Head gasket question relevance 2 or 3 hole - TDI Engine -General Info - VWDiesel.net The IDI, TDI, and mTDI source.

• Head gasket question relevance 2 or 3 hole by DieselVanagon on 09 Jan, 2010 22:10
• According to my part supplier the AHU TDI head gaskets variations are identified by holes??. There is a 2 hole version with 1.5mm thickness and a 3 hole version with 1.6mm.
  Where are these identifying holes, how much does it matter to get the right one?
  
  
  
• #1 by fairweather on 10 Jan, 2010 18:35
• You can get 1,2 or 3 holes. It depends on the amount of piston protrusion above the block, The specs are in the Bentley.
  
  Looked it up:
  
  For 1Z/AHU
  .91-1.0 mm  1 hole
  1.01-1.10mm 2 hole
  1.11-1.2mm   3 hole
  
  I used a 25$ digital caliper and confirmed with a micrometer though the mic is overkill for this. Make sure the piston is at absolute TDC.
  
  
• #2 by burn_your_money on 10 Jan, 2010 18:46
• The ID holes are on the front of the engine in front of cylinders #2 and #3. It's a tab sticking out. Usually you can go by what is on there but the proper way is to measure it. Mechanics are lazy and will just swap on a #3 gasket (thickest)
• #3 by DieselVanagon on 13 Jan, 2010 21:19
• Thanks for the advice. I will measure to confirm what I need to order. The tab on mine has one small hole and one oblong.
  
  This website has great pictures of the differnet head gaskets.
  http://www.ipco-inc.com/