shattered cam sprocket

[lichen]

Here's the story. I hear a squalling bearing as I'm travelling 65mph. I slow to 55, noise stops. One mile later, the engine dies.

Tow home, open timing case, lo and behold, the lower passenger-side cam sprocket is just-- gone! It's shattered into five pieces.

How is this possible?

[lichen]

Found it. Should have known. The valve train on that side is damaged. Cam won't turn. Sorry, guys, I got it!

[Fairtax4me]

Oil starvation.

Squealing was probably the cam eating the bearing journals in the cylinder head.

 

Passenger cylinder head is the last in line to get oil. Either the oil got very low, or something got sucked into the oil passage and caused an obstruction that prevented oil from getting to the head.

[lichen]

Oil level was good...

[idosubaru]

Oil level was good...

 

current oil level only verifies that failure wasn't caused by low oil since the last oil change. the issue may have been initiated at any time in the history of the vehicle.  As he said - usually it's:

 

1.  prior low oil conditions at any time since leaving the dealer lot.

2.  prior overheating (headgasket) compromising the localized material/lubrication properties at the site of failure.

[idosubaru]

some options:

 

1.  used set of heads

2.  EJ22 swap (you don't say but I'm guessing this is a 1998 forester so this would be an easy and great option).  

 

my preference would be to EJ22 swap it. 

used EJ22, new timing kit, spark plugs, wires, valve cover gaskets, reseal separator plate, and water pump and drive it another 100,000 miles...or whatever the equivalent to that is in Hawaii.

then sell your old EJ25 block if the market in Hawaii allows it.