Norton Service Release Database N14

SERVICE RELEASE N14

NATURE OF RELEASE: Removing Cylinder Head in Frame MODELS AFFECTED: Al 1 Commando PARTS AFFECTED: Cylinder Head and Fittings DISTRIBUTION: Worldwide EXPLANATION: It is apparent that there is some confusion amongst dealers and owners where it is considered impossible to remove the cylinder head with the engine in the frame, without removal of the cylinder block at the same time. The cylinder head can be removed and re-fitted with very little difficulty by the following means   ACTION: Assuming all ancilliary equipment (gas tank, coil cluster, exhausts and mufflers, head torque stay, three rocker covers, rocker oil feed pipe and carburettors on manifolds) has been removed, slacken all rocker adjusters completely, remove five nuts below and five bolts above the cylinder head and separate tho cylinder head from the cylinder block - if necessary a light blow under the. exhaust ports on the head with a hide mallet will dislodge the head. All that now prevents the head from being lifted clear is the presence of the pushrods. A second operator is now required, the first to lift the hoad whilst the second lifts all four pushrods clear of the rocker arms which are then pivoted well clear of the valve stems allowing the pushrods to slide past into the rocker box portion of the hoad. Tho pushrods will lift sufficiently to clear the cylinder block whilst the head is lifted out to one side, clear of the frame. Reassembly requires a similar technique with the pushrods recessed as far as possible into the cylinder head. The longer pushrods are the inlets and are fitted inboard. As the head is slid into position between the cylinder block and frame rails tho pushrods are dropped through tho pushrod tunnels and located on the cam followers. The head is then lowered into position and if necessary the rocker ball ends csn be engaged with the tops of the pushrods. July 1970 Norton Villiers Canada Limited