Bulletin
9D-6
August, 1951
Model "B"
Page 9
ROCHESTER PRODUCTS DIVISION, GENERAL MOTORS CORP., ROCHESTER,
NEW YORK
THROTTLE BODY DISASSEMBLY
1. Remove Idle Adjusting Needle
and Spring.
Due to the close tolerance of the
Throttle Valve fit that is required, and the fact that the Idle Discharge
holes are drilled in relation to a proper fitting valve, Throttle Valve
and Shaft should not be removed. Standard carburetor cleaning solvent and
compressed air will serve to clean all passages.
INSPECTION OF PARTS
1. Check Floats for dents or wear at hinge pin
holes, replace if necessary.
2. Examine float needle and seat, if grooved
replace with a factory tested and matched float needle seat and gasket
assembly.
3. Check choke shaft for wear in the bores. If
worn excessively replace part.
4. If throttle shaft or valve appears loose due
to wear, replace throttle body assembly.
5. Inspect Pump Link and holes in pump and
throttle levers, if worn out of round, they should be replaced.
6. If gaskets appear hard and brittle, always
replace with a new one to insure proper seal.
ASSEMBLY OF MODEL "B" CARBURETOR
1. Install Idle Needle and Spring finger
tight. As a temporary idle adjustment back out 1-1/2
turns.
2. Using a new Throttle Body Gasket attach
Bowl to Throttle Body. Tighten screws evenly and securely.
3. Place clean Pump Screen in bottom of bowl
and lock retainer into position.
4. Drop small aluminum ball in pump
well.
5. Place pump return spring into well and
center it by depressing it with finger.
6. Install pump plunger and connect pump link
to throttle lever and pump rod. Attach Pin
Springs.
7. Drop large steel ball into pump discharge
cavity of bowl. Place bronze spring atop ball. Pump Guide will now fit within opening,
press down until Guide is flush with Bowl surface and spread slot with screw
driver.
8. Place throttle kick lever spring on bowl
boss, with smaller hooked end against bowl. Rotate clockwise until small end engages lower
boss.
9. Attach throttle kick lever with screw and
washer. Flat portion of lever must be against Idle Screw.
