Swapping the Engine in My Subaru

Sep 20, 2025·
Ehsan Sharafian
Ehsan Sharafian
· 2 min read
hobbies

Some weekends you recharge in the mountains. Others you spend covered in oil in a parking lot, and honestly, those are just as good.

My Subaru Outback had been fighting me for a while, so one weekend we set up shop in the parking lot and got to work.

Out in the parking lot, first trying to save the original engine

We started out hoping for a modest fix, replacing the valves and valve guides on the original engine to bring it back to life. I pulled the cylinder heads and we went through the valvetrain piece by piece.

Cylinder head off the engine and in my hands, ready to work on the valves

A close look at the valvetrain and camshaft on the bench

But the old engine had other plans. After a lot of work it became clear it was simply done. So we did what any stubborn mechanical engineer would do. We pulled the whole thing and swapped in a fresh engine.

Sitting in the empty engine bay, weighing our options

The bay stripped down, looking at the bellhousing with the engine out

Out with the old, up on the hoist and out of the car.

Lifting the old engine out with the hoist

I did this alongside my great friend and master wrench, and what could have been a frustrating repair turned into one of my favorite weekends of the semester. Engine hoist, hand tools, a cylinder head on the bench, and a lot of laughs. There is something deeply satisfying about understanding a machine well enough to take its heart out and give it a new one.

My great friend and master wrench, with the old engine up on the hoist behind us

A clip from the swap

Watch the full vlog

We filmed the whole weekend. Here is the story from start to finish:

New engine in, hood closed, and back on the road. Not a bad way to spend a weekend outside the lab.

Cars Wrenching Subaru Weekend Project
Ehsan Sharafian
Authors
Ehsan Sharafian
PhD Candidate in Mechanical Engineering
PhD candidate in Mechanical Engineering at the University of Maine. Focused on intelligent wearable systems that combine biomechanics, IMU-based sensing, machine learning, and real-time mobile applications for human movement analysis, gait assessment, activity recognition, and digital health.