04 EXHAUST SYSTEM
Page EXHAUST SYSTEM - 4
Z001019/0_6_July 2008
SERVICE MANUAL MARINE ENGINES
01.02 ill.1
01.02 ill.2
04.01.02
Measurement of exhaust
backpressure
special tool No. VR00136/0
ill.1/pos.1
pressure gauge (0-1 bar)
ill.1/pos.3
intermediate sealing ring
ill.1/pos.4
pressure gauge connection
ill.1/pos.5
pressure hose
ill.1/pos.6
double union
ill.1/pos.7
sealing ring
ill.1/pos.9
screw-in adaptor
1
Disconnect plug for exhaust temperature switch (ill.2/
pos.5).
2
Dismantle high-riser temperature sensor, connect
plug to sensor again, and fix it temporary on the
engine.
3
Mount double union (ill.1/pos.6) with sealing ring
(ill.1/pos.7) instead of hi-riser temperature sensor.
4
For 6 cyl. engines only (with FORD ECU)
Screw in double union (ill.1/6) with sealing ring (ill.1/
7) into screw-in adaptor (ill.1/9) and mount screw-in
adaptor instead of hi-riser temperature sensor.
5
Mount seal ring (ill.1/pos.3) with pressure gauge
connection (ill.1/pos.4) onto pressure gauge (ill.1/
pos.1) Connect pressure gauge to one end of pressure
hose (ill.1/pos.5).
6
Connect the other end of pressure hose (ill.1/pos.5)
to double union (ill.1/pos.6).
MEASUREMENT:
Drive the boat under operating conditions (rated output at rated speed) and read off pressure
on pressure gauge.
RESULT:
With an exhaust pressure below 100 mbar at rated output of engine, the exhaust system
is dimentional correctly and represents the ideal status. (up to max. 200 mbar acceptable)
With an exhaust pressure exceeding 200 mbar at rated output of engine, tuning of exhaust
system is no more ideal. To avoid losses in efficiency, changes in the exhaust system should
be made (pipe diameter, pipe lengths, muffler etc.)
An exhaust pressure of 300 mbar at rated output of engine is no more acceptable.
ATTENTION:
Changes in the exhaust system (pipe diameter, pipe lengths, muffler etc.) absolutely required.
Considerable influence on output, fuel consumption and life of engine.
7
Assembly is done in reverse order:
1
2
10
6
7
8
9
3
4
5
7
9
1
3 4
5
6
ToC
