EXPERTEC TSB (431214)

Publication date: 1994-04-19
Reference number: 431214

EXPERTEC TSB

TECHNICAL SERVICE BULLETIN

Reference Number(s): 431214, Date of Issue: 04/19/94

HEATER WARMS UP SLOWLY (INST. - PLUG IN RADIATOR VENT HOSE)

Model(s): 1994 Buick Roadmaster, 1994 Chevrolet Caprice, 1994 Cadillac Fleetwood

Bulletin No.: Buick 431214, Chevrolet 431214, Cadillac 431214

Date: 04/19/1994

SUBJECT

HEATER WARMS UP SLOWLY (INSTALL PLUG IN RADIATOR VENT HOSE)

MODELS

1994 BUICK ROADMASTER 1994 CADILLAC FLEETWOOD 1994 CHEVROLET CAPRICE

CONDITION

SOME OWNERS MAY COMMENT THAT THEIR VEHICLE WARMS UP SLOWLY.

CAUSE

COLD COOLANT IS ENTERING THE HEATING CIRCUIT AT THE RECOVERY BOTTLE THROUGH THE COOLANT RECOVERY RADIATOR (RESERVOIR TO RADIATOR) HOSE (ALSO REFERRED TO AS THE RADIATOR VENT HOSE).

CORRECTION

PERFORM THE FOLLOWING MODIFICATION TO RESTRICT FLOW TO THE COOLANT RECOVERY BOTTLE FROM THE RADIATOR.

CAUTION: THE FOLLOWING PROCEDURE INVOLVES MODIFICATION OF A COOLANT HOSE. ANY COMPONENT OF THE COOLANT SYSTEM ON THESE VEHICLES MAY CONTAIN HOT COOLANT UNDER PRESSURE. ALLOW THE VEHICLE TO COOL THOROUGHLY BEFORE PERFORMING THIS MODIFICATION.

AFTER ALLOWING VEHICLE TO COOL THOROUGHLY, SLOWLY REMOVE CAP FROM PRESSURIZED COOLANT BOTTLE.
LOCATE THE COOLANT RECOVERY RADIATOR (RESERVOIR TO RADIATOR) HOSE (SEE ILLUSTRATION). OUTSIDE DIAMETER OF HOSE IS APPROXIMATELY 5/8" (16 MM).
REMOVE HOSE FROM THE PRESSURIZED BOTTLE ONLY.
INSERT A 3/8" (9.5 MM) DIAMETER X 1" (25.4 MM) LONG PLUG INTO THE VENT HOSE (A STUD WORKS WELL IN THIS APPLICATION). USING THE APPROPRIATE TOOL, PUSH THE PLUG AT LEAST 1-1/4" (31.8 MM) INTO THE HOSE.
INSTALL AN APPROPRIATE SIZE HOSE CLAMP ON THE HOSE CENTERED ON THE PLUG. THIS CLAMP WILL PREVENT THE PLUG FROM MOVING AS WELL AS SEAL THE HOSE TO THE PLUG IN ORDER TO PREVENT COOLANT FLOW THROUGH THE HOSE.
INSTALL THE COOLANT RECOVERY RADIATOR HOSE BACK ON THE PRESSURIZED COOLANT BOTTLE.
CHECK COOLANT LEVEL AND ADD AS NECESSARY.
INSTALL CAP ON PRESSURIZED COOLANT BOTTLE.

BULLETIN ILLUSTRATION LIST

Fig 1: Graphic

WARRANTY INFORMATION

FOR VEHICLES REPAIRED UNDER WARRANTY, USE

LABOR OPERATION: J3252

LABOR TIME: 0.2 HR.