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10
MS 311, MS 391
3.3
Chain Lubrication
In the event of trouble with the
chain lubrication system, check and
rectify other sources of faults
before disassembling the oil pump.
.
Condition
Cause
Remedy
Chain receives no oil
Oil tank empty
Fill up with oil and check setting of
oil pump if necessary
Oil inlet hole in guide bar is blocked Clean oil inlet hole
Intake hose or pickup body clogged
or intake hose ruptured
Fit new intake hose and pickup
body
Valve in oil tank blocked
Clean or replace valve
Teeth on worm worn
Install new worm
Worm drive spring broken
Install new worm
Oil pump damaged or worn
Install new oil pump
Machine losing chain oil
Oil pump body damaged
Install new oil pump
Oil pump damaged or worn
Install new oil pump
Oil intake hose connection
damaged
Install new oil intake hose
Oil pump delivers insufficient oil
Oil pump worn
Install new oil pump
Worm drive spring not engaged in
clutch drum
Engage drive spring in notch in
clutch drum
Oil pump delivery rate set too low
Adjust oil pump
(only on version with adjustable oil
pump)