Stihl RM 650 V Instruction Manual page 71

– RM 650 VS, RM 655 RS, RM 655 VS,
RM 655 YS: Throttle cable disengaged
or defective (e.g. kinked).
Remedy:
– RM 650 T, RM 650 V, RM 655 V:
Press motorstop lever to handlebar and
hold. ( 10.2)
– RM 650 VS, RM 655 RS, RM 655 VS,
RM 655 YS: Set throttle lever to Choke
or Start position. ( 13.5)
– RM 650 VE: Charge or replace battery.
( 9.5)
– Top up fuel; clean fuel line. 
– Always use fresh, good quality fuel,
unleaded petrol; clean carburettor. 
– Clean air filter. 
– Connect spark plug socket; check
connection between ignition lead and
socket. 
– Clean or replace spark plug; adjust
electrode gap. 
– Clean lawn mower housing. First
disconnect spark plug socket and, for
model RM 650 VE, also remove
battery. ( 9.5)
– RM 650 VS, RM 655 RS, RM 655 VS,
RM 655 YS: Attach or replace throttle
cable. 
Fault:
Starting problems or deteriorating engine
power
Possible cause:
– Lawn mower housing blocked.
– Mowing at an excessively low cutting
height or fast speed
– Water in fuel tank and carburettor;
carburettor blocked
– Contaminated fuel tank
– Dirty air filter
0478 111 9953 B - EN
– Dirty spark plug
Remedy:
– Clean law mower housing. First
disconnect spark plug socket and, for
model RM 650 VE , also remove the
battery. ( 9.5)
– Adapt cutting height and reduce
mowing speed
– Empty fuel tank, clean fuel line and
carburettor 
– Clean fuel tank 
– Clean/replace air filter @, 
– Clean spark plug 
Fault:
Engine overheating.
Possible cause:
– Oil level in engine too low.
– Cooling ribs dirty.
Remedy:
– Change engine oil. ( 8.6)
– Clean cooling ribs. ( 14.2)
Fault:
No drive when self-propulsion lever is
actuated.
Possible cause:
– RM 655 YS: Self-propulsion cable
incorrectly adjusted.
– Self-propulsion cable defective (e.g.
kinked).
– V-belt worn.
– Gearbox defective.
Remedy:
– RM 655 YS: Check cable adjustment.
( 14.11)
– Replace cable. 
– Replace V-belt. 
– Replace gearbox. 
Fault:
Speed control not functioning
Possible cause:
– Driving speed lever moved in wrong
direction.
– Cable disengaged or defective
(e.g. kinked).
Remedy:
– Move driving speed lever in the correct
direction. ( 13.9)
– Attach or replace cable. 
Fault:
Mowing channel blocked
Possible cause:
– Mowing blade is worn.
– Mowing grass which is too long or too
wet.
– RM 650 VS, RM 655 RS, RM 655 VS,
RM 655 YS: Engine speed is too low.
Remedy:
– Replace mowing blade. ( 14.4)
– Adapt cutting height and mowing speed
to mowing conditions. ( 12.), ( 9.4)
– RM 650 VS, RM 655 RS, RM 655 VS,
RM 655 YS: Set the throttle lever to the
Start position. ( 13.5)
Fault:
Poor cut, lawn turning yellow
Possible cause:
– Blade is blunt or worn.
– Mowing speed is too high in relation to
cutting height.
– RM 650 VS, RM 655 RS, RM 655 VS,
RM 655 YS: Engine speed is too low.
Remedy:
– Sharpen or replace blade ( 14.3),
( 14.4), 
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