Nordson 25B - Excessive or Constant Air Leakage from Air Motor or Air Valve

© 2024 Nordson Corporation
1044131-06
5-3
Troubleshooting
Problem Possible Cause Corrective
2. Excessive or
constant air leakage
from air motor or air
valve
Worn seal in the upper or lower cylinder head
Remove the safety covers
from around the air motor.
Check for air leaking around
the connecting rod or around
the push rod. Replace any
leaking seals.
Worn O-rings on the air valve crankshaft or crankshaft end
bushing
Remove the safety covers
from around the air motor.
Check for air leaking around
the crankshaft or end
bushing. Replace the leaking
O-ring.
Ice forming in valve
Remove the safety covers
from around the air motor.
Check for air leaking from the
valve exhaust ports or ice on
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Allow the pump to idle as it
warms. If the leaking stops,
refer to Preventing Air Valve
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section.
Air valve poppet-seal washers, or piston worn or damaged
Remove the safety covers
from around the air motor.
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Make sure ice is not
preventing the valve spool
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from both ends of the air
valve, the washers sealing
the poppet or the piston seal
are leaking. Replace the
washers around the poppets.
If the problem continues,
inspect the piston.
Replace the piston if the seal
is worn or damaged. Refer to
25B Air Valve and Air Motor
Repair.
Damaged gaskets between the air valve and the upper
cylinder head
Remove the safety covers
from around the air motor.
If air leaks from between
the air valve and the upper
cylinder head, remove the
air valve and replace the
gaskets.
Continued...