Test Procedures; Cylinder Compression Test - BRP Johnson J30TEL4SUA 2007 Service Manual

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TEST PROCEDURES

TEST PROCEDURES

Cylinder Compression Test

Start the engine. Allow the engine to warm up,
then shut off the engine.
Remove the engine side covers.
Remove all spark plugs.
Install a compression gauge and adapter into the
plug hole.
1. Spark plug hole
R C M
EMOTE ONTROL
Disconnect the throttle cable from the throttle
lever. Hold the throttle lever in wide open position.
T H M
ILLER ANDLE ODELS
Disconnect the throttle limiter rod from the throttle
drum. Hold the throttle control grip in the wide
open position.
118
ODELS
Disconnect the safety lanyard from the
emergency stop switch prior to cranking
the engine. This will prevent any residual
fuel from the cylinders from being ignited
by a spark from the spark plug cap.
While cranking the engine, note the maximum
pressure reading on the gauge for each cylinder.
IMPORTANT:
only guidelines, not absolute service limits.
Cylinder Compression Test
1
Standard
Maximum difference
between cylinders
Low compression pressure can indicate one or
more of the following:
•
Excessively worn cylinder wall
001377
•
Worn piston
•
Worn or stuck piston rings
•
Poor seating of valves
•
Ruptured or damaged cylinder head gasket
Install all parts that were removed.
WARNING
The values that are shown are
145 to 203 psi
(1000 to 1400 kPa)
14 psi (100 kPa)