1976 Corvette: Service Bulletin: Heater Hose Clamp Interference with A/C Evaporator Inlet Pipe

Subject: Heater Hose Clamp Interference with A/C Evaporator Inlet Pipe
Model and Year: 1976 Corvette with A/C
Source: Chevrolet Dealer Service Technical Bulletin
Bulletin Number: 76-T-43, Section Ia
Date: Nov. 1976


On some 1976 Corvettes, the heater hose clamp screw may rub against the evaporator inlet refrigeration pipe.  This condition could cause a hole being worn through the evaporator pipe resulting in a loss of freon.  For 1977 production models, this condition has been corrected by lengthening the heater hose.

1976 Corvettes, when serviced, should be checked for this condition.  If interference is evident, the following changes should be made:

  1. Loosen hose clamp and rotate to provide maximum clearance to the evaporator pipe.
  2. Insert a section of slit rubber hose over the evaporator inlet pipe in the area of the hose clamp. (See Figure 1)
  3. In the event the clamp screw has worn through and a loss of freon has taken place, it will be necessary to replace the evaporator core.

Recommended time for correction .3 hours.

Chevrolet Motor Division
General Motors Corporation

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.

© Copyright General Motors Corporation. All Rights Reserved

Article ID: 720
Created: August 2, 2014
Last Updated: August 2, 2014

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