Modification of Timing Belt Tensioner Bracket on 2004-2005 Subaru Engines - Engine Builder Magazine

Modification of Timing Belt Tensioner Bracket on 2004-2005 Subaru Engines

Affected applications: 2004MY Forester; 2005MY Legacy and Impreza

On SOHC engines, the shape of the bracket and the size of the 2 (upper side) installation bolts were changed. On DOHC engines, the shape of the bracket was changed and ribs added to increase rigidity.

PRODUCTION LINE CHANGE

The new style tensioner brackets were used in production starting in February 2004.

*See Chart 1 for MY VINs and part number information.

REVISED TENSIONER

A revised timing belt tensioner has been incorporated in production since April, 2002. A new heat treatment procedure was used to improve the hardness of the surface at the plunger to prevent poor sealing.

Identification revised belt tensioner

The color of the paint dot on the pulley bolt was changed from "Blue" to "Green" (see Figure 1). Lot number of belt tensioner: 020402 and after.

REPAIR PROCEDURES/INFORMATION

Installers must identify if noise is coming from the timing belt tensioner or tensioner bracket when the engine is cold.

1) With the hood raised, listen carefully where the noise is coming from. If the noise can be heard from around the timing belt cover area, there is a possibility that the noise is coming from the timing belt tensioner.

2) Confirm if the noise is coming from the upper portion of the timing belt tensioner by using a stethoscope. If noise can be heard it’s either coming from the tensioner or bracket.

Inspect the belt tensioner: if the cylinder body of the timing belt tensioner has a notch from wear (see Figure 2) the tensioner will need to be replaced.

3) If the engine number is 572570 for SOHC or 572928 for DOHC and after, replace the timing belt tensioner bracket.

(4) If the engine number is 572570 for SOHC or 572928 for DOHC and before, check to see if the cylinder body of the timing belt tensioner has a wear notch. If so, replace the timing belt tensioner. Ifthe cylinder body of the timing belt tensioner does not have a wear notch, replace the timing belt tensioner bracket.

Some or all of this information was provided by the Automotive
Parts Remanufacturers Association (APRA). For more information on
technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.
chart 1figure 1Figure 2

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