Subaru teardown

In December 2005, I bought a 1997 Subaru Outback. The engine ran fine but had bubbles in the coolant indiacting a failing head gasket. This is a short photo journal of the engine repair.

Step 1: Remove engine. Total time: 90 minutes.
One of the exhaust gaskets was showing signs of impending failure.

Right valve cover removed. Everything is clean; evidence of a good maintenence history. Note the drill & tap next to the spark plug hole - a provision for Coil on Plug ignition, not used on this model.
Right head off. No obvious signs of head gasket problems.

Head gasket looks pretty good too. Some chunks of black sealant missing at the bottom edge of #4
Looking at the right head shows green coolant stain on the #4 exhaust valves.

Left head looks ok. For some reason these engines tend to fail on cylinder 4. You can see the difference that valve clearances make on cylinder #3
Intake valves look good. All intake valve clearances were still in spec. 4 of 8 exhaust valves were tight by 1 to 3 thousandths.

Here is what the block deck looks like. Bolts in the bottom of the coolant passages hold the block halves together.
Even after 202k miles, the block still has factory hone marks. Amazing.

Another shot of cylinder wall surface. There is no ridge at all.
Top end disassembly complete. It takes very few tools to get one of these apart. Notable features are the captured washers on the head bolts and factory markings indicating which cam caps go where.

For kicks, I removed the oil pan to have a look at the bottom end. There are a lot of baffles in there. No deposits at all, a good sign
The very stout bottom end of an EJ series Subaru engine. The crankshaft webs are amazingly thin.

I decided to tempt the devil and remove the rod bearing caps that I could reach. The top halves of the bearings are just starting to show copper. I elected to split the block and replace all the bearings.
Crank surface is excellent. Looks like a standard set of bearings will be sufficient. Everything is balanced, blueprinted and laser etched from the factory.

Here is a shot of a piston. The oil control ring is filled with crud and stuck in the groove, although the car did not smoke at all. Note the short piston skirts - I can see way these engines are notorious for piston slap.
Even after 202k miles, the piston ring end gap is still within spec for a brand new engine. Since the engine did not use oil, I will be leaving the rings and cylinder bores alone.

All in all, this engine has held up very well for 202,000 miles.If not for the head gasket problem, this engine would likely have run for another 100k miles without a problem. I would also say that the rod bearings are on the small side for this engine. Given the very compact design, there is not much Subaru could do about that.

I have the full service history for this car. It was treated to conventional "Jiffy Lube" motor oil at 7200 mile intervals on average. Clearly dino oil is good enough to go 200k miles easily with no top end sludge and virtually no wear to the cylinder bores. With the new parts inisde, this engine should be good to go for another 200k.

Step 1: Remove engine. Total time: 90 minutes.	One of the exhaust gaskets was showing signs of impending failure.
Right valve cover removed. Everything is clean; evidence of a good maintenence history. Note the drill & tap next to the spark plug hole - a provision for Coil on Plug ignition, not used on this model.	Right head off. No obvious signs of head gasket problems.
Head gasket looks pretty good too. Some chunks of black sealant missing at the bottom edge of #4	Looking at the right head shows green coolant stain on the #4 exhaust valves.
Left head looks ok. For some reason these engines tend to fail on cylinder 4. You can see the difference that valve clearances make on cylinder #3	Intake valves look good. All intake valve clearances were still in spec. 4 of 8 exhaust valves were tight by 1 to 3 thousandths.
Here is what the block deck looks like. Bolts in the bottom of the coolant passages hold the block halves together.	Even after 202k miles, the block still has factory hone marks. Amazing.
Another shot of cylinder wall surface. There is no ridge at all.	Top end disassembly complete. It takes very few tools to get one of these apart. Notable features are the captured washers on the head bolts and factory markings indicating which cam caps go where.
For kicks, I removed the oil pan to have a look at the bottom end. There are a lot of baffles in there. No deposits at all, a good sign	The very stout bottom end of an EJ series Subaru engine. The crankshaft webs are amazingly thin.
I decided to tempt the devil and remove the rod bearing caps that I could reach. The top halves of the bearings are just starting to show copper. I elected to split the block and replace all the bearings.	Crank surface is excellent. Looks like a standard set of bearings will be sufficient. Everything is balanced, blueprinted and laser etched from the factory.
Here is a shot of a piston. The oil control ring is filled with crud and stuck in the groove, although the car did not smoke at all. Note the short piston skirts - I can see way these engines are notorious for piston slap.	Even after 202k miles, the piston ring end gap is still within spec for a brand new engine. Since the engine did not use oil, I will be leaving the rings and cylinder bores alone.