Triumph MAYFLOWER 1951, Instruction Book

Page: 48 / 86

47
RUNNING ADJUSTMENTS- Engine
Carburettor
The correct sizes of choke and jets are fitted to the carburettor and it is inadvisable
to alter them as they are the result of exhaustive bench and road tests.
Slow running adjustments are provided and these are the only points that may
require attention after the engine has become run-in. Two adjusting screws are
shown in Fig. 30, one for limiting the closing of the throttle and thus the idling
speed. The other screw regulates the strength of the idling mixture. There is also a
screw which sets the full open position. Don't interfere with this. With the latest
starting jet settings no air jets are fitted into the "start box."
CHOKE AND JET SIZES
SLOW RUNNING ADJUSTMENT. We recommend that the carburettor be adjusted to
run at a fairly fast idling speed, because an engine which is regulated to a minimum
speed when hot, is apt to stall when cold.
Commence with the regulator screw screwed out 1½ complete turns and the throttle
screw set to the lowest possible idle, and under these circumstances the engine
should have a tendency to " hunt." Now screw in the regulator screw until the
engine runs evenly. This may cause the engine speed to increase, in which case the
throttle screw should again be rotated until the engine idles slowly.