At a glance it appeared my non-turbo SOHC 2.5 had been leaking antifreeze from the water pump. I installed a new pump but I still have the leak coming from somewhere above the pump. Could it possibly be the notorious external HG coolant leak that 04 Subaru 2.5L are known for?  What is the fastest way to pinpoint the origin of the leak without pulling the intake off? ughh.

Clean the engine, you can then use baby powder and see the coolant trail.  

04's do not leak coolant from the HG's. 

crossover?

 

you can get a rig to pressurize the system while you look for the leak

Edited October 25, 20187 yr by 1 Lucky Texan

9 hours ago, GeneralDisorder said:

04's do not leak coolant from the HG's. 

ah er o.k. Always thought all of them from 2000 up to about 2008 had that issue? I guess that's what I get for thinking? The last time I was thinking I put a heli coil in a tensioner bracket. quack.

Edited October 24, 20187 yr by darsdoug

13 hours ago, lmdew said:

Clean the engine, you can then use baby powder and see the coolant trail.  

I shall try that. Thanks Imdew.

99 to 02 leak coolant and oil, 03 to 10 leak only oil. Design change on the gasket. 

GD

GD, if you replace the HG with the new design on a 09-02, are they leak only oil after that?

 

 

1 hour ago, 3Pin said:

GD, if you replace the HG with the new design on a 09-02, are they leak only oil after that?

 

 

I suppose - but we use the 642 or 770 turbo 2.5 gasket that doesn't leak either. 

GD

10-4.  Thanks

GD do you still have good results surfacing the heads on a sheet of glass with Abrasive Cloth?

Yes that's how we do it. 1/2" glass and this is the cloth we use.

https://www.amazon.com/INDUSTRIES-4245-Emery-9-Inch-11-Inch/dp/B000BPNMZ4

We do a 2 step process - we rough both heads down with the new sheet, then we go back over both a second time with the "used" sheet. The grit of the cloth shears down and becomes finer leaving a smoother surface. I check the flatness with a granite surface plate, a machinists straight edge, and then the surface finish with an Ra meter. Ultimately my surface finish is comparable to what my cylinder head shop produces with their CBN flycutter. It's faster for us as there is no wait time for the machine shop and no drop-of/delivery. It's easier to just do it ourselves. 

GD

A good upper body work out for the day, with no gym fee.

It's especially fun when the shop gets up to about 100 degrees. 

so are you saying that I can use a 642 or 670 on a 99 outback with a 2.5L?

11044AA642 and 770 are the preferred MLS Turbo gasket for SOHC EJ25 engines

Edited October 31, 20187 yr by Mike104

22 minutes ago, whynot said:

so are you saying that I can use a 642 or 670 on a 99 outback with a 2.5L?

 

I did not say that. The 642 and 770 gaskets can be used on the SOHC EJ engines from 99 to 2012. 

They cannot be directly used on the 96 to 99 DOHC engines without changing the pistons. If you use 99 to 05 pistons you can then use the 642 or 770. Otherwise you absolutely cannot use them as the DOHC pistons will hit the chamber.

GD

great I was a little confused, so I asked. 

Thanks

 

It was just the thermostat seal leaking a little. A new one solved that mystery. quack quack quack.