Rochester 2Gv Carburetor; Idle Speed And Mixture Adjustment; Disassembly Of Bowl Cover - Pontiac Grand Prix Service Manual

ENGINE FUEL 6B-13
Fig. 68-26 Choke Coil Rod Adiustment
3. Bottom of rod end which slides into hole in choke
lever should lay freely in notch on the choke lever.
4. Bend choke coil rod at point shown to adjust.
5. Connect coil rod to choke lever and install retaining
clip.
ROCHESTER 2GV CARBURETOR
V-8 ENGINE
CARBURETOR ENGINE AND
MODEL TRANSMISSION
NUMBER USAGE
7029060..
.........................
.400
Auto. Trans.
7029062..
.........................
.350 Auto. Trans.
7028066..
.......................
.400 Manual Trans.
702807 1..
.......................
.350 Manual Trans.
ADJUSTMENTS ON CAR
AU Rochester 2GV adjustments can be performed on
the car. With the exception of idle speed and mixture
adjustment all adjustments are included in the OVER-
HAUL AND ADJUSTMENTS procedure. Following
are idle speed and mixture adjustments.
IDLE SPEED AND MIXTURE ADJUSTMENT
With engine at operating temperature adjust idle
speed following the procedure at the end of Section
6D.
Whenever the idle screw is turned to adjust idle, the
throttle should be opened slightly, then closed to seat
throttle lever extension on the screw.
The idle mixture should be adjusted to give best lean
idle at specified idle speed. Missing is a sign of too
lean an idle mixture while rolling or loping indicates
too rich a mixture. Turning idle mixture screw in, leans
out mixture; foru turns out from lightly seated
position may be used as a premilinary setting fo
mixture screws: mixture to be leaned out from this
setting to achieve best lean idle.
PERIODIC SERVICE
There are no periodic services required on the
Rochester 2GV carburetor; however, choke linkage,
choke valve and levers and pump linkage should be
kept free of dirt and gum so that they will operate
freely. DO NOT OIL CHOKE VALVE SHAFT OR
ANY PART OF THE LINKAGE.
OVERHAUL AND ADJUSTMENT
Flooding, stumble on acceleration and other perform-
ance complaints are, in many instances, caused by
presence of dirt, water 8r other foreign matter in
carburetor. To aid in diagnosing the cause of com-
plaint, the carburetor should be carefully removed
from engine without draining fuel from bowl. The
contents of fuel bowl may then be examined for
contamination as carburetor is disassembled.
The following is a step-by-step sequence by which the
Rochester 2GV carburetor may be completely disas-
sembled and reassembled. Adjustments may be made
and various parts of the carburetor may be serviced
without completely disassembling the entire unit.
DISASSEMBLY OF BOWL COVER
1. Remove fuel inlet filter retainer nut and gasket (Fig.
6B-27) and remove filter.
2. Disconnect pump link (Fig. 6B-28) from pump lever
by removing spring clip. Remove lower end of pump
rod from throttle lever by removing clip.
3. Detach choke coil rod (Fig. 6B-27) from choke shaft
lever after removing retaining clip.
4. Remove retaining screw at end of choke shaft and
remove choke trip lever and fast idle link and lever
(Fig. 6B-28). Lever can be removed from link by
turning until slot in lever will pass over tang on link.
The link and fast idle lever are retained by a Truarc
washer. Disassembly of these pieces will destroy
Truarc washer.