Grinding, Rubbing, Knocking Noise - Life Fitness 8500 Service Manual

Life Fitness Model 8500, 9100, and 9500HR Cross-Trainers
Malfunction
Grinding, rubbing, knocking noises
when pedal levers rotate under
load.
2
Probable Cause
Pulleys misaligned.
Dirt build up in pedal tracks.
Rear roller wheels frozen.
Link cover contacting rear cover.
Excessive disk wobble.
Faulty intermediate shaft assembly.
Faulty pillow block.
Alternator.
Bearings at pivot points are out of
position or dirty.
Setscrews or crankarm bolt in
crankarm assembly are loose.
Small extension arm bolt loose.
Faulty link bearings.
Corrective Action
Loosen the pillow block bearings,
realign the pulleys, and retighten the
pillow block bearings.
Clean and remove dirt build up.
Clean and lubricate with non
detergent oil.
Reposition rear cover(s) or replace.
Check that the inner link cover
mounting screws are properly
installed.
Make sure no weld interference
occurs between the crankarm and
the disk cover.
Ensure that the crankshaft is flush
with the crankarm and check for
proper alignment. See How To.
Replace intermediate shaft assy.
Replace pillow blocks on crankshaft.
Relieve tension on alternator, spin
flywheel for smoothness. If
thumping occurs, faulty alternator.
Replace alternator.
Clean all sleeves in the linkage pivot
areas and lubricate with non
detergent oil.
Loosen setscrew and clamping
screw in crankarm assembly. Apply
®
blue Loctite (242) on screw threads.
Tighten setscrew first to set keyway,
then tighten clamping screw.
Crankarm bolt requires no Loctite.
Replace small extension arm kit.
Replace link assembly.