Hiya Scotty!
We're planning ahead to replace our nearly 20-year-old Scion xA with either another Toyota or possibly a Subaru. My question is, given proper preventive maintenance, would the Subaru's engine wear out considerably sooner than the Toyota's because of its horizontally-opposed cylinders vs. vertical ones in the Toyota's inline four? I remember this being an issue with (BMW) motorcycles, but was wondering if the same applies to car engines.
Thanks!
I agree with @bruceree on this. Subaru engines aren’t particularly problematic.
The notorious head gasket thing is sorted; Subaru’s don’t have more head gasket failures than other competitors now. Some people have raised concerns that with the horizontal cylinder geometry that fluids can pool along the side of the cylinder chamber and cause problems if they sit for an extended period, but that is more of a theoretical concern than real.
Subaru makes a number of motors, like any other manufacturer, and they all have idiosyncrasies. But general characteristics across the brand:
- Engine reliability is above average
- They are simple, generally easy to work on, and parts are not expensive
- The exception to easy service is spark plugs; the horizontal geometry make the plugs hard to get to
- Drawbacks are: they tend to be louder and get slightly lower mileage than other motors with similar displacement
I never could figure out why Subaru had so many problems with blown head gaskets and engine problems. Porsche didn't have these kind of problems with their 911 boxer engines from 1963 on.
Classic overthinking. They used coated gaskets instead of bare metal. The coatings would fail.
@dad2lm2 - Good point.
One of the biggest benefits of the boxer engine in a Subaru is its lower center of gravity.
In terms of maintenance, I don’t think maintenance is as horrible as an engine out Porsche. But one may need to prop up the engine with a jack to access the spark plugs. At least that’s what my friends with Subie’s tell me.
That’s how some people do it, especially dealers. I’ve been able to do it on my WRX, my daughters Crosstrek, and my mom’s forester using a short wobble extension.
Nice.
No model in particular, just that being a horizontally-opposed engine, gravity would eventually cause rounding-out of the bottom half of the cylinders; over a l-o-n-g time this would cause an air gap between the top of the cylinder wall and the rings.
Boxer engines have been around a very long time and I've never heard of this effect being observed in the field. It's probably so minor that the engine would be otherwise worn out before it becomes a factor. (If gravitational effect on pistons were an issue it would also show up to an extent in V-type, slanted, and radial engines.)
would the Subaru's engine wear out considerably sooner than the Toyota's
Yes. but what models are we talking about?
No model in particular, just that being a horizontally-opposed engine, gravity would eventually cause rounding-out of the bottom half of the cylinders; over a l-o-n-g time this would cause an air gap between the top of the cylinder wall and the rings.
Idk the issue with BMW bikes though a lot of people like Subaru, being a boxer engine doesn't automatically discount it for having more wear over time, I hold the belief that in general German/European vehicles are more for show and go rather than hold til old
Subaru is plenty capable of lasting as long as a Toyota with proper maintenance. Just find out the quirks of the boxer compared to the inline and see if those things are better for you.
1000th post!