Subject: Spark Plugs, Tightening Torque
Vehicles: All vehicles with petrol engines except MONTEREY and CAMPO
Examinations have indicated the necessity of increasing the tightening torque for spark plugs on all OHC/DOHC petrol engines (aluminium cylinder head) from the previous 20 Nm/15lbf.ft. to 25 Nm/18Ibf.ft. This measure applies retrospectively for the above-named engines.
For all engines, observe the following tightening torques for spark plugs during repair or inspection operations:
All OHC/DOHC engines (aluminium cylinder head) - 25 Nm/18 Ibf. ft.
All OHV/CIH engines (grey cast iron cylinder head) - 40 Nm/29.5 lbf. ft.
This modification is either already included in or will be gradually introduced into the Service literature.