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More head gasket questions- 2.5L Phase I vs. Phase II

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I understand there are known hg issues with the 2.5's, also if I understand correctly, the issues were more common amongst the Phase I versions and not so much with the Phase II (correct me if I'm wrong so far).

 

I just bought a 2000 Outback Wagon, it's a 2.5L but how do I know if it's a phase 1 or phase 2? Are there any identifying marks? What year did the phase 2's go into affect?

The '00obw are supposed to get the coolant conditioner though for the potential external HG leak, though hopefully they don't have the internal issue with blowing exhaust gas into the coolant.

  • 3 weeks later...

Uhhh. can someone help me out here. I had an overheat, 2000 OBW, at 186k miles the other night. ok, I have a friend who is really really good. he does all kinds of fixes, in fact he just did a 96 2.5 phase I. so I figure I tow it home and we get dirty.

well I took the heads to a machine shop. they looked good, but we took a thousandth off. New gasket kit, from some engine rebuild shop. very reputable shop. put it all back together. same shiite. exhaust in coolant!!!

at this point I thinking load it up, drive it somewhere, and dump it. Hello insurance!

does anyone have experience here?

I mean, crap, I am thinking it looked wayyy worse when we pulled the heads the second time! the first time the fluid showed a bit in #2, and there was an obvious crack bt the cylinder and fluid. you could see charring/

now it is bad on the other side of the block (passengers) both cylinders over there. no visible cracks tho?

could it be the gaskets? were junk?

what gaskets did you use? subaru head gaskets are highly recommended for this application. the engine block or heads could be cracked or the intake manifold gaskets could be leaking. i wouldn't expect the block to be bad unless you ran it hot for an extended period.

 

maybe you could have a machine shop pressure test the heads?

that will be monday!

I had them face the heads b4 re-install. but dude at shop seemed to be against pressure test/ he was a solid older guy. knew his stuff. solid company as well. 65 years. said that unless I ran the crap outta them HOT, they were probably good.

so we decided to return to test heads as well as Question the gaskets Monday.

 

THey looked really thinn compared to the old ones. the impreg part looked to me like paint. where as the old ones were meaty!

 

they came in a valve grind kit.?????

he might not be very familiar with subaru's or other 90's vehicles that came with updated headgaskets? it's best to stick with the Subaru updated gasket on this one. he's right, the heads will likely test fine, but being a second shot i'd try again. are you sure they were leaking from the headgasket and not the coolant ports on the intake gasket. if those were aftermarket (not subaru), they may have been very thin and sucky as well. if those leak, coolant ends up in the cylinders as well.

Ahhh! That could be it. They were def leaking at HG, the crack was evident. But I will check intake ports. Thanks for the info. I have to wait til monday, I'll let you know if that was it.

 

garth

even if it was the gaskets, it's strange that they would let loose that quick. i would not use them on an EJ engine, but aftermarket gaskets should hold up for some length of time at least. check everything carefully and make sure you're torque sequence and numbers on the head bolts are correct.

thanks. I will print all these suggestions out for monday. after the pressure test on heads.

seems odd that the problem got worse. I gotta think it was something we did wrong, there was coolant in all the cylinders, not like the first time when it was obvious in only #2

OE head gaskets are a must for this repair. Did you cook the engine? Also you need to flush/clean the radiator. Antifreeze+ oil+air makes a great glue to clog everything.

 

 

Phase I HG leaked internally, phase II leaked externally. Subaru cleared the problem up sometime in 2003.

 

nipper

what did you mean by "updated Headgaskets"?

is there a new "spec" for the phase II 2.5 HG?

or is the 0.026 still the accepted?

OE head gaskets are a must for this repair. Did you cook the engine? Also you need to flush/clean the radiator. Antifreeze+ oil+air makes a great glue to clog everything.

 

 

Phase I HG leaked internally, phase II leaked externally. Subaru cleared the problem up sometime in 2003.

 

nipper

 

yo Nip, 1 ?, how do I know if the engine is "cooked" ?

it seemed to run pretty smoothly after the rebuild. just still had exhaust gases in the coolant. and when I tore into again, there was a fair amount of coolant in the 1 &3 cylinders

 

g'

If you go to subaru the dealer will sell you the latest version of the HG. Go someplace else they wont sell you the newest untill thier supply is exhausted.

 

Cooked = how long did you drive the car with the engine temp in the hot zone.

 

nipper

maybe 3 minutes. more like less than one minute.

it overheated at night, shut off immediately when I noticed.

I think I caught it right away. the smell didn't even have time to infiltrate the cabin. how would you recommend checking?

I am getting the heads pressure tested monday, but beyond that...?

maybe 3 minutes. more like less than one minute.

it overheated at night, shut off immediately when I noticed.

I think I caught it right away. the smell didn't even have time to infiltrate the cabin. how would you recommend checking?

I am getting the heads pressure tested monday, but beyond that...?

 

Take a straight edge to the decks of the engine. When you cook the engine, you can actually get things hot enough that the cylinder sleeves will move, making it impossible for the HG to ever seal the engine again.

Check both sides, they should be the same.

Also an oil change wouldnt hurt. I am thinking you just got some crummy gaskets. Its rare when one of these cant be fixed, but when it cant its usually because a cylinder sleeve has moved.

 

nipper

Take a straight edge to the decks of the engine. When you cook the engine, you can actually get things hot enough that the cylinder sleeves will move, making it impossible for the HG to ever seal the engine again.

Check both sides, they should be the same.

Also an oil change wouldnt hurt. I am thinking you just got some crummy gaskets. Its rare when one of these cant be fixed, but when it cant its usually because a cylinder sleeve has moved.

 

nipper

 

excellent! Thanks!

that will be first thing tomorrow.

 

What do you think about the situation getting worse? could it be the sleeves moved, but were cool with the old gaskets, and the situation only presented with the new gaskets?

The original gaskets went because of age. HG on any car blowing after 140K is just age. HG's are very difficult to design (that's why every car mfg has some history of blown HG in the 1990's).

Hard to tell as i dont know what you replaced them with.

 

nipper

The original gaskets went because of age. HG on any car blowing after 140K is just age. HG's are very difficult to design (that's why every car mfg has some history of blown HG in the 1990's).

Hard to tell as i dont know what you replaced them with.

 

nipper

I'll post that info Monday so EVERYONE can beware. I left the package at the garage.

 

Thanks again for all your help and knowledge.

I love the car. this is a learning experience for sure.

maybe next time I start with less miles from the gun! I purchased super cheap. jan 06, 140k. 5500$ beautiful coat. so I don't think I am upside down yet!

company pays for everything anyway.

 

garth

APEX! says the stamp. don't knock 'em yet, but......

 

didn't think to check gaskets which were laying with heads waiting to go to machine shop.

do you have CURRENT thickness #s? for phase II

APEX! says the stamp. don't knock 'em yet, but......

 

didn't think to check gaskets which were laying with heads waiting to go to machine shop.

do you have CURRENT thickness #s? for phase II

 

Head gaskets are far more complicated then how thick they are. They are made in multiple parts with multiple layers.

 

Go to the dealer and get a factory set.

 

Apex? Not even felpro?

 

nipper

Car is up and running. The Apex gaskets were crap! I would never attempt this again without OEM parts. I did use an aftermarket radiator, but it is an easier fix if it goes wrong, and I have used them before with great results.

I also ended up replacing :

 

- plugs

- Wires

- Knock sensor

- radiator, pressure cap

- thermostat

- water pump

- timing Belt

- several idler pullers for Tb

 

after the first few hundred miles, I will see how it runs. I was at 27+ highway before.

 

garth

I just had a very long and quite enlightening conversation with the head guy at an independant Subaru shop that does most of the Subaru work in Anchorage. Among many other things, the EJ25 HG issues came up.

 

He is experimenting with using the updated HG's for the phase I (DOHC) EJ25 on the Phase II (SOHC) engines that he has HG issues with. Apparently, the phase II engines use a very thin HG that is easily damaged by normal temperature fluctuations. In fact, Anchorage has the highest occurance of HG failures of anywhere in the world Subaru sells those cars. We think it's because the typical temperature range that the engine experiences during the winter here is much greater than most places.

 

According to this guy, the gaskets match right up, and he's put a couple together that way already...just waiting to see how they hold up. I agree that the thicker, multi-layer-metallic design of the updated phase I gaskets is probably superior and able to handle more abuse. Of course the increased thickness will lower compression very slightly, but we agreed that it is probably an inconsequential difference (anyone know the thicknesses and want to run the numbers?).

He is experimenting with using the updated HG's for the phase I (DOHC) EJ25 on the Phase II (SOHC) engines that he has HG issues with. Apparently, the phase II engines use a very thin HG that is easily damaged by normal temperature fluctuations. In fact, Anchorage has the highest occurance of HG failures of anywhere in the world Subaru sells those cars. We think it's because the typical temperature range that the engine experiences during the winter here is much greater than most places.

 

 

So your telling me NOT to drive up to AK this summer?

 

nipper

So your telling me NOT to drive up to AK this summer?

 

nipper

 

Just leave your car running the whole time:cool: .

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