Cadillac 1937 LaSalle VVI Information page 189

101
E N G I N E
A u t o m a t i c C h o k e A d j u s t m e n t
Except for a check of the m o v i n g parts to see
that they operate freely a n d an occasional clean-
ing of the hot air line, no adjustment of the
automatic choke control unit should be necessary.
If the initial and part throttle running mixture is
too lean or too rich, revolve the thermostat
housing as indicated on the housing face.
A c c e l e r a t i n g P u m p A d j u s t m e n t
Adjustments are provided for a short and a long
pump stroke: A short stroke to be used for hot
temperatures a n d a long stroke to be used for
extremely cold temperatures.
Note: Lubricate countershaft that operates
accelerating pump every 6,000 miles.
Shaft is lubricated under the grease cup
cover on the float bowl housing.
Increased resistance o n the foot throttle indi-
cates a clogged pump jet. P u m p jets and check
valves should be removed a n d cleaned. A l l jets
and valves must be seated gasoline-tight when
replacing. Poor acceleration m a y be due to a
loose plunger, a worn or damaged plunger leather,
or a partly plugged jet. If necessary, replace the
plunger spring and leather, m a k i n g sure that the
nut inside the plunger cup is screwed d o w n tight
to avoid air leaks. Use T o o l J-507 for replacing
plunger i n cylinder.
M e t e r i n g R o d A d j u s t m e n t
1. R e m o v e air horn a n d automatic choke
assembly by removing two air horn attaching
screws and one screw under choke valve o n inside,
and disconnect upper end of throttle connector
rod.
2. B a c k o u t throttle lever adjusting screw so
that throttle valves close tight.
3. R e m o v e p i n spring from metering rod pins
and slide the p i n out of the metering r o d arms,
taking care. that p i n spring and metering rod
springs are n o t damaged i n any way. L i f t o u t
metering rods a n d remove retainer plate b y
loosening small screw. R e m o v e the t w o small
discs beneath this plate.
4. Insert two metering rod gauges, T o o l J-510,
in place of the metering rods, seating tapered
end' i n metering rod- jets. P u t metering r o d
pins i n place. Check position of metering rod
pins which should now rest lightly on lower end
of notch i n gauge w i t h the throttle fully closed
and the upper end of the connector rod centered
in its hole i n the pump arm. B e n d throttle con-
nector rod to secure proper adjustment, i f above
conditions are n o t met.
5. ' R e m o v e gauge and replace metering rods
and discs, and connect metering rod spring. Place
small amount of graphite grease i n holes so that
the metering rod arm operates freely.
A n t i - P e r c o l a t o r A d j u s t m e n t
1. Set throttle valve to give .020 inch clearance-
between edge of throttle valve and throttle bore
on side opposite port, using T o o l J-512.
2. Adjust metering rod arms so 'that there is
.005 to .015 inch clearance between the lip and
the valve stem of each unit, taking care that
both valves are adjusted equally.
Note: D o not disturb setting of metering rods
during this adjustment.
3. Check adjustment after metering rods are
installed as a final check on the work.
S l o w a n d F a s t I d l e A d j u s t m e n t
1. M a k e sure that correct slow idle adjustment
(6 m . p. h.) has been made.
2. W i t h the fast idle screw resting against the
high lobe of the fast idle cam, check the clearance
between the throttle lever adjusting screw and
the carburetor casting stop, as shown in the
illustration. Plate 43, F i g . 60.
3. Adjust clearance to final setting of .030
inch for correct operation.
D e c h o k i n g A d j u s t m e n t
1. Check distance between upper edge of
choke valve and the wall of the carburetor air
horn when the dechoking device is open.
2. Measure opening which should be approxi-
mately inch and bend lip on fast idle connector
rod that contacts the choke trip lever, if it is
necessary to change position of valve.
37. I n s t a l l N e w R i v e t W h e n R e a s s e m b l i n g
V - 8 C a r b u r e t o r s
Whenever a Stromberg carburetor is dis-
assembled for cleaning or servicing and the split
rivet connecting the choke and the v a c u u m
cylinder linkage is removed, install a new split
rivet, P a r t N o . 1422729, when the carburetor is
reassembled.
T h e use of a new rivet is important because
otherwise, there is danger of the used rivet break-
ing off, going through the carburetor, and causing
considerable damage fco the engine.
38. C a r b u r e t o r A d j u s t m e n t
S e r i e s 37-85 a n d 90—The carburetors used o n
series 37-85 a n d 90 engines have only one adjust-
ment, the metering pin, which is raised or lowered
b y screwing i t into or out of the fuel orifice. See
Plate 44. T u r n i n g the p i n clockwise moves the
pin u p w a r d into the orifice and makes the mixture
leaner; turning i t counter-clockwise increases the
orifice opening a n d makes the mixture richer.
It is necessary, when adjusting these carbur-
etors, to make the semi-automatic choke thermo-
stats inoperative. S i m p l y warming u p the engine
is not enough because raising the hood cools the
thermostats enough to apply the choke slightly.
Whenever the carburetor is to be adjusted,
therefore, the connection to the automatic choke
should be blocked down so that the choke is i n
the fully "off" position.