Camshaft
The camshaft is a camshaft bearing.
Maximum axial displacement of the camshaft with the tappets removed and bearing caps installed from 1st to 5th, mm: 0.15.
Radial runout of shaft journals, no more than, mm: 0.01.
The camshaft is marked with a blue belt applied between the first and second cams.
The spare parts are supplied as reground camshafts complete with bearings. In this case, the camshaft is marked with a yellow mark.
The camshafts of the "NP" and "DS" engines produced since September 1985 are identical in design. They have the following markings: the letter "H" between the cams of the 1st cylinder; index "026" between cams of the 3rd cylinder; circular mark with a diameter of 34 mm at the base of the cams.
Camshaft journal diameter, mm:
- nominal: 26.00;
- repair size: 25.75.
Valve timing (with a calculated zero clearance between the camshaft cams and adjusting washers and a valve lift of 1 mm)
When the valve timing mechanism is installed correctly, the "O" mark, corresponding to the TDC of the piston of the 1st cylinder on the flywheel, should be aligned with the mark on the clutch housing, and the mark on the toothed pulley of the camshaft should be opposite the mark on the pulley of the intermediate shaft.
Intermediate shaft
The intermediate shaft is driven by a toothed belt from the crankshaft pulley. The intermediate shaft drives the fuel pump, ignition distributor and oil pump.
Timing Belt for Camshaft Drive
Brand and type: Pirelli 121 R 180 or Uniroyal Powergrip 41121.
The belt tension is considered normal if in the middle of the long branch the belt twists no more than 90° with the force of the thumb and index finger.
[The original publication in its entirety is posted on the website: AudiManual.ru]