Measure the I.D. of the piston pin bore in both horizontal and vertical directions [Figure 70-90-7].
If the measurement exceeds the allowable limit, replace the piston.
Measure the O.D. of the piston pin (Item 1) [Figure 70-90-8].
Measure the I.D. of the connecting rod small end (Item 2) [Figure 70-90-8].
Calculate the oil clearance. If the clearance exceeds the allowable limit, replace the bushing. If it still exceeds the specifications, replace the piston pin.
To replace the connecting rod small end bushing, make a driver tool as shown in figure [Figure 70-90-9].
Use a press and special driver tool to remove the small end bushing [Figure 70-90-10].
Installation: Clean the small end bushing and bore. Put oil on the bushing and press into the connecting rod until it is flush [Figure 70-90-10].
Install a piston ring into the lower part of the cylinder bore. Measure the ring gap with a feeler gauge [Figure 70-90-11].
If the gap exceeds the allowable limit, replace the ring.
Remove the carbon from the ring grooves. Measure the clearance between the ring and groove with a feeler gauge [Figure 70-90-12].
If the clearance exceeds the allowable limit, replace the ring. If the clearance still exceeds the allowable limit, replace the piston.
