1964 Corvette: Service Bulletin: Neutral Safety Switch Malfunction
Subject: Neutral Safety Switch Malfunction
Model and Year: 1964 Corvettes with Powerglide Transmissions
Source: Chevrolet Technical Service Bulletin
Bulletin No: DR #658
Date: March 10, 1964
TO: ALL CHEVROLET DEALERS
Interference between the neutral safety switch and the underbody may exist on some early production Corvette Models with Powerglide transmissions.
This could result in the engine being started while the transmission selector is in a drive position. In addition, the added load imposed on the shift linkage by the misalignment causes a reduction or loss of detent feel when the transmission is shifted manually. The transmission might then be accidentally operated between ranges and internal damage could result.
Correction of switch malfunction may be made by shimming the switch assembly downward as shown in the attached sketch. Note that operating clearance must exist between the switch body and the switch actuating rod after the shimming operation is completed.
Corrective measures have been taken at the plant effective with serial number S103661.