WÄRTSILÄ VASA 6L32, Instruction Manual

Page: 214 / 394

Testing tool of cylinder tightness
12.A.1.4 Measurement
1 Connect air to the tool with a pressure of 6-7 bar
(= normal
working air pressure). Open the valve on the tool and record the pressure.
2 Close the valve.
Measure the time in seconds it takes for the
pressure dropping to 0.5 bar.
••••
If the pressure from the beginning was 6 bar and it takes more
than 10 sec. for the pressure to drop to 0.5 bar, the result is
acceptable.
••••
If the pressure drops directly to 0 bar, it is possible that one or
more valves are sticking or the valve(s) are burnt.
A sticking valve can be found from the immobility of the valve
when the engine is turned.
A burnt valve can normally be seen from the exhaust tempera-
ture. If the valve clearance is zero that would also cause an direct
pressure drop.
••••
Carbon particles trapped between the valve and the seat when
the engine is stopped could also prevent the valve to close properly
thus causing a direct pressure drop. If that is suspected, the
engine should be run for a few minutes and after that a new check
of the same cylinder.
•••• If a blow-by between the cylinder liner and piston is suspected e.g.
from fast fouling of filters or high crankcase pressure, it is best to
take readings of the complete engine and make a comparison.
For example: From a six cyl. engine you get a serial: 12, 17, 15,
0 10
5
2
1
3
4
6
7
8
9
0 10
5
2
1
3
4
6
7
8
9
0 10
5
2
1
3
4
6
7
8
9
VASA 32, 848020
WÄRTSILÄ 20, 848020
WÄRTSILÄ 32, 800064
WÄRTSILÄ 34SG, 848020 WÄRTSILÄ 32DF, 848020
848 052
848 052
848 061
Fig A-1
321260200142
Appendix A Testing of cylinder tightness 32-200142
A - 2 Wärtsilä 20/32/34