A worn or damaged flywheel can create numerous drivability symptoms and result in clutch wear and premature failure. Like disc brake rotors, flywheels tend to be relatively durable, but improper clutch usage or damaged clutch friction material can cause surface defects. These defects typically take the form of hot spots, grooves, or uneven surface quality.
Because of the extensive labor required to replace a clutch, it's always a good idea to examine the flywheel when replacing one. However, determining the best course of action can be trickier. Should you reuse your existing flywheel or replace it with a new one?
Why Should You Reuse Your Flywheel?
The most straightforward reason to reuse an existing flywheel is cost. Replacing a clutch isn't cheap, and there's no sense in spending more money to unnecessarily replace parts. As long as your existing flywheel is still usable, there's little benefit to installing a new one. Resurfacing (or "turning") an old flywheel is typically good enough to restore it to like-new condition.
Another reasonable justification is quality. The factory flywheel in your vehicle may be superior to aftermarket alternatives, and manufacturer or OEM parts may either be cost-prohibitive or completely unavailable. For example, finding brand-new factory flywheels for classic cars or even older work trucks isn't always easy.
By reusing your existing flywheel, you'll ensure that you don't need to worry about balance issues or other quality problems that may exist with aftermarket alternatives. You also won't have to worry about extra labor costs due to poor-fitting, low-quality parts. These advantages alone can make resurfacing and reusing your existing flywheel an attractive option, even if cost isn't a consideration.
Should You Resurface Your Flywheel?
If you know you want to reuse your existing flywheel, should you automatically resurface? The answer to that question can be somewhat more complex. In general, you should carefully examine your flywheel for defects, imperfects, and warping. If you aren't comfortable making these judgments, it's best to take the part to an experienced auto shop for a closer examination.
In general, you should never reuse your flywheel without at least ensuring that the surface is in good shape. In most cases, you'll find that resurfacing the wheel makes sense, even if you only remove a minimal amount of material. Resurfacing helps keep the surface clean and even, making the new clutch bedding process go more smoothly and ensuring your new clutch doesn't wear out too quickly.
When in doubt, always rely on a professional to carefully check your flywheel for significant surface defects. Reinstalling a flywheel with these problems is likely to be far more costly over the long run than the relatively low price of resurfacing. For more information, contact a flywheel resurfacing service such as P&O Brake.