Ford 231 Operator's Manual page 59

ENGINE SPEED ADJUSTMENT
DIESEL
The maximum no-load and idle speeds of the engine
are set by adjustments on the pump at the factory.
It should be adjusted only by a qualified diesel mechanic
at your Ford Tractor-Equipment Dealer.
Maximum Low
No-Load RPM Idle RPM
Ford 335, 231 2225-2275 600-700
Ford 420, 515,
532, 535, 531 2425-2475 600-700
GASOLINE
Constant engine speed for any throttle setting is provided
by a centrifugal governor. The governor is driven by the
engine timing gears and connected by linkage to the
throttle plate on the carburetor. See your Ford Tractor-
Equipment Dealer for adjustments.
Maximum Low
No-Load RPM
Idle RPM
Ford 335, 231, 420 2185-2285 600-700
Ford 515, 532, 535,
531 2395-2495 600-700
Figure 88
Gasoline Engine
1. Air Cleaner Restriction Gauge
3. Clean the element by tapping it against the palm
of your hand.
NOTE: Compressed air not to exceed 100 psi
(7,05 kg/cm2) may be used for cleaning. Blow
dust from the inside to the outside by inserting
the nozzle inside the element.
4. Clean the inside of the canister with a damp, lint-
free cloth.
AIR CLEANER
Checking the Air Cleaner Restriction Gauge: Check the
air cleaner restriction gauge (1), Figure 88, daily or
every 10 hours.
Check the gauge visually; if red can be seen through
the sight glass, clean the primary air cleaner element.
Then reset the gauge by depressing the button on top
of the gauge.
Cleaning the Primary Element and Inlet Cap: Clean the
air cleaner element and inlet cap whenever the air cleaner
restriction gauge shows red.
1. Remove the air cleaner retaining screw and cover
(1), Figure 89, and pull the element from its lo-
cation, Figure 90.
2. Check the rubber seal (3), Figure 90, on the ends
of the element for adhesion. If they are loose or
damaged, install a new element.
Figure 89
Servicing Air Cleaner
1. Retaining Screw and Cover
57