I bought a new 2000 Outback Ltd Edition and replaced the head gaskets at 85,000-miles, just out of warranty. One was leaking externally below the right rear cylinder emitting vapor.
The car now has 135,000 miles and I'm smelling coolant vapor again. While the performance of the engine is good, I wouldn't recommend it based on this defect. With proper design, head gaskets should last at least until the valves need to be ground and the seals replaced. That would be at least 150,000 to 200,000-miles minimum, not a pathetic 50,000 to 85,000-miles.
Stop-leak is a poor substitute for a properly designed engine and head gasket sealing system. I'll keep putting it in until the vapor becomes visible again. Then I'll replace the head gaskets yet again while muttering choice words for the negligent so-and-sos at Subaru who stuck their heads in a dark place and ignored this defect for years. There's no excuse for it.
So, when people say the EJ25 sucks, it deserves a bum rap. No matter how good an engine performs, when it falls apart like this it either leaves you shopping for a new engine, a new car, or a weekend to replace the one when your head was stuck under the hood. This engine is a toy, not a serious piece of equipment for a vehicle that needs to travel long distances without trouble.
Go with the EZ30 H6. It's a better engine.
I've been researching replacing my EJ25 with one of those or perhaps an EG33 out of an SVX with a fried 4EAT transmission that only does FWD anymore (which was another nasty problem caused by stubborn idiocy and the reason why I've chosen manual transmissions). Either project is complicated by substantial amounts of welding or reworking of things like fuel pumps, ECUs, instrumentation, and wiring. But at least then, I can have the satisfaction of applying a creative solution that might impress the ladies.
