Supporting Vendors / Dealers - Advertising - Shop

1968 Corvette: Service Bulletin: Whine Noise in Radio

Subject:   Whine Noise in Radio
Model and Year:   All 1968 Vehicles
Source:  Chevrolet Dealer Service Technical Bulletin
Bulletin No:   68-T-11
Section:   XII
Date:    January 2, 1968


On some 1968 vehicles, reports or noise, described as Delcotron whine emanating from the radio speaker, have been received.  This noise is most pronounced when the Delcotron charge rate is high and will vary in intensity when the volume control is adjusted.

An in-line filter designed to suppress Delcotron whine in radio speakers is now available through United Delco Distributors.

The filter should only be used after the following checks have been made to locate the source as being the Delcotron.

  1. Start and run the engine using all accessories (lights, heater, wipers, etc.) and listen for noise.  Operate volume control to determine if noise will vary.
  2. Disconnect the field connector (2 wire connector) from the back of Delcotron and again listen for the noise as in Step 1.

    1. If noise is not completely eliminated - Do Not add filter coil. Inspect radio per Bulletin TSB 66-7 "Radio Trouble Diagnosis", dated 7-28-66.
    2. If noise is completely eliminated - install filter coil per Step 3 below and re-evaluate as in Step 1.
  3. Install Filter Coil Assembly Part No. 1222834 in series with the three lead connector on the back of the radio. Tape the filter to the instrument panel wiring harness for support.

Note:  Filter Coil Assembly is available through Delco Distributors only.

Chevrolet Motor Disivion
General Motors Corporation

0 (0)
Article Rating (No Votes)
Rate this article
Attached Files
There are no attachments for this article.
There are no comments for this article. Be the first to post a comment.
Security Code Security Code
Related Articles RSS Feed
1965 - 1972 Corvette: Service News: Ignition Pulse Amplifier (SN-C-1)
Viewed 999 times since Thu, Oct 2, 2014
1973 Corvette: Electrical Schematic: Automatic Transmission Kickdown Switch
Viewed 919 times since Sun, Jul 13, 2014
1973 Corvette: Electrical Schematics
Viewed 705 times since Sun, Jul 13, 2014
1968 Corvette: Service News: 1968 Corvette 327 Cu. In. Engine Distributor Alignment
Viewed 2364 times since Sun, Jan 11, 2015
1968 Corvette: Engineering Service Letter: Engine Harness Replacement Corvette Transistor Ignition
Viewed 811 times since Mon, Sep 22, 2014
1979 Corvette: Service News: Corvette Auxiliary Cooling Fan Wiring Revision
Viewed 3609 times since Tue, Sep 16, 2014
1971 Corvette: Service Bulletin: Anti-Diesel Relay
Viewed 1067 times since Sun, Feb 8, 2015
1981 Corvette: ECM Codes
Viewed 1113 times since Fri, Aug 1, 2014
1982 Corvette: Service News: Fuel injection Diagnosis Chart
Viewed 1625 times since Sun, Oct 5, 2014
1969 Corvette: Service Bulletin: Choke Problems
Viewed 648 times since Sat, Oct 25, 2014