All In: High Mileage 2.5 SOHC Head Gasket Questions

[hohieu]

99 Forester, 172.5K miles

I bit the bullet and bought some KYB struts, mounts, and related parts so as the title suggests, I'm all in for the long haul.  I'll drive this thing until the rear quarter panels rust away.

 

I replaced the clutch and ball joints about 5K miles ago so the next big repairs on the horizon are the timing belt and head gaskets.  The car has the original head gaskets  - still no coolant or oil seepage, let alone leaks.  Assuming they're still holding at the next timing belt change, should I preemptively replace them? 

Edited March 30, 2013 by hohieu

[shotgun_Willie]

Hard to say, mine went at 150,000 but I've heard of them lasting way longer than that. It's a lot of money to do them preemptively but it would be tempting if you could get a good deal doing everything at the same time.

[ocei77]

99 Forester has the 2.5SOHC and as such the HG's will leak externally in this series.

SOA's "fix" was their "conditioner" (read stop leak).

Will last an indeterminate mileage n this condition. Just watch coolant levels and signs of seepage.

 

Unless you have nothing "better" to do, I'd leave it alone.

 

I'm retired, so when I pull an engine I tend to do everything, for I have nothing but time and little sense.

 

O.

[987687]

FWIW I bought my outback with 174k miles and blown headgaskets.

How do the gaskets look from the crack between the head and the block?

Mine looked like this, if it looks like this it's probably tired.

 

[hohieu]

From the photo, it looks like the composite coating is has separated from the metal.  Mine looked more or less intact the last time I was under the car.

 

I've been running the SOA goop in my cooling system since I purchased the car at 72K miles.  When pulled the trans to do the clutch, I sealed the back of the engine.

 

It's been mentioned that these engines can be nursed along indefinitely even with an external leak.  I guess I'm just wondering if any 2.5 Phase II engines have made it past the 300K-mile mark on original head gaskets.  I understand that mileage isn't necessary the best barometer but since there's no gauge that tracks the number of heat cycles, it's the only measure we have. 

Edited April 1, 2013 by hohieu

[987687]

That picture is the top of the engine under the intake manifold (removed in that pic). The bottom was covered in goop...

 

It's really something that's up to you, if it was me, I'd leave it alone. There are ample signs of headgasket failure LONG before it's a problem, and as you said, you can run a very long time with a bad gasket just keeping on top of coolant and oil levels.

[idosubaru]

99 Forester, 172.5K miles

I bit the bullet and bought some KYB struts, mounts, and related parts so as the title suggests, I'm all in for the long haul.  I'll drive this thing until the rear quarter panels rust away.

 

I replaced the clutch and ball joints about 5K miles ago so the next big repairs on the horizon are the timing belt and head gaskets.  The car has the original head gaskets  - still no coolant or oil seepage, let alone leaks.  Assuming they're still holding at the next timing belt change, should I preemptively replace them? 

 

For your EJ25 (not all Ej25's), preemptively replacing them is almost pointless for a variety of reasons:

1.  they don't always leak

2. when this particular variety EJ25 starts leaking it begins really slow seeping externally, causes zero issues, no risk, and you can drive them 50,000 miles leaking...you'll have plenty of time to repair them, preemptively repairing them buys you nothing except extra work that may have never been needed.

3. they may have already been replaced - though you sound confident they're original

 

what i would rather focus on is:

1. have they ever been replaced before?  you seem convinced they're original so that's answered.

2.  replace the coolant and add the coolant conditioner.   they leak often but they also make 250,000+ miles without replacement

3.  replace the timing belts with a complete timing belt kit - all new pulleys and tensioner, ebay has great priced kits, many here prefer theimportexperts though their prices are higher now than they used to be.  with a timing belt replace the cam seals, reseal the oil pump, tigthen the rear oil pump backing plate screws, and replace the water pump.  be sure to use a Subaru water pump gasket (aftermarkets are a joke) and Subaru or XACTA thermostat.

 

if you do replace the headgaskets, resurface the heads and use the EJ25 Turbo headgaskets, otherwise you're just installing the same headgaskets prone to fail to begin with.  the turbo gaskets don't fail.

 

if it was a different EJ25 then preemptive is a great option, some have significant issues with reliability and extensive damage if they blow...not so with yours.

when the clutch was done was the perfect time to do them, the engine/trans already had to come out of the vehicle, saving much of the labor.  but again...not a big deal on yours so move right along.

 

timing belts are super easy on that car, no need to time those with headgaskets.

Edited March 31, 2013 by grossgary

[hohieu]

Alright, it seems the opinions of my respected forum members are unanimous.  I'll just focus on all the things mentioned by Gary, and agree with his reasoning, especially now as my wife no longer uses this car as her daily driver (I get all the hand me downs).  The head gaskets are definitely original -- I bought the car from the original owner.  Thanks to the info. on this forum, I did all the things you mentioned at the 1st timing belt service.  Moving right along, I can satisfy my curiosity about just how far the head gaskets can go on this car.

 

I must add that coming from Toyotas and Hondas, I was a bit skeptical when I first purchased this car in 2004, but it has been rock solid.  SOA resloved the the rear wheel bearing issues when they updated them to tapered roller bearings, and beyond standard maintenance, I've had to replace nothing out of the ordinary beyond wear items such as suspension parts, CV boots, tires, brakes, and a knock sensor.

Edited April 1, 2013 by hohieu

[ocei77]

From your photo I would keep an eye on that water bypass pipe. It has a tendency to rust through at the T which goes to the TB.

 

O.

[987687]

From your photo I would keep an eye on that water bypass pipe. It has a tendency to rust through at the T which goes to the TB.

 

O.

I took it off, wire wheeled down the rust and hit it with some POR15, so hopefully it doesn't rust out. I've had to replace these before, and it's not fun.

[idosubaru]

 I've had to replace nothing out of the ordinary beyond wear items such as suspension parts, CV boots, tires, brakes, and a knock sensor.

it's a solid platform.  headgaskets are the only major issue, they easily make high miles. good luck!