Diagnose - BOMBARDIER DS 650 Shop Manual

Supply combustion chamber with air pressure.
1. Leak tester
2. Adequate adapter for spark plug hole
3. Air supply hose
Note the amount of leaking or percentage (de-
pending on tester).
LEAKAGE
PERCENTAGE
0% to 7% Excellent condition.
Fair condition; proceed with tuned
8% to 15%
up or adjustment.
Poor condition; engine will run and
16% to 30% performance might be down in
some cases.
Very poor condition, diagnose and
30% and higher
repair engine.
VMR2004_007_03_03A.FM
ENGINE CONDITION
Subsection 03 (LEAK TEST)

DIAGNOSE

Listen for air leaks:
– air escaping from spark plug means poor spark
plug tightness or defective spark plug gasket
– air escaping from intake means leaking intake
valve
– air escaping from exhaust means leaking exhaust
valve
– air/oil escaping from crankcase means damaged
gasket and/or loosened screws
(refer to CRANKSHAFT/BALANCER SHAFT)
– air bubbles out of radiator means leaking cylin-
der head gasket
– air/coolant escaping from cylinder/head means
damaged gasket(s) and/or loosened screws.
(refer to CYLINDER AND HEAD)
– air escaping into crankcase area means exces-
sively worn cylinder and/or broken piston rings.
NOTE: For all the check mentioned above see the
appropriate engine section to diagnose and repair
the engine.
INSTALLATION
NOTE: At reassembly, use the torque values and
Loctite products from the exploded views (refer to
particular engine sections).
For installation, reverse the preparation procedure.
Section 03 ENGINE
03-03-3