[brttaft]

The headgaskets have been done twice now, first time was by subaru under warranty at about 30000 then went again at 110000 was replace by mechanic and now they're blown again. I recently discovered blowby as well. I'm thinking of doing it myself, since I don't trust mechanics, plus my dads a mechanic. But being my first time what else should I probably replace while its open. We have another car I can use so time isn't an issue but I want it done right. I love this car and plan on using it into the 300k range.

 

[JohnnyPheonix]

My motor went south at around 161k with a bad rod bearing. I ended up doing a full tear-down and rebuild. Cost was a bit north of $1k for parts as the crankshaft was toast. I used all factory parts for the rebuild except for the bearings, which were Cosworth.

Before ordering ANYTHING, pull the motor, open it up, and inspect it all. It will take you a bit longer, but no sense in ordering something you don't need or finding out you need oversized pistons, rings, bearings, etc. Have a shop clean the block. If you remove the oil passage bolts (I did) note that the crush washers are NOT in the factory gasket set and will need to be ordered separately, along with the camshaft end caps (rear seals). I also did a valve job on the heads with new seals and retainers, which are in the gasket set. Since my cylinders were in good shape, I did a light hone with a bottle-brush hone for the new rings.

So anyway, for assembly I installed the following new parts:

Crankshaft
Connecting rod
Main bearings
Rod bearings
Piston rings
Gasket set, (almost) complete (Subaru)

Overall, I wouldn't rate the job as super difficult, just make sure you have access to the factory service manual and read the relevant sections beforehand so you can acquire any special tools (14mm hex bit, piston pin extractor, etc) or ask questions if something doesn't make sense. For pulling the piston pins, I made a puller out of a long bolt and ground off the head to make sort of a cam and it worked great. Coming up with an on-the-fly tool for removing those was probably the most difficult part. Second problem was the screws holding the oil/air separator cover were frozen. I had to drill two of them out, but get a impact grade P3 driver bit and use a drill and they come right out. I didn't have one for removing the cover, but I DID have one for taking the oil pump apart and it made it a breeze. Note that you may not have a problem here because Subaru made a design change to hex head screws around '03, but P3's are in the oil pump. When putting everything back together, use plenty of engine assembly lube on moving parts (duh), but apply the "fluid packing" sparingly. There's a drain channel at the rear main seal and you want the be sure none gets into it. I used the Fugibond stuff (Subaru #004403007), but others have used ultra grey with good results.

I've got around 2k on the motor so far and it runs great. One thing it doesn't do as much is search for gears when climbing a grade, and it seems to shift better. Other things I highly recommend for this generation of Outback is the '06 Baja Turbo suspension mod. For me, it made it the car Subaru SHOULD have built.

 

[burnout8488]

Replace with the MLS (Multi Layer Steel) all steel gaskets from Subaru, or use the Fel-Pro MLS gasket kit. Rockauto probably has this kit the cheapest.

Your mechanic probably used the standard, faulty gaskets. Subaru definitely did when they first replaced them at 30,000.

 

[brttaft]

The engine is out, a lot more nerve racking than I thought, thankfully it only lasted a few minutes. Torque converter was the most difficult than anything I forgot to make sure it stayed sitting in the transmission, but it only came out a little and i was able to slide it back before anything happened. I will probably take off the heads and then take it all to a machine shop and have them rebuild the short block and check heads then I will reassemble with new gaskets from Subaru. I'm really glad there are many on here who have done this before otherwise I'd be lost...

 

[susiemk]

If the engine was running fine there is not really any need to rebuild the shortblock, just follow the MLS HG advice given above!

I used 2004 STi HG's (MLS + same cost as the defective OEM HGs @ subaruonlineparts.com) on my ej251 no machine shop for any of the parts as the car never overheated when I did this job last year.

The job was easier than expected with the following parts changed - HGs, rear main / cam / crank seals, new timing belt / tensioner / idlers, Exedy LW flywheel / Exedy OEM replacement clutch kit (pilot bearing / TO bearing / PP+disc) - only part I screwed up on was not resealing the oil-pump (thought the oil was from the leaking HG so I literally have a drop of oil on the bottom of the oil-pump every time I look at it (3000 miles for oil change) no drips on the floor or around the engine)- so I'll reseal or put a new oil pump on the car in the next few weeks...

 

[brttaft]

There is a problem with the engine. The piston ring is broken. It runs just fine, other than exhaust blowing past the piston into the crankcase. Id rather fix it before it causes problems like engine sludge or anything else it can.