Weifang 495 - Checking the Piston Ring Gap

F. Should'a piston or a corlnectirlg ro-d l)e renewed ,the weight
differences among the fout pisto,n connecting rod assem'b1ies
should be less than o. 05 kg.
G. Anew piston ring shouJd be able to slide freely along th~e
ring ,groove due to its own weight- The ring gap should be mea- '.
sured with a feeler while the ring is placed into the liner (Fig. 12).
If it doesn't conform ,,~ith tIle specified value (for the first com-
pression ring is 0, 30-':- (J. 45 mm. for the others are o. 25 - o. 40
mm) ,it can be filed with a fine file.
Fig. 12 Checking the piston ring gap
While installing piston rings, pa,y attention to tllat the first
compression ring is chrome plated, the threeconlpression ring, gaps
should be offset 120
0
one after the other in sequence, the chamfers
of the two oil rings should face to the I)iston top ,the two oil ring
gaps should be offset 180
0
one after another and the' positions of all
gaps should not be on the center line of the 'piston pIn bore'as
shown in the Fig. 13 an(j Fig. 14.
If the Duaflex oil ring is used, the backing expander ( )
should he fitted firstly into the ring groo'v'evvith its ends just In
to,UC}l ,with each other but without overlapI)tng, ,then slip on the
38