WEICHAI WD10 Service Manual - page 79
Service Manual for WD10 Diesel Engine
69
(5) Adjust opening direction of each ring: The opening direction of first compression ring should
be 30°
to piston pin center line, opening direction of the second compression ring should be 120°
to that of the first compression ring, and opening direction of oil ring should be 120° to both
that of first compression ring and second compression ring, also should be perpendicular to
piston pin center line. As shown in Fig. 4-35.
Piston pin center line (horizontal)
First compression ring
Second compression ring
Oil ring
Fig. 4-35 Schematic diagram for installation of piston rings
(6) Rotate the flywheel with external force until cylinder 1, 6 get to BDC, fit cylinder 1, 6
piston-rod assembly and loose-fit connecting rod bolts. Connecting rod parting surface should
face left side of cylinder block (i.e. engine oil cooler side). The numbered pistons should not be
mixed, install each piston to the corresponding cylinder; connecting rod cap and connecting rod
should be used in pairs, apply clean lubricating oil on connecting rod bolts before assembling.
(7) Tighten connecting rod bolts: Firstly pre-tighten the bolts to 120Nm in symmetry, and then
tighten each bolts for further 90°±5°, in the meantime tighten torque should be up to
170~250Nm. Assemble other piston-rods in the same way.