The Hidden Costs of Replacing a Subaru Head Gasket

Replacing a head gasket in an older Subaru can feel like falling down a mechanical rabbit hole. Whether you’re fixing a blown gasket or upgrading your EJ engine for more power, the true costs often go far beyond the head gasket itself. From brittle hoses to unreliable timing components, here’s a breakdown of the often-overlooked expenses you’ll face when tackling this job.

The Head Gasket: The Infamous Culprit

The head gasket is the bane of Subaru owners and the reason why many EJ engines end up on the operating table. While it’s tempting to grab a bargain aftermarket gasket, that choice can backfire. A cheap gasket often means you’ll be tearing the engine apart again in a few thousand miles. Subaru’s OEM gasket kits, priced at around $315, are a solid investment. These kits include nearly everything needed for the rebuild, ensuring quality and reliability.

But there’s more. For those seeking enhanced performance or longevity, ARP head studs are a must. Unlike stock head bolts, ARP studs offer superior clamping force, higher tensile strength, and reusability. While they cost between $200 and $500, they are a “buy once, cry once” solution that will protect your investment.

Timing Components: A Silent Threat

Your engine’s timing system ensures the synchronization of the crankshaft and camshaft. If it fails, the consequences can be catastrophic. Older Subarus often have timing components that are far past their prime. Gates kits were once a go-to, but reports of failing oil seals, leaking tensioners, and brittle belts have made them less reliable. A better alternative is to invest in high-quality Japanese timing components from brands like Company 23.

Additionally, many older Subarus still run plastic OEM cam gears. These gears, weakened by years of heat cycles, can shatter at high RPMs. Upgrading to billet aluminum cam gears from brands like Roger Clark Motorsports offers a lifetime solution to this problem.

Heat and Time: Hoses and Clutch Forks

Subaru’s engine bays are notorious for heat buildup, which wreaks havoc on rubber components. Coolant, vacuum, and other hoses become brittle and can crumble in your hands during disassembly. Replacing all hoses while the engine is out might seem tedious, but it’s a small price to pay compared to the headaches caused by a failure later.

Another vulnerable part is the clutch fork. Subaru’s OEM clutch forks are prone to cracking, especially in high-performance builds. For builds staying close to stock, a new OEM fork should suffice. But for more power-intensive setups, an upgraded fork, such as those from Beish, is essential to prevent catastrophic failure.

Labor Costs: A Pricey Commitment

Labor is one of the biggest costs associated with a head gasket job. Pulling and replacing the gasket on an EJ engine can take anywhere from 20 to 40 hours. With shop rates averaging $150 per hour, labor alone can range from $3,000 to $6,000. Factor in the cost of parts, and a complete head gasket replacement can easily climb to $4,000–$7,000.

If you’re tackling the project yourself, prepare for a time-intensive process. Broken bolts, unexpected part replacements, and delays for specialized tools or machine shop services can stretch the project timeline significantly. In many cases, having access to an experienced Subaru mechanic can make all the difference, saving you hours of frustration and ensuring nothing gets overlooked.

Machining and Additional Work

For engines with higher mileage, it’s often necessary to machine the heads to ensure a proper seal. This adds another layer of cost and complexity, especially with the potential delays from machine shops. Checking and adjusting valve clearances is another task that’s easy to skip but critical for long-term reliability. In some cases, a complete engine refresh might be necessary, especially for track or performance builds.

Why It’s Worth It

Despite the hidden costs, replacing a Subaru head gasket is an opportunity to address long-standing issues and build an engine that’s stronger than ever. From upgraded timing components to reinforced head studs, every investment adds reliability and longevity to your EJ engine. While the process can be expensive and time-consuming, the results—whether it’s a reliable daily driver or a track-ready machine—are worth the effort.

To see this transformation in action and learn more about tackling Subaru head gasket replacements, watch the full video and more on Nolan Marketti’s YouTube channel. For behind-the-scenes updates and more automotive goodness, connect with Nolan on Instagram, Twitter, and join the community on Discord.