PRODUCT INFORMATION
INDEX
DATE
Dep. 2
IC-C-D-25-006e B
January 2015
DESCRIPTION OF A CRANKCASE GAS
RECIRCULATION SYSTEM
2/5
Fig.1: CGR on gas in-line engine FGLD/SFGLD.
Fig 2: CGR on gas V-engine FGLD/SFGLD.
Fig 3: CGR on HGM240 engine
Fig 4: CGR on HGM 420/560 engine
2.1. Crankcase
The crankcase or oil sump is an important component of the engine, which little attention is often paid to. In
addition to collecting, storing and recirculating oil that has lubricated and cooled the engine, the crankcase also
accumulates the gases leaking from the engine's combustion chambers through small interstices between the
rings and liners of each cylinder.
The amount of gas entering the crankcase will depend on the wear condition of the a.m. parts.
Due to crankshaft rotation and oil removal from different places in the engine, an undetermined quantity of oil
drops are carried by the blow-by gas flow.
The crankcase gas pressure indicates the status of balance between the amount of blow-by gases removed from
the crankcase through the exhaust system and the quantity generated during the engine operation.
By analysing the crankcase pressure over time, it is possible to anticipate any failure that would offset the said
balance in one direction or another, notably wear of piston rings, filter clogging, blocked pipes, etc.
5
4
3
1
6
2
70
6 0
4 0
0
° C
50
32
1 60
° F
1 40
1 20
90
70
5 0
9 0
°C
120
11 0
10 0
7
1 20
50
32
°C
7 0
160
°F
6 0
1 40
12 0
40
0
90
0
3
2
1
B ARS
6
5
4
50
7 0
9 0
°C
1 10
1 00
6
5
2
1
6
3
4
2.3.20
O&M_2.002211.810_A_10_2016
