- Excessive clearance on the sides of connecting rods can sometimes cause a ticking sound that resembles a valve train noise, but comes from the crankcase.
- The noise can go away during a power balance test.
- Spark knock can intensify the noise caused by excessive rod side clearance.
- Closely examine all piston skirts and bearings for unusual wear patterns that may indicate a twisted rod.
- Rods suspected of being bent or distorted can be checked with a rod alignment checker. Normally a damaged rod is replaced, although equipment is available to straighten them and to rebore the small and big ends.
If the connecting rod fails inspection, it is not always necessary to replace it. a connecting rod can be reconditioned.