I have a Forester that I bought recently. It is a 99 S with the 2.5 single cam. The headgaskets are leaking oil and the bottom and I see some coolant as well on the passenger side.
Can I just pull the engine and slap new gaskets on or is it likely that the heads need to be sent to the machine shop? It runs and drives fine, no mixing of the coolant and oil.
I did the head gaskets on my 01 legacy with similar symptoms without having any work done at the machine shop. You can do the job in the car with some creative rocking and twisting of things. If you take the engine out and its an automatic, there's some kind of critical alignment to pay attention to when you reinstall. Woody has a thread, and it was fixed with something called a Fornetti tool. Just an FYI. Its a pretty straightforward job otherwise.
Pulling the engine is generally considered easier/worth the extra effort. My local Subaguru doesn't have anything machined, just replaces the gaskets (he told me he uses Stars brand). Be sure to do the gaskets on the back/clutch side of the engine also. There is some plate back there that can weep oil when it gets old.
Pull the motor. It is pretty easy to remove, and makes the job MUCH easier. Check the heads for flatness, I think .002 max is the limit. Also, try to find a shop that the dealer uses. There is a surface finish spec that many shops will not meet.
A 99 should be a twin cam, at least in my legacies.
Other things I learned:
The old head bolts are fine. What the dealer does. Oil the threads and washers before torque
Do the timing belt, water pump and idlers while you are in there. Plugs too if you want to keep it.
Don't know what the alignment issue is. Auto has 4 bolts that are tough but not impossible with the manifold on.
The trans has to be lifted slightly to get the bottom engine studs clear. Some use a jack under the trans, I bought a small turnbuckle to replace the trans brace dogbone.
Just went through this on our '08 Outback. I've since talked to a few people that have just had shops slap new head gaskets on with the engine in the car. Every one of them says their Subaru goes thru oil at an alarming rate.
mikeatrpi said:If you take the engine out and its an automatic, there's some kind of critical alignment to pay attention to when you reinstall.
I'm not sure what this is about. The engine install was very easy for me. I think the only thing that could cause problems is if the torque converter comes unseated when you pull the engine. So long as you check it and don't force things back together I don't see that causing any problems.
I have done HGs in a SOHC legacy with the engine in the car, but it's really tight. I had to use a ratchet strap to pull the engine to one side of the bay so I could remove the opposite head. If there's less distance between the frame rails in a Forester than legacy it would probably not work.
The engine comes out so easily I would just pull it. The last one I did (a DOHC legacy) I had the engine on a stand in under a hour. You can get to the starter and all but the lower 2 bellhousing bolts from above very easily. Also, don't bother removing the intake manifold, just pull the 8 bolts that secure the manifold to the heads and slide the heads out from under the manifold.
Unbolt the power steering pump and AC compressor and swing them away from the engine in the bay. That way you won't have to disconnect the associated hoses/lines.
The SOHC HG job is nice since you don't have to pull the cams to access the head bolts.
All the ones I have had apart did not need any machine work on the heads. They are short and not prone to warping. a 12" Starrett machinist's straight edge is great for inspection.
porschenut said:Pull the motor. It is pretty easy to remove, and makes the job MUCH easier. Check the heads for flatness, I think .002 max is the limit. Also, try to find a shop that the dealer uses. There is a surface finish spec that many shops will not meet.
A 99 should be a twin cam, at least in my legacies.
Other things I learned:
The old head bolts are fine. What the dealer does. Oil the threads and washers before torque
Do the timing belt, water pump and idlers while you are in there. Plugs too if you want to keep it.
Don't know what the alignment issue is. Auto has 4 bolts that are tough but not impossible with the manifold on.
The trans has to be lifted slightly to get the bottom engine studs clear. Some use a jack under the trans, I bought a small turnbuckle to replace the trans brace dogbone.
99 Foresters went SOHC but Legacy's stayed with the DOHC.
I did actually have to do some pretty significant block sanding on my heads because the previous head gasket mechanic used a really aggressive abrasive rotary pad randomly over the head that left deep scratches. My engine is leak free now though!
ZB says it's easy in chassis but pulling the engine is really easy, and also makes it easy to reseal the oil pan which is also leaking.
I'm definitely pulling the engine if I decide to do it.
enginenerd said:mikeatrpi said:If you take the engine out and its an automatic, there's some kind of critical alignment to pay attention to when you reinstall.
I'm not sure what this is about. The engine install was very easy for me. I think the only thing that could cause problems is if the torque converter comes unseated when you pull the engine. So long as you check it and don't force things back together I don't see that causing any problems.
Yup torque converter; I found the thread: https://grassrootsmotorsports.com/forum/grm/the-dreaded-subaru-torque-converter-situation/92399/page1/
In reply to mikeatrpi :
It's not a Subaru specific problem, anything with an automatic can enjoy the converter unseating from the pump. And it's either a rite of passage or a sign of being a complete bonehead if you wreck a pump bu just jamming the engine and trans together, depending on how much you accept failure in life.
Eh man, I didn't do it! I did mine in the car!! Talk about a rite of passage. 
Moral of the story: buy vehicles with three pedals, as God himself intended
You'll need to log in to post.
