SAAB WIS ONLINE

Pistons

Pistons

General data

Mean piston speed at 5000 rpm m/s 16,3
Different makes of piston must not be fitted in the same engine.


Piston types


Classification of pistons and cylinder bores

The piston classification is stamped on the piston crown roof. Piston classifications are:

Classification codes
8 mm 83,975 - 83,985
99 mm 83,915 - 83,925
00 mm 83,925 - 83,935
01 mm 83,935 - 83,945
02 mm 83,945 - 83,955


The cylinder classification is stamped on the cylinder face and is specified for each cylinder. The cylinder classifications are:

Classification codes
8 mm 83,975-83,985
99 mm 83,985-83,995
00 mm 83,995-84,005
01 mm 84,005-84,015
02 mm 84,015-84,025


Piston rings


Upper compression ring Lower compression ring Oil scraper ring
Thickness mm 2,00 1,75 3,00
Side clearance in groove mm 0,02-0,04 0,02-0,04 0,01-0,03
Working gap in cylinder mm 0,30-0,50 0,30-0,50 0,40-1,40


They can all occur in the same cylinder block.

The piston ring working gaps must be displaced 120° to each other.

Gudgeon pins

Diameter mm 29
Length mm 68
Gudgeon pin in relation to connecting rod mm Floating bearing