1.6.1 Connecting Rod
DETROIT DIESEL 53
Fig. 3 - Magnetic Particle Inspection Limits for Connecting Rod
Clean the connecting rod and piston pin with fuel oil. and dry them with compressed air. Blow compressed. air through
the drilled oil passage in the connecting rod to be sure the orifice, oil passage and spray holes are not clogged..
Check the connecting rod for cracks (Fig. 3) by the magnetic particle method outlined in Section !.3.under Crankshaft
If a new service connecting rod is required, stamp the cylinder number on the connecting rod and cap (refer to Section
NOTE: Clean the rust preventive from a service replacement connecting rod and
blow compressed air through the drilled oil passage to be sure the orifice, oil
passage and spray holes are not clogged. Also make sure the split line (cap to rod)
is thoroughly cleaned to avoid trapped contaminants from adversely affecting
bearing shell "crush"..
Check the connecting rod bushings for indications of scoring, overheating or other damage. Bushings that have
overheated may become loose and creep together, thus blocking off the lubricating oil to the piston pin, bushings and
spray nozzle. Inspect the piston pin for signs of fretting. When re-.using a piston pin, the highly polished and lapped
surface of the pin must not in any way be refinished. Polishing or refinishing the piston pin is not recommended as it
could result in very rapid bushing wear..
Since it is subjected to downward loading only, free movement of the piston pin is desired to secure perfect alignment
and uniform wear. Therefore, the piston pin is assembled with a full floating fit in the connecting rod and piston bushings,
with relatively large clearances. Worn piston pin clearances up to..010" are satisfactory..
If it is necessary to replace the connecting rod bushings, remove them as follows:.