Sea-doo 2003 GTI LE RFI, Shop Manual

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Section 07 ENGINE MANAGEMENT (DI)
Subsection 03 (COMPONENT INSPECTION AND ADJUSTMENT)
07-03-38
SMR2003_024 _07_03A.FM
With safety lanyard INSTALLED on its switch :
Measure resistance. There should be continuity.
Otherwise replace DESS switch.
If switch tests good in both checks, do the follow-
ing.
Disconnect the connector on electrical box.
Using a voltmeter, perform the following tests:
Connect test probes to the small RED wire on the
starter solenoid and on the RED/PURPLE wire from
the cut-off relay. Reading should be 0 V. Otherwise,
replace the cut-off relay.
Keeping the test probes on the same wires, con-
nect a jumper wire between the BLACK/PURPLE
wire from the cut-off relay and the battery ground.
Measure voltage. Reading should be 12 V. Other-
wise, check wiring and if it is good, replace the cut-
off relay.
If there is no current supply to the electrical com-
ponents while the DESS switch and the cut-off re-
lay test good, check the wiring harness. If it tests
good, the MPEM could be suspected. Try a new
one.
SPARK PLUGS
Disassembly
First unscrew the spark plug one turn.
Clean the spark plug and cylinder head with com-
pressed air then completely unscrew.
Heat Range
The proper heat range of the spark plugs is deter-
mined by the spark plugs ability to dissipate the
heat generated by combustion.
The longer the heat path between the electrode tip
to the plug shell, the hotter the spark plug operat-
ing temperature will be — and conversely, the
shorter the heat path, the colder the operating tem-
perature will be.
A “cold” type plug has a relatively short insulator
nose and transfers heat very rapidly into the cylin-
der head.
Such a plug is used in heavy duty or continuous
high speed operation to avoid overheating.
The “hot” type plug has a longer insulator nose
and transfers heat more slowly away from its firing
end. It runs hotter and burns off combustion de-
posits which might tend to foul the plug during
prolonged idle or low speed operation.
1. Cold
2. Hot
CAUTION: Severe engine damage might occur
if a wrong heat range plug is used.
A too “hot” plug will result in overheating and pre-
ignition, etc.
A too “cold” plug will result in fouling or may cre-
ate carbon build up which can heat up red-hot and
cause pre-ignition or detonation.
Fouling
Fouling of the spark plug is indicated by irregular
running of the engine, decreased engine speed
due to misfiring, reduced performance, and in-
creased fuel consumption. This is due to a loss of
compression. Other possible causes are: pro-
longed idling, or running on a too rich mixture or
incorrect fuel. The plug face of a fouled spark plug
has either a dry coating of soot or an oily, glossy
coating given by an excess either of oil or of oil
with soot. Such coatings form a conductive con-
nection between the center electrode and ground.
Spark Plug Installation
Prior to installation make sure that contact surfac-
es of the cylinder head and spark plug are free of
grime.
1. Using a wire feeler gauge, set electrode gap ac-
cording to the following chart.
2. Apply anti-seize lubricant over the spark plug
threads to prevent possible seizure.
A00E09A
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