EJ25 Head Gasket Problem

Subaru has not acknowledged a head gasket problem with the EJ25 2.5 litre H4 engine. However there are several thousand messages related to head gasket failures on the various Subaru message boards.

Two distinct problems are reported as common:

EJ25 DOHC (Phase 1): blown head gaskets, loss of engine compression, and coolant in the oil, or oil and exhaust in the coolant.

EJ25 SOHC (Phase 2): head gasket external coolant leak. Typically a small amount of coolant is leaked at cold temperatures from the rear of the engine. The coolant leaks onto the exhaust where it is vaporized. The coolant vapor produces the typical "sweet" coolant smell inside the vehicle. Once the engine is warm, the leak seals itself. The leak is VERY difficult to detect. There is typically no oil or coolant contamination, nor can the leak be detected by a cooling system pressure test.

It is definitely a problem, but without reliable statistics it is impossible to determine whether 2% or 25% of engines are affected.

One message board thread discussion of the head gasket problem.

More Information at the German Autobild site: check the section "Historie, Schwächen, Kosten" (History, Weaknesses and Costs). It claims that 8% of Subaru Legacy's experience head gasket failure. However this may be a German statistic, not an overall one. Canadian winters are much harder on cars.

Here is a statement from the Autobild site's Engine and Transmission section. Bad english courtesy of Altavista Babelfish German to English translation:

"Sometimes at the machine or other cylinder head gasket blows through ; the double-piston engine beherrbergt their two. That can obviously already happen with less than 50,000 kilometers. No miracle that some the Legacy-2.5-Fahrer in the course of the time had to let a cylinder head gasket replace even several times. This defect over five times more frequent than the capacity-smaller boxer in the Legacy, quite zeitaufwaendige with the repair, meets the 2,5-Liter-Motor."

Autobild site (German)   Babelfish German to (bad!) English translation

Babelfish German to English translation example:

Original:

Die Karosserie gefällt durch Klapper-Armut, sauber verlegte Elektrik und solide Korrosionsvorsorge. Deutliche Rostspuren konnten nur 4,8 Prozent der Aktionsteilnehmer entdecken.

Translated:

The body pleases by rattling poverty, cleanly shifted electrical connection and solid corrosion precaution. Clear rust-pure could discover only 4.8 per cent of the action participants.

Body pleases by rattling poverty??? The translation is usually good enough to provide the reader with the topic of discussion.