Release 00 - 02/2008
Engine WBE 0701-WBE 0704
pag. 35
Service manual
13. ENGINE BLOCK - External operations
13.1. Checking the compression
1 - Remove the cap (1) and take out the spark
plug (2).
2 - anually set the piston to the TDC (Top Dead
Centre) of the compression stroke so that both
valves are closed.
3 - Screw the terminal of the compression te-
sting tool (3) into the spark plug hole and connect
the supply pipe to a compressed air socket with a
pressure of approximately 4 bar (58 psi).
4 - On opening the air tap (4), the manometer
gauge on the engine side should position itself in
the green zone and remain there for about 30 se-
conds. If the gauge falls rapidly it means that the
compression is poor
NOTE: Lack of compression could be due
to:
- incorrect valve clearance [ 13.2];
- cylinder head loose or cylinder head gasket worn
[ 13.3].
- lack of seal in the valves [ 13.4];
- piston rings worn [ 13.3].
5 - Ret the spark plug (2) and close it to the indi-
cated couple.
2
1
3
4