Technical Information 08.2005
Page 17
TI_08_2005_11_01_02.fm
5.5
Test the compression pressure
In order to discharge the ignition voltage,
the ZAT 3 5910 850 4520 ignition system tester
must be mounted – high voltage shock hazard!
.
Remove the ignition system tester from the
spark plug, and screw out the spark plug.
.
Screw in compression tester 5910 850 2000 (
1
)
into the sparkplug hole.
.
Connect the spark plug boot to the high voltage
terminal (
1
).
.
Affix the ground terminal (
2
) to the muffler.
.
Set the knob (
3
) for the spark gap to
approx. 2 mm.
While using the ZAT 3, hold it only by the handle (
4
)
or position it in a safe place. Fingers and other body
parts must be at least 1 cm away from the spark
window, high-voltage terminal, ground connection
and ground terminal.
.
Pull the rewind starter quickly and forcefully
(min. 1,000 rpm) as when starting.
.
Read the compression –
the target is 7.5 ... 8.5 bar
If the compression is under 7.5 bar
.
Check valve clearance, set if necessary and
recheck the compression
If the compression is still under 7.5 bar
.
Check the cylinder, valve seat, piston and piston
rings for scoring and damage.