Ford Manual
What is the Valve Arrangement?
Answer No. 21
One intake and one exhaust valve are located in each cylinder. The former admits the fresh gas drawn
from the carburetor through the inlet pipe---the latter permits the exploded gas to be driven out through
the exhaust pipe. The valves are alternately opened and closed (see Cut No. 2) by the cams on the cam
shaft striking against push rods which in turn lift the valves from their seats.
What about Valve timing?
Answer No. 22
In timing the engine the points of opening and closing of the valves are, of course, what should be
considered. As the valves are properly timed at the factory when the engine is built the necessity for
retiming would occur only when such parts as the cam shaft, time gears or valves were removed in
overhauling the engine.
The time gears must mesh so that the tooth marked "Ford" on the small time gear will come between the
two teeth on the large gear at the point marked zero (0). The time gears now being properly set, the
exhaust valve on No. 1 cylinder is open and the intake valve closed, the other valves being in the
position indicated in Cut No. 2. The opening and closing of the valves being as follows: The exhaust
valve opens when the piston reaches 5/16" of bottom center, the distance from the top of the piston head
to the top of cylinder casting measuring 3-3/8". The exhaust valve will close on top center, the piston
being 5/16" above the cylinder casting. The intake valve opens 1/16" after top center, and closes 9/16"
after bottom center, the distance from the top of the piston to the top of the cylinder casting measuring 3-
1/8".
What about the care of the Valves?
Answer No. 23
