Carburetor Float - External Level Checking Tool
Bulletin 84-6C-15Date Aug.'84
Ref.No. 84-225-6C
SUBJECT: NEW REVISED TOOL FOR EXTERNALLY CHECKING CARBURETOR FLOAT LEVEL
MODELS AFFECTED: ALL MODELS EQUIPPED WITH DUELJET AND QUADRAJET CARBURETORS
QUADRAJET/DUALJET FLOAT LEVEL GAUGESNew Float Level Gauge:
Enclosed are three (3) new External Float Level Gauges, as shown in figure 1, for checking the Float level on all Quadrajet and Dualjet carburetors. the new gauge, tool number J-34935-1 or BT-8420A, corrects for the design variables of the past several years that may have led to occasional inconsistent Float level readings when the original gauge was used.
To correct for this, a new series float level gauge has been released which replaces the current J-9789-130 or BT-7720 gauges, (Figure 1).
The new gauge special tool numbers, which are also used to check mixture control (M/C) solenoid plunger (paddle) travel, are J-34935-1 and BT-8220A, (figure 1).
Figure 2 - External Checking of Float Level:
Figure 3 - Checking Mixture Control solenoid Plunger Travel:
The procedure for external checking of the float level and (M/C) solenoid plunger (paddle) travel has not changed, and are illustrated in (figures 2 and 3).
IMPORTANT: All previously provided float level gauges J-9789-150 and BT-7720 white in color should be disposed of upon receipt of the (3) new gauges supplied with this bulletin. Use only the new (black) gauge for all future external carburetor measurements.
Figure 2 - External Checking of Float Level:
1. WITH ENGINE IDLING AND CHOKE WIDE OPEN, INSERT GAGE IN VENT SLOT OR VENT HOLE. ALLOW GAGE TO FLOAT FREELY.
NOTICE: DO NOT PRESS DOWN ON GAGE. FLOODING OR FLOAT DAMAGE COULD RESULT.
2. OBSERVE THE MARK ON GAGE THAT LINES UP WITH TOP OF CASTING. SETTING SHOULD BE WITHIN +/- 2/32" (1.588 mm) OF SPECIFIED FLOAT LEVEL SETTING.
INCORRECT FUEL PRESSURE WILL ADVERSELY AFFECT FUEL LEVEL.
3. IF NOT WITHIN SPECIFICATION, REMOVE AIR HORN AND ADJUST FLOAT.
Figure 3 - Checking Mixture Control solenoid Plunger Travel:
1. PLACE J-34935-1 OR BT-8420A IN "D" SHAPED VENT HOLE. ALLOW GAGE TO TOUCH SOLENOID PLUNGER.
2. OBSERVE MARK ON GAGE THAT LINES UP WITH CASTING.
3. PUSH GAGE DOWN UNTIL PLUNGER IS IN "DOWN" POSITION, AND OBSERVE DIFFERENCE IN GAGE READINGS. THE SOLENOID PLUNGER TRAVEL SHOULD BE BETWEEN 2/32" AND 6/32".