Allen Head and Cheesehead Bolt Removal

Overview

This procedure explains how to remove Allen head and Cheesehead bolts from the Porsche 944 S / S2’s 16v engine. These bolts can be tough to remove because the steel threads often bond to the aluminum engine components, making them prone to stripping. This guide shares a simple technique to “wake up” the bolts and remove them without damage, which is especially useful for DIY enthusiasts working on the S / S2’s engine.

Pink and blue text represents links to additional resources, tools, parts, and partner websites.

Tools Required

• Punch (small, suitable for tapping bolt heads)
• Socket extension (optional alternative to punch)
• Hammer
• Allen head tool (size depends on bolt; typically 6mm or 8mm for S2 engine bolts)
• Cheesehead socket (size depends on bolt; typically 10mm or 13mm for S2 engine bolts)
• Wrench (to turn the Allen tool or Cheesehead socket)

Step-by-Step Procedure

Step 1: Prepare the Bolt Area

1. Locate the Allen head or Cheesehead bolt on the Porsche 944 S / S2’s 16v engine that needs removal.
2. Clear any debris or dirt around the bolt head to ensure a clean working area.

Step 2: Tap the Bolt Head

3. Use a punch or a socket extension and a hammer to gently tap around the outside edge of the bolt head. This helps break the bond between the steel bolt threads and the aluminum engine.
4. For Allen head bolts, also tap lightly inside the Allen head opening with the punch and hammer to further loosen it.

Step 3: Remove the Bolt

5. Insert the correct size Allen head tool or Cheesehead socket straight into the bolt head. For the S / S2’s 16v engine, typical sizes are 6mm or 8mm for Allen bolts and 10mm or 13mm for Cheesehead bolts.
6. Hold the tool firmly with one hand to keep it straight and aligned in the bolt head.
7. Use your other hand to turn the wrench attached to the tool counterclockwise to loosen the bolt.
8. If the bolt resists, stop turning, remove the tool, and repeat Step 2 to tap the bolt head again before trying once more.
9. Once the bolt starts to turn, continue unscrewing it until it’s fully removed.

Post Procedure Checklist

• Inspect the removed bolt for signs of stripping or damage. Replace if necessary.
• Check the threads in the aluminum engine component for damage. If damaged, consider using a thread repair kit.
• Ensure no debris falls into the engine during removal.

Sources

• Clark’s Garage
• Pelican Parts
• Porsche 944 Workshop Manual, Volume 1
• Youtube