Ford COUGAR 1968 Shop Manual page 469

PART 10-1
-
G e n e r a l Fuel System Service
10-9
been firmly established that the rough
idle is caused by a lean condition as
indicated on an exhaust gas analyzer.
I. Remove the carburetor.
2. Enlarge the secondary idle dis-
charge ports with a No. 70 (0.028-
inch diameter) drill'in a pin vise (Fig.
21). Coat the drill bit with grease and
''
slowly rotate the drill through the
port. Do not enlarge the ports be-
yond the specified drill size. After re-
moving the drill, make sure all of the
metal chips are removed.
LDJUSTING SCREW- 8 3 1 1 5 - A
3. Install the carburetor and ad-
just the speed and mixture to the spe-
FIG. 25-Fast
( c o l d Engine) Idle
cified rpm and air-fuel ratio, using a
ADJUSTMENT SCREW 8 2 4 1 6 . ~
S p e e d Adjustment-Holley Model
tachomkter and exhaust gas analyzer.
After the secondary idle discharge
ports have been enlarged and the air-
fuel ratio and idle condition are satis-
factory, stamp or scribe the letter R
on the carburetor identification tag
just above the name Autolite to indi-
cate that the carburetor has been re-
worked.
FIG. 22-Idle
S p e e d Adjustments
Autolite Model 1'1 00 1 - V
FAST IDLE ADJUSTING SCREW
I
0.028.1NCH DRILL
FAST IDLE CAM
82595-A
FIG. 23-Fast
(Cold Engine) ldle
S p e e d Adjustment-Autolite Model
2 100 2-v
FIG. 2 7 -Secondary
ldle Discharge
Ports Enlargement-Holley Model
41
50-C
4-V C a r b u r e t o r
FAST (COLD E N G I N E ) IDLE
SPEED ADJUSTMENT
All Autolite a n d 4-V Holley
Carburetors
The fast idle adjusting screw (Figs.
22 thru 25) contacts one edge of the
fast idle cam. The cam permits a fas-
ter engine idle speed for smoother
running when the engine is cold during
choke operation. As the choke plate
is moved through its range of travel
from the closed to the open position,
the fast idle cam pick-up lever rotates
the fast idle cam. Each position of the
FIG. 24-Fast
(Cold Engine) ldle
S p e e d Adiustment-Autolite Model
4300 4-v
fast idle cam permits a slower idle
rpm as engine temperature rises and
choking is reduced.
Make certain the idle (hot engine)
speed and mixture is adjusted to spe-
cification before attempting to set the
fast idle speed.
I. With the engine operating tem-
perature normalized (hot), air cleaner
removed and the tachometer attached,
manually rotate the fast idle cam un-
til the fast idle adjusting screw rests
on the center step on the cam.
2.
Start the engine. and turn the
fast idle adjusting screw inward or
outward as required to obtain the
specified idle rpm (Part 8-5).
Carter Model YF 1 - V
The carburetor must be removed
from the engine to check or correct
the fast idle speed adjustment.
I. Open the throttle plate and
hold the choke plate fully closed to
allow the fast idle cam (Fig. 26) to
revolve to the fast idle position.
2. Close the throttle and use a
drill with a diameter equal to the
specified clearance to check the clear-
ance between the throttle plate and
throttle body bore (Fig. 26). T o adjust
the clearance, bend the choke connec-
tor rod in a direction to open or close
the throttle as required.
ANTI-STALL DASHPOT
ADJUSTMENT
The anti-stall dashpot adjustment
is made with the air cleaner removed
from the vehicle.
Autolite Model
1 100 1
-V
1. Adjust the throttle position to
the hot idle setting. Turn the dashpot
adjusting screw outward until it is clear
of the dashpot plunger assembly
(Fig. 27).
2. Turn the dashpot adjusting