Difference between a 'phase 1' vs 'phase 2' EJ25 engine
I'm currently rebuilding a 1998 Subaru legacy outback DOHC 2.5 liter engine due to a
failed head gasket. During my time in both repairing the engine and divulging into the
world of the EJ25 engine, I've found myself stumped by the phase 1 and phase 2 term
associated with this engine model. I know that my 1998 engine is a phase 1, but from
what I've been reading the phase 2 appeared during the 1999 model. Possibly when
they updated the outback body design to a more curvier appeal as seen from the 2000
My questions are:
What is the difference between phase 1 and phase 2? I know the 1998 outback can
only run phase 1 with the stock wiring harness
Does this phase term refer to the heads? DOHC and SOHC
Are all 1999 subaru model phase 1? or a mix of both.
And will a 1999 phase 1 engine be compatible with my 1998 phase 1 wiring harness?
Thanks for all of your time!! It is truly appreciated
Hi, I have a 2010 Subaru Outback 2.5 Limited that has the phase 2, EJ25 series engine. I can't answer about the wiring harness, but, you should know that the phase 2 engines starting in 2010 had the multi layered head gaskets. This is significant enhancement over the previous years resulting in a much better system to seal up the dual heads. As you know, having two heads is a blessing and curse. As far as I know, all of these phase 2 engines had the SOHC . It wasn't until they introduced the new FB series engine and the different valve placement. Unfortunately, a lot of these newer engines burn oil. Good luck.
I never knew really, so I Googled>> subaru forester phase 1 2 gasket << and found these two sites: http://users.sisna.com/ignatius/subaru/headgasket.html AND http://www.smart-service.com/store- head-gaskets.html Which seems to be phase 1 DOHC and phase 2 SOHC. I don't know what all they offer anymore, I truly only follow early foresters up to about 04/05.
Found this for you online "The phase 1 is a DOHC engine, the phase 2 is a SOHC. It's hard to describe on a computer without showing you a pic, but probably the easiest way to spot the difference is to look at the black cam/belt covers at the front of the engine (directly in front of the radiator). The DOHC engine will have two "humps" for the camshafts, the SOHC only one."
Thank you both very much for your help and time! It is truly appreciated and you have helped me immensely with my project!
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