043-109-451HD VW Hardened Valve Adjustment Screw - Beetle, Bus, Ghia

Hardened Valve Adjustment Screw – 043-109-451HD

The 043-109-451HD is a heavy-duty valve adjustment screw designed for the rocker arm assembly of air-cooled Volkswagen engines. This screw is the primary point of contact between the rocker arm and the valve stem, allowing for the precise setting of "valve lash" or clearance. Proper adjustment is critical for engine health, as it ensures the valves open and close fully while accounting for metal expansion during high-temperature operation.

This "HD" version is specifically hardened to withstand the constant high-frequency hammering against the valve stem without mushrooming or losing its thread integrity. Featuring a standard 8x1.0mm thread, these screws are a direct replacement for factory hardware and are essential for maintaining a quiet, efficient valvetrain in both stock and mild performance builds.

Detailed Vehicle Compatibility

Porsche 914:

• 1970, 1971, 1972, 1973

VW Beetle:

• 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977

VW Super Beetle:

• 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979

VW Karmann Ghia:

• 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974

VW Type 2 (Bus):

• 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973

VW Type 3:

• 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973

VW Thing:

• 1973, 1974

VW 411:

• 1971, 1972

VW 412:

• 1973

Product Highlights & Features

• High-Strength Hardening: Treated for maximum durability to prevent the contact surface from wearing unevenly or "pitting" over time.

• Precision Threads: Standard 8x1.0mm pitch ensures a smooth, accurate adjustment that won't vibrate loose when properly locked.

• Sold Individually: Allows for the replacement of a single damaged screw, though 8 are required for a full engine refresh.

• Universal Fitment: Compatible with all Type 1 based rocker arms from the early 36hp engines through late-model 1600cc fuel-injected units.

Technical Specifications

• Part Number: 043-109-451HD

• Thread Size: 8mm x 1.0

• Quantity Per Engine: 8 (Sold Individually)

• Material: Hardened Steel Alloy

Installation & Maintenance Tips

• Standard Setting: For most stock air-cooled engines, the valve lash should be set to .006 inches (.15mm) while the engine is completely cold.

• Check the Nut: Always inspect the locking nut when replacing the screw. If the nut is rounded or the threads are stretched, it can cause the valve clearance to change during operation.

• Surface Inspection: When adjusting valves, check the tip of the screw for any signs of pitting. A pitted screw will give a false reading on a feeler gauge, usually resulting in a noisy "clatter."

• Oil the Threads: Apply a small drop of engine oil to the threads before installation to ensure the screw turns freely during the adjustment process.

043109451HD