Engine - Piston Ring Modification
NO.: TSB-93-11-005DATE: August, 1993
MODEL: Various (See Below)
SUBJECT:
DESIGN CHANGE TO # 1 PISTON RING
BACKGROUND INFORMATION
This bulletin describes a design change to the # 1 piston ring on 4G63 and 4G64 engines. Engines with these re-designed # 1 piston rings are used in several 1993 vehicles built from 05/01/92.
AFFECTED VEHICLES
1993 Galant, 2.0L, 4G63 Engine (SOHC, DOHC, and DOHC Turbo)
1993 Eclipse, 2.0L, 4G63 Engine (DOHC, and DOHC Turbo)
1993 Expo/Expo LRV, 2.4L, 4G64 Engine
1993 Truck, 2.4L, 4G64 Engine
DESCRIPTION
The shape of the # 1 piston ring used on 1993 vehicles with 4G63 and 4G64 engines has been changed. Previously, the cross-view of the # 1 ring was a flat rectangle. On vehicles built from 05/01/92, ALL 4G63 and 4G64 engines utilize a # 1 ring with a bevel on the interior (piston) side of the ring. This is the same design already used for the # 1 ring on DOHC turbo engines.The design change is not applicable to vehicles built before 05/01/92.
INSTALLATION NOTE
When installing the new # 1 piston ring, be sure the bevel is pointed UP, as shown in the illustration.
For complete piston ring installation instructions, refer to the 1 992-93 Engine Overhaul Manual, Group 11-F.
PARTS INFORMATION
The new # 1 piston rings are only available in complete engine ring sets. Order the piston ring sets from your facing PDC on a stock or daily order basis.
When ordering piston ring sets for vehicles described in this bulletin, refer to the current parts microfiche for part numbers.
NOTE:
Piston ring sets with the new # 1 ring ARE NOT useable on vehicles produced before 05/01/92.