O.S. Engines 18TZ(S)-T - Manual (Page 29)

Unstable idle
Unsuitable glowplug Use suggested glowplug in the instructions.
Unsuitable fuel Do not use extremely high nitro or low oil fuel.
Add suitable load. Extremely light flywheel
Install silencer securely. Silencer is disconnected or has play
Not reaching expected peak r.p.m.
Insufficient warming up or running-in.
Set the needle only after warming up.
Complete running-in.
Silencer or manifold is not securely connected
or disconnected.
Replace seal ring.
Check the connections and secure them.
Fuel tubing from tank to is split or broken. Replace the tubing.
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