual

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7
PROBLEM: Pressure changes without valves being actuated.
Service the Valves (see pg. 9)
AIR HOSES AND FITTINGS
All K300 machines use polyethylene tubing and “Compress-align” fittings to connect the
various pneumatic components within the machine.
If an air leak is suspected, first listen closely to the air hose connections. Leaks will
make a hissing noise. Very slight leaks may not be loud enough to hear. These may be
detected by dabbing soapy water on the suspected leak. Escaping air will make bubbles.
If the leak is at a fitting, first tighten the nut about one-quarter (1/4) of a turn. Test the
connection again. If the fitting still leaks, the nut must be replaced. In most cases the air
hose should be long enough to allow this; if not, order a new air hose from KEISER.
To install a new nut:
TOOLS REQUIRED: adjustable wrench and a sharp knife
1. Cut the tubing as close as possible to the nut. The cut must be clean and square.
2. Slip a new nut over the tubing.
3. Insert the tubing into the fitting all the way to the shoulder inside the fitting (see the
cutaway illustration).
4. Hold the tubing in the fitting and slide the nut down onto the fitting. Tighten the nut
as tight as possible with the fingers, then another one full turn with a wrench.
If reinstalling an air hose, tighten the nut finger-tight, plus one-quarter (1/4) turn. This
will allow the nut to be used three more times before it must be replaced.