NEW FLOAT LEVEL GAGE CARBURETOR INFORMATION

Subject: NEW FLOAT LEVEL GAGE FOR DUALJET AND QUAD- RAJET CARBURETORS

Model and Year: ALL WITH DUALJET AND QUADRAJET CARBURETORS

Enclosed are three (3) new external float level gages, as shown in Figure 1, for checking the float level in all current Quadrajet and Dualjet carburetors.

The new gage, P/N J-34935-1 or BT-8420A, reflects the design variables of the past several years that may have led to occasional inconsistent readings when the older gage was used. The new gage is also suitable for checking the float level of all past model quadrajet and dualjet models, and in checking mixture control solenoid plunger travel.

The procedure for external checking of Float Level has not changed (see Figure 2).

The procedure for checking Mixture Control Solenoid Plunger Travel on E4MC, E4ME, E2MC, and E2ME models has not changed, and is outlined in Figure 3.

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" (1.588mm) of specified float level setting.

INCORRECT FUEL PRESSURE WILL ADVERSELY AFFECT FUEL LEVEL.

3. If not within specification, remove air horn and adjust float.

The new gage replaces J-9789-130 or BT-7720, which should be discarded and should no longer be used.

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".

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.