KTM 690 LC4 2007, Repair Manual

Page: 42 / 95

5-9
1
2
Timing chain tensioner
! CAUTION !
I
F YOU DO NOT FOLLOW THESE INSTRUCTIONS
,
THE TIMING CHAIN WILL NOT BE
TENSIONED CORRECTLY AND WILL SKIP
,
RESULTING IN ENGINE DAMAGE
.
NOTE:
– The timing chain tensioner
1
operates with spring force and with oil
pressure. A stop system is used to ensure the right timing chain
tension in the engine starting phase, even if the oil pressure is
insufficient. The stop system prevents the piston
2
on the timing
chain tensioner from being retracted.
– In a dismounted state, the piston on the timing chain tensioner
extends completely.
– Fully depress the spring tensioner. This will require some effort
since the oil must be squeezed out. If the timing chain tensioner is
released it will extend completely again; it may not be mounted in
this state, since the locking mechanism will not function.
– Press down on the timing chain tensioner to ensure smooth
operation.
– To prepare the timing chain tensioner for installation, place 2
spacing washers or similar implements with a thickness of 2 - 2.5
mm next to the piston of the timing chain tensioner. This will ensure
that the piston cannot be completely retracted when the piston is
pressed down. If you release the piston, the stop system will lock,
the piston will protrude approx. 3 mm and stay in this position - this
position is required for refitting!
– If you press the timing chain tensioner again and it extends no more
than half way (preventing it from extending completely), the stop
system will lock and the timing chain tensioner can no longer be
pressed together - this position is necessary to ensure that the
timing chain is adequately tensioned, even if the oil pressure is low.