238
POWERHEAD
GENERAL
GENERAL
Cylinder Compression Testing
Start and run outboard until it achieves operating
temperature, then shut OFF.
Disconnect crankshaft position sensor (CPS) con-
nector. Remove all spark plugs.
Advance throttle linkage to WOT.
Install compression tester’s hose attachment into
spark plug hole (14 mm threads).
While cranking outboard with starter, note maxi-
mum pressure reading on gauge. Repeat proce-
dure for each cylinder.
If engine shows a variation greater than 15 psi
(100 kPa) between cylinders, check for:
• damaged cylinder head
• damaged pistons
• broken or stuck piston rings
• scored cylinder walls
Return throttle to idle position and reconnect CPS
connector. Replace spark plugs.
Refer to Spark Plug Indexing on p. 160.
Retaining Ring Pliers
Retaining Ring Pliers DRC2523