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7. TROUBLESHOOTING
Although Tuthill Vacuum & Blower Systems blowers are well designed and manufactured, problems may
occur due to normal wear and the need for readjustment. The chart below lists symptoms that may occur
along with probable causes and remedies.
SYMPTOM
PROBABLE CAUSE
REMEDIES
Loss of oil
Gear housing not tightened
properly
Tighten gear housing bolts.
Lip seal failure
Disassemble and replace lip seal.
Insufficient sealant
Remove gear housing and replace sealant.
Excessive
bearing or
gear wear
Improper lubrication
Correct oil level. Replace dirty oil. See the
Lubrication
section.
Excessive belt tension
Check belt manufacturer’s specifications for tension and adjust accordingly.
Lack of
volume
Slipping belts
Check belt manufacturer’s specifications for tension and adjust accordingly.
Worn lobe clearances
Check for proper clearances.
Speed too low
Increase blower speed within limits.
Obstruction in piping
Check system to assure an open flow path.
Knocking
Unit out of time
Re-time.
Distortion due to improper
mounting or pipe strains
Check mounting alignment and relieve pipe strains.
Excessive pressure
differential
Reduce to manufacturer’s recommended pressure. Examine relief valve and reset if
necessary.
Worn gears
Replace timing gears. See the
Disassembly
section.
Excessive
operating
temperature
Excessive pressure
differential
Reduce pressure across blower.
Rotor end or
tip drag
Insufficient assembled
clearances
Correct clearances.
Case or frame distortion
Check mounting and pipe strain.
Excessive operating
pressure
Reduce pressure differential.
Excessive operating
temperature
Reduce pressure differential or reduce inlet temperature.
Vibration
Belt misalignment
Check carefully, realign if necessary.
Lobes rubbing
Check cylinder for hot spots, then check for lobe contact at these points. Correct
clearances.
Worn bearings or gears
Check condition of gears and bearings; replace if necessary.
Unbalanced or rubbing lobes Possible buildup on casing or lobes, or inside lobes. Remove buildup and restore
clearances.
Driver or blower loose
Check mounting and tighten if necessary.
Piping resonance
Check pipe supports, check resonance of nearby equipment, check foundation.
Blower rotors out of time
Remove blower and check timing.
