Inspection And Replacement Of Spark Plugs - Rotax 914 Series Maintenance Manual

6.2)

Inspection and replacement of spark plugs

See Fig. 39.
Because of the differing thermal load, particular spark plugs have been specified
for each engine type.
In numerous tests the best possible heat range has been determined to make
sure that the spark plug will burn off deposits but will not overheat.
■ CAUTION:
Ensure that the following spark plugs corresponding to engine type are
employed and that the correct spark plug socket is used.
Engine
914 Series
Electrode gap:
◆ NOTE:
- Inspect all spark plugs for mechanical damage.
- Check heat range and adjust electrode gap correspondingly.
■ CAUTION:
Before every installation, the spark plug thread and the spark plug seat at the
cylinder head should be cleaned (e.g. to remove residue of heat conduction
compound) Apply small amount of heat conduction compound to spark plug
thread and tighten spark plug to 20 Nm (177 in.lb) on the cold engine.
Heat conduction compound, see 05-00-00 sec. 2.5.
▲ WARNING: Rinse off with water in the case of contact with eyes or skin. May
Effectivity: 914 Series
Edition 1 / Rev. 0
MAINTENANCE MANUAL
Use of incorrect spark plugs can result in ignition problems and
pre-ignition
See 05-50-00 sect. 2.11.
Part No.
897257
New
0.7 - 0.8 mm (0.027 - 0.031 in )
If cold start problems are encountered, the electrode gap may
be reduced to 0.5 mm (0.020 in)
Heat conduction compound at the ground electrode (1) or
the head area (2) can lead to ignition problems. Apply heat
conduction compound sparingly and do not cover the first
three thread coils.
1
2
be harmful if swallowed.
BRP-Rotax
and consequent
Designation
ND X27EPR-U9
00086
engine damage.
Size of socket
12 mm (0.47 in)
Wear limit
0.9 mm (0.035 in)
Fig. 39
12-00-00
page 44
May. 01/07