INSTALLATION OF KNOCK SENSOR
Spark Plugs
1.
Inspect each plug individually for badly worn
electrodes, glazed, broken or blistered porcelain
and replace where necessary.
IMPORTANT: If installing a new knock sensor, be
sure to replace it with an identical part. Knock
sensors are very sensitive and designed for each
specific application.
2. Inspecteachsparkplugformakeandheatrange.
All plugs must be the same make and number
and heat range. Refer to “Specifications” for
spark plug numbers.
IMPORTANT: It is very important that the knock
sensor be torqued to the exact specification. In-
correct torquing will result in unsatisfactory per-
formance. DO NOT use sealer on threads.
3. Adjust spark plug gaps with a round feeler gauge.
Refer to “Specifications” for proper spark plug
gap.
1.
Install knock sensor in engine block. Torque to
12-16 lb. ft. (16.3-21.7 N·m).
a
b
c
f
d
a
e
72734
a - Porcelain Insulator
b - Insulator Cracks Often At This Point
c - Shell
73756
d - Proper Gap
e - Side Electrode (Bend To Adjust Gap)
a - Knock Sensor
f - Center Electrode (File When Adjusting Gap - DO NOT
Bend)
2.
Connect electrical connector to knock sensor.
4.
Clean spark plug seating area. Do not use gas-
kets on taper seat plugs. Install spark plugs and
torque to specifications. Where used, gasket
must be fully compressed to complete heat trans-
fer and provide a gas- tight seal in cylinder. For
this reason, as well as the necessity of maintain-
ing correct plug gap, correct torque is very impor-
tant during installation.
IMPORTANT: Tapered seat spark plugs are not in-
terchangeable with non-tapered (with gasket)
spark plugs.
Index
4B-22 - IGNITION SYSTEM
90-823224--2 796
| Categories | Mercury MerCruiser Manuals |
|---|---|
| Tags | Mercury MerCruiser 454 CID, Mercury MerCruiser 502 CID |
| Model Year | 1993, 1994, 1995, 1996, 1997 |
| Download File |
|
| Document File Type | |
| Copyright | Attribution Non-commercial |
(4 votes, average: 4.5 out of 5)
Marine readers have rated 1993 1997 Mercury-MerCruiser GM V8 454 CID 7.4L and 502 CID 8.2L Marine Engines Service Manual Number 16 4.5 out of 5.0 based on 4 product reviews. Hugely helpful service manual! Perfect. Thank you!
Manuals are all Important for Technician
This book is invaluable if you do your own repairs. Great book.
Could not find a copy until a search brought me here.
Excellent print.
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