Spark Plug - VESPA LX 4T USA Workshop Manual

LX 4T USA

Spark plug

The central electrode of the above spark plug is treated with silicone oil that acts as an antioxidant
agent. If the silicone oil is in excess, crystals tend to form and, by causing hot fire points to preignition
phenomena, tend to reduce the spark plug performance. This results in difficulties for vehicles to reach
the maximum speed and anomalous noises.
If the above situation should occur, replace the spark plug before performing any other intervention.
Before installing the new spark plug, blow with air to remove the silicone oil in excess.
Direct the jet of compressed air into the round groove between the threaded metal part and the ceramic
part of the inner electrode while turning the spark plug to allow removal of the oil in excess.
Detach the spark plug cap and then remove the
spark plug.
- Carefully examine the spark plug, and replace it
if the insulator is damaged or chipped.
- With the aid of a feeler gauge, measure the spark
gap and, if necessary, adjust by bending outer
electrode with care.
- Ensure the sealing washer is in good conditions.
- Refit the spark plug by engaging the thread man-
ually and then tightening it to the prescribed torque
using the box-spanner provided.
Characteristic
Electrode gap
0.7 ÷ 0.8 mm
Spark plug
NGK CR 8EB
Alternative spark plug
DENSO U24ESR-NB
Locking torques (N*m)
Spark plug
10 ÷ 15 Nm
Hub oil
Maintenance
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