Honda Marine BF25A Owner's Manual page 68

SERVICING YOUR OUTBOARD MOTOR
6. Install the spark plugs carefully,
by hand, to avoid cross-threading.
7.
After each spark plug seats, tighten
with a spark plug wrench supplied
in the tool kit to compress the
sealing washer.
If reinstalling the used spark plugs,
tighten
1/8
-
1/4 turn after the
spark plugs seat.
If reinstalling new spark plugs,
tighten 1/2 turn after the spark
plugs seat.
Loose spark plugs can overheat
and damage the engine.
Overtightening the spark plugs
can damage the threads in the
cylinder head.
8. Attach the spark plug caps.
9.
Install and lock the engine cover.
66