Assembling Piston And Connecting Rod - Yanmar BY Series Service Manual

ENGINE
2. Clean piston ring grooves using a piston ring
groove cleaning tool. Follow tool manufacturer's
instructions for correct operation.
3. Wash pistons in an appropriate solvent using a
soft-bristled brush.
4. Visually inspect each piston for cracks. Pay
particular attention to the ring lands between
the piston ring grooves.
Figure 5-50
5. Install a new piston ring. See Assembling
Piston and Connecting Rod on page 5-38. Use
a feeler gauge to measure the gap between the
ring and the piston (Figure 5-50). Replace the
piston if not within specification. Repeat with
the second ring.
Note: The oil ring (third groove) cannot be
measured.
6. Repeat steps for each of the cylinders and the
piston rings for that specific cylinder.
5-38
Assembling Piston and Connecting
Rod
1. Clean the piston and rings thoroughly without
damaging the ring grooves.
2. Oil the wrist pin bore and wrist pin before
assembling.
Figure 5-51
3. Check the fit of the wrist pin in the connecting
rod. The wrist pin should pass through the
bushing with little force and not have any
significant play (Figure 5-51).
4. Install one retaining ring in the piston with the
gap in the retaining ring opposite the recess.
Figure 5-52
5. Orient the piston and connecting rod as shown
for assembly (Figure 5-52). The arrow on top of
the piston must point to the right when the
connecting rod identification marks are visible.
BY Service Manual
Pistons and Cylinders