Perkins — Connecting rod bearing clearance - to check
Maintenance
From a Perkins service manual covering: 403C-11, 403C-15, 404C-22. Check it applies to your exact model before use.
Applies to: Perkins 403C-11, Perkins 403C-15, Perkins 404C-22
Procedure
- Clean the bearing surfaces and the exposed half of the crankshaft journal.
- Fit the bearing caps and tighten the bearing cap to torque.
- Remove the bearing cap of the clearance to be checked.
- Place a piece of Plastigauge across the full width of the bearing surface on the crankshaft journal, fit the bearing cap and tighten the bearing cap setscrew to the specified torque.
- Remove the bearing cap but do not move the Plastigauge.
- Use the Plastigauge envelope to measure the widest point of the Plastigauge; this reading indicates the bearing clearance.
- If the bearing clearance is not within the specifications the crankshaft must be reground and undersize bearings fitted.
Tools required
- Plastigauge Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 403C-11 eBay $31.20 FridayParts $10.50 SinoCMP $51.00 journals 1 and 2: 0.039 - 0.092 mm standard; journal 3: 0.029 - 0.082 mm standard; service limit 0.20 mm
Full service-parts list: Perkins 403C-11 →, Perkins 403C-15 →, Perkins 404C-22 →
Source: Perkins service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.