Cylinder Compression Test; Cylinder Head Inspection - TOHATSU BFT250A Service Manual

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CYLINDER COMPRESSION TEST

Set the remote control lever in the "N" (neutral) position.
Remove the engine cover and disconnect the ECM
connector A [1] and B [2].
Remove the spark plugs (page 3-17).
Install a compression gauge (EEPV303A: commercially
available) [1] in the No.1 plug hole.
Set the throttle in the full throttle position by pulling the
throttle arm [1] against the full throttle stopper [2] by
hand as shown.
Set the combination switch in the START position and
turn the starter motor until the maximum reading is
obtained. Measure the cylinder compression.
CYLINDER COMPRESSION (Pressure check at 200
-1
min (rpm) with wide open throttle):
1,450 – 1,690 kPa (15 – 17 kgf/cm
Check the compression on all cylinders.

CYLINDER HEAD INSPECTION

VALVE SPRING FREE LENGTH
Measure the free length of the valve springs.
STANDARD:
IN: 51.32 mm (2.020 in)
EX: 53.48 mm (2.106 in)
[2]
[1]
2
, 210 – 245 psi)
[1]
CYLINDER HEAD
[1]
[2]
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