Should the rockers and valve springs, etc., not have been removed, proceed to refit the valves as described later, but if the rockers and springs have been taken out the oil seal washers from the tops of the Inlet and Exhaust guides should be inspected. If the exhaust has been excessively smoky, or if the oil seal washers are worn or hard they should be replaced with new ones (Catalogue Nos. K252 and K253).

To refit first put in the valve spring bottom washer, the oil retaining washer and cap, the springs and the top washer, and compress the springs using the small washer SL6/35 as previously described. Put back the rocker, making sure that the rocker bush is quite clean. Clean the rocker spindle, oil the bearing surface, and screw it back into place, not forgetting the rocker thrust washer which is fitted between the left-hand side of the rocker and the threaded end of pin. Screw in the rocker spindle as far as it will go, but do not use force. Now unscrew the spindle until the "V" or arrow marked on the end of the spindle inside the hollow end of the hexagon is, in the case of the exhaust valve (the front one), facing the rear, or in the case of the inlet valve, facing the front. An illustration appears on another page showing the exact location of the pins. Having refitted the rocker, release the valve springs again, see that the valve guide is clean, wipe the valve stem with clean oil or grease and put the valve into position. It may be necessary to manoeuvre the valve spring about a little to let the valve stem pass through the oil seal and its cap. Having made sure that the valve is on the seating, refit the valve spring remover and compress the springs until it is possible to get the cotter into place. See that the cotter is properly engaged with the groove on the stem, and when this has been done release the screw so that springs will return to their correct position. Having refitted both valves and rockers, the valve clearances can be reset before the head is put back on to the engine, but it is desirable before setting the clearances to make sure that the camshaft has not been moved and that the marks on the bevels are in register. Here again reference to the illustration should make matters quite clear. The clearances are set by turning the rocker spindles to move the "V" marks or arrows downwards to decrease the clearance or upwards to increase them. Set the inlet clearance to .006-in. and the exhaust to .010-in. for running. These clearances are correct for a cold engine.