Subject: Crankshaft to Water Pump Drive Belt Failure
Model and Year: 1966 - 1967 Corvettes with 427 CU. IN. Engine and Air Conditioning
Source: Chevrolet Service Technical Bulletin
Bulletin No: 67-T-26
Section: VI
Date: Sept. 26, 1967
TO: ALL CHEVROLET DEALERS
Reports have been received of crankshaft to water pump drive belt failures on 1966 and 1967 Corvettes equipped with 427 cubic inch engine and air conditioning. The belt failure occurs when the air conditioning compressor stalls under high head pressure after extreme hot soak conditions. With the compressor stalled, the water pump and the drive belt between the crankshaft and water pump also stall. As the crankshaft pulley continues to rotate, the crankshaft to water pump drive belt fails due to overheating and wear.
To permit belt tension adjustment between the crankshaft and water pump, 1968 Corvettes equipped with 427 cubic inch engine and air conditioning will incorporate an idler pulley shown in Figure 1.
In service, a similar idler pulley and longer drive belt can be installed to permit belt tension adjustment and correct the condition of belt slippage and wear. Parts information and installation instructions are illustrated in Figure 1 on the reverse side.
Chevrolet Motor Division
General Motors Corporation
Article ID: 950
Created: October 8, 2014
Last Updated: October 8, 2014
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1966-1967-corvette-service-bulletin-crankshaft-to-water-pump-drive-belt-failure-950.html