View Single Post
Old 04-30-2007, 06:01 PM   #451
Charlie-III
NASIOC Supporter
 
Member#: 30669
Join Date: Dec 2002
Chapter/Region: Tri-State
Location: USA, North NJ, 07456
Vehicle:
1998 Legacy 2.5GT
Silver Sleeper BK, 5MT

Default

Quote:
Originally Posted by hiremichaelreid View Post
Well now that I've read the entire thread and some associated links it's clear that this threads main thrust is the head gasket problems on 2.5 L EJ25 engines, regardless of vehicle.

My take is that a bad head gasket design is the source of the problems. It appears this affects model year 1996 (or 95?) to 1998 or 1999 phase 1 DOHC engines the worst (with internal leaks). Appears to be a little better (external leaks) with 1999 or 2000 to 2002 phase 2 SOHC engines.
Actually, what is not really stated here is a block change over the years as well. The phase-2's and up had support ribs from the external walls of the block to the top of the cylinders. The phase-1's didn't. This allowed the cylinders to wiggle around which "wore a hole" into the HG.
Using later model HG's helped this, but did not totally fix it.

I finally fixed it by using a rebuilt STi 2.5L SB and my original DOHC heads.
* Registered users of the site do not see these ads.
Charlie-III is offline   Reply With Quote