Preliminary Work

Information 

The pictures shown in this document may differ from the original.

1. Unscrew and remove all spark plugs.

   > 287020 REMOVING AND INSTALLING SPARK PLUGS

2. Position cylinder to be tested to ignition TDC and remove tool (dead centre finder).
   1. 2.1 The dead centre finder or "cylinder pipe" consists of a glass tube (inspection glass) with a piston -1-  , hose and a rubber cone -2-  .

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Dead centre finder - "cylinder pipe"

   2. 2.2 The rubber taper is pressed onto the spark plug hole. The inspection glass is either held by a helper > Tool setup - dead centre finder  or is secured vertically in a clearly visible position with a magnet.

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Tool setup - dead centre finder

   3. 2.3 If the engine is now turned in direction of rotation on the crankshaft, the piston in the inspection glass is pressed up in the compression cycle > Top piston  in order to go back down immediately upon reaching the TDC. The piston in the inspection glass stays down in overlapping TDC > Bottom piston  .

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Top piston

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Bottom piston