Waterboxer Head Stud Kit

This replacement cylinder head stud kit is designed for all petrol Waterboxer engines in 1900cc and 2100cc sizes fitted to VW Type 25 / T3 buses. Supplying a complete set of 16 studs, this kit is ideal for engine rebuilds, head reseals, or replacing tired, corroded, or stretched original fasteners.

Correct head stud clamping is critical on Waterboxer engines due to the combined demands of combustion pressure and coolant sealing around the heads. Replacing studs during a rebuild helps ensure even torque, correct sealing, and long-term reliability.

What this kit does (and why it matters)

Cylinder head studs provide the clamping force that secures the cylinder heads to the crankcase and barrels. On Waterboxer engines, worn or corroded studs can cause:

• Uneven head torque

• Coolant or compression leaks

• Poor sealing at the head and water jacket area

• Repeat strip-downs and costly repairs

This complete kit restores the correct stud lengths and thread specifications so the heads clamp down evenly and remain stable through repeated heat cycles.

How it works

Each stud threads into the crankcase at one end and accepts a nut at the other, allowing precise torque to be applied during assembly. The different stud lengths are used in specific positions around the engine to ensure correct clamping geometry and load distribution across both cylinder heads.

By replacing all studs as a matched set, you ensure consistent stretch and holding force across the entire engine.

Kit contents

Supplied as a complete engine set:

• 16 x cylinder head studs total

  • 8 x 222mm

  • 4 x 191mm

  • 4 x 175mm

• Thread size: M12 one end / M10 the other

Everything required to secure both cylinder heads on one Waterboxer engine.

Engine compatibility

Suitable for water-cooled petrol Waterboxer engines:

• 1.9 WBX

• 2.1 WBX

Applications:

• VW Type 25 / T3: 1983–1992

Helpful fitting notes

• Fits both sides of the engine.

• Always check crankcase threads before installation.

• Follow the factory tightening sequence and torque stages.

• Best installed during a head reseal or full engine rebuild.

Parts you may also need (recommended)

When replacing head studs, it’s sensible to also consider:

• Cylinder head gasket / sealing kits

• Water jacket seals and correct sealant

• Head nuts and washers

• Pushrod tube seals

• Full engine gasket set if rebuilding