1986 Corvette: Service Bulletin: Spark Plug Service on Engines with Aluminum Heads
Subject: Spark Plug Service on Engines with Aluminum Heads
Model and Year: 1986 Corvette 5.7 L PFI L98 (VIN Code 8) Engine
Source: Chevrolet Dealer Sevice Bulletin
Bulletin Number: 86-82, Section 6A
Date: May, 1986
TO: ALL CHEVROLET DEALERS
Removing spark plugs from 5.7L PFI engines with aluminum heads for inspection, servicing or replacement is a relatively simple task, but it does require care and attention.
NOTICE: To remove spark plugs from engiens with aluminum heads, allow the engine to cool. the heat of the engine, in combination with a spark plug that has run for many hours, may cause the spark plug to seize.
Whenever spark plugs are to be reused, the crushable design gasket, P/N 5612328, must be replaced eatch time the spark plug is removed. The correct spark plug installation torque is 18-22 ft. lbs. (25-30 NM).
NOTICE: Over tightening of a spark plug can cause stretching of the spark plug shell and could allow blow by to pass through the gasket seal between the shell and insulator. Over tightening also results in extremely difficult removal.
Use applicable labor time and labor operation numbers for this operation.
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