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Old 02-07-2013, 01:27 AM   #26
jamal
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Quote:
Originally Posted by Bluefoton View Post
it'd be nice to clear that up once and for all. So 642s for EJ251 and 770 for EJ253? Is there any difference in between coolant passages on the head in these two N/A engines?
Phase 1 dohc is -610, which is a thicker MLS gasket
Phase 2 sohc to somewhere around 08-09 should use -642, which is the 04-06 turbo gasket. So that includes the 251 and 253 I think.
09 ish and up already have the -770 MLS gasket in them, which is the same thickness as 642 but has different cooling passages.

I think the change was whenever they started putting avcs or avls or whatever it is on the n/a 2.5s.
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Old 02-07-2013, 11:50 AM   #27
Sir-Knight
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I believe that year would've been 05 in USDM, if not 06 for sure.
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Old 02-09-2013, 01:02 PM   #28
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Aren't coolant passages supposed to match the holes in the head/block? If the head design didn't change in between 07-08-09, why would the HG differ?
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Old 02-09-2013, 02:16 PM   #29
jamal
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Yeah, the head design did change. If avcs was added in 05-06 I guess that's not when it was, but I remember seeing an 09 or '10 outback with the new -770 gaskets.

There's a picture of it here:

http://forums.nasioc.com/forums/show....php?t=2155089
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Old 02-12-2013, 10:30 PM   #30
cdwahl
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Quote:
Originally Posted by jamal View Post
Phase 1 dohc is -610, which is a thicker MLS gasket
Phase 2 sohc to somewhere around 08-09 should use -642, which is the 04-06 turbo gasket. So that includes the 251 and 253 I think.
09 ish and up already have the -770 MLS gasket in them, which is the same thickness as 642 but has different cooling passages.

I think the change was whenever they started putting avcs or avls or whatever it is on the n/a 2.5s.
What about for valve cover gaskets, will the dealer have MLS?

I need to replace my valve cover gaskets and I am not excited to install the same ones that failed after 60-90k...

Last edited by cdwahl; 02-12-2013 at 10:31 PM. Reason: typos...
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Old 02-13-2013, 12:36 AM   #31
rhino6303
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Quote:
Originally Posted by cdwahl View Post

What about for valve cover gaskets, will the dealer have MLS?

I need to replace my valve cover gaskets and I am not excited to install the same ones that failed after 60-90k...
The valve cover gaskets are not steel. So you can't get any mls valve cover gaskets. The oem ones work fine as long as you follow the fsm and also make sure all surfaces are clean when installing.
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Old 02-13-2013, 10:35 PM   #32
cdwahl
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So you think that they failed because they weren't installed properly at the factory?
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Old 02-14-2013, 12:26 AM   #33
rhino6303
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They are a wear item. Getting 90k out of the valve cover gaskets is great.
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Old 02-17-2013, 10:36 AM   #34
MikeC5
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So has anyone used the 11044AA642 (MLS) gaskets on an 2.5 NA? Specifically, for a 2002 engine.
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Old 02-17-2013, 11:32 AM   #35
rhino6303
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Yes. It has been done a lot on 2.5 n/a motors all the way up until they changed the coolant chamber designs.
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Old 02-17-2013, 12:11 PM   #36
walhalla
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how much is compression is effected
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Old 02-17-2013, 12:43 PM   #37
Bluefoton
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0.1 increase in CR
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