THE ECONOMY LEVER CONTROL.

The economy lever (see Fig. 2, page 3) performs four functions -

So long as the engine is cold, the economy lever should remain in the rich mixture position (see Fig. 2b) In this position the water valve is nearly closed, which helps the engine to warm up more quickly. There is a winter and a summer connection between the economy lever and the water valve, and the former should he used so long as the water keeps cool enough when hill climbing.

When the engine is warm. as indicated by the thermometer on the radiator cap, the economy lever should be moved as far toward the weak mixture end of its quadrant as is consistent with the power (see Fig. 2c). In. this position, the economy lever partially closes the petrol regulator, and the quickest method of finding the best adjustment is to move the lever right back and then to advance it slightly if there is any "popping" or "dryness" such a sometimes gives the, impression that the brakes have been momentarily applied.

After hill climbing, additional oil can he supplied to the cylinder head, by temporarily moving the economy lever a notch or two along the primer portion of the quadrant.

THE PRIMER AND PILOT JET

The Daimler primer serves two distinct purposes.

1. As a primer it draws liquid petrol through a fine tube straight from. the float chamber into the, induction pipe on the engine side of the throttle, and the engine then depends for its air supply on the throttle itself being slightly open.
2. When out of action as a primer, it is in action as a pilot carburettor. It is then complete with its own air supply and is large enough to enable the engine to run idle with the throttle shut.

When the engine is cold, it may be necessary slightly to open the primer in order to enrich the pilot mixture, but if this is also necessary when the engine is warm, a permanent re-adjustment of the pilot jet should be made by turning clockwise the milled nut on the top of the primer.

When the engine is cold the temporary use of the primer will much improve the pick-up under load, but it must be remembered that the primer is most effective when the throttle is nearly closed and the primer is full open. Care must be taken not to leave the primer permanently in action.