Connecting Rod: Application and ID

Reference Number Or Bar Number:

Each rod falls into one of four tolerance ranges (from 0 to +0.024 mm, in 0.006 mm increments) depending on the size of its big end bore. It's then stamped with a number or bars indicating the range.
You may find any combination of 1, 2, 3, 4, or I, II, III, IIII in any engine.

Normal Bore Size: 51 mm (2.0 in)

NOTE:
- Reference numbers or bars are for big end bore size and do not indicate the position of the rod in the engine.
- Inspect connecting rod for cracks and heat damage.