SKU: PFM66781
UPC: 037995667819
MPN: 66781
The PROFORM Valve Lash Wrench with 5/8in End is a precision diagnostic and adjustment tool designed for engine builders, mechanics, and serious enthusiasts performing valve lash checks and adjustments on overhead-valve and push-rod engine platforms. Proper valve lash—the clearance between the rocker arm and valve stem—is critical for optimal engine performance and longevity. This specialized wrench eliminates guesswork during setup, ensuring your valvetrain operates within manufacturer specifications.
The 5/8-inch end accommodates the adjustment nut on common valve covers and rocker arm assemblies, providing a secure grip without rounding fasteners—a frequent issue with undersized or improvised tools. PROFORM's design engineers offset the wrench head and handle geometry to allow unobstructed access in tight engine compartments where standard open-end wrenches bind or slip. The compact 10.5-inch overall length balances leverage and maneuverability, while the 0.8-pound weight reduces hand fatigue during extended valve lash procedures.
This wrench is indispensable for street and competition engines—from classic muscle cars and hot rods to modern crate-engine builds and vintage marine applications. Whether you're dialing in a newly rebuilt engine or performing routine maintenance, this tool ensures precision and reliability. Its hardened steel and chrome-plated construction resists corrosion and withstands the repeated torque cycles required during baseline adjustments and tuning sessions.
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