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Service Manual – SW5500, FLOORTEC R 985
29 - Engine System, LPG
Engine Spark Plug Check/Replacement
For the type of spark plug to be used, see
WARNING: A wrong spark plug can damage
the engine.
1
Drive the machine on a level floor.
2 Turn the ignition key to “0”, then engage the
parking brake
3 Open the engine compartment hood with the
handle and fasten it with the support rod
4 Lift and remove the machine right side panel,
disengaging it from the upper and lower
fasteners
5 Disconnect the spark plug cap (A) and remove
dirt around the spark plug (B)
6 Remove the spark plug with a suitable wrench
(C)
7 Check the spark plug Replace it if it is
damaged, dirty, if the sealing washer (D) is
damaged or if the electrode is worn
8 Measure the distance between the spark plug
electrodes with a feeler gauge Correct the
distance by bending carefully the side electrode
(E) The distance between the electrodes must be
of 0 70 - 0 80 mm
9 Install the spark plug manually with great care,
to avoid tightening it improperly
10 Once the spark plug is in place, tighten it with a
proper wrench to press the sealing washer
11 When a new spark plug is installed, tighten 1/2
turn once the spark plug is in place to press the
washer
12 When the original spark plug is reinstalled,
tighten 1/8 - 1/4 turn once the spark plug is in
place to press the washer
WARNING: A loose spark plug can overheat
and damage the engine. Do
not overtighten, otherwise the
threads in the cylinder head can
be damaged.
13 Connect the spark plug cap
B
A
C
D
E
0,7 - 0,8 mm
E
C
A
B
D
Figure 8: