Spark Plug - Service on Engines With Aluminum Heads
Number: 86-82Section: 6A
Date: MAY, 1986
Subject: SPARK PLUG SERVICE ON ENGINES WITH ALUMINUM HEADS
Model and Year: 1986 CORVETTE 5.7L PFI L98 (VIN CODE 8) ENGINE
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 engines 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 each time the spark plug is removed. The correct spark plug installation torque is 18-22 ft.lbs. (25-30 N-M).
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.