Caterpillar 3406E — Crankshaft Main Bearings - Install
Repair & overhaul · Bottom end
For the Caterpillar 3406E, from the Caterpillar service manual.
Applies to: Caterpillar 3406E, Caterpillar 3406E / 3456 engine
Before you start
- If crankshaft turned wrong direction, bearing tab can damage cylinder block/crankshaft
Procedure
- Install new upper main bearings using bearing tool in crankshaft oil hole, turning crankshaft to seat bearing (non-tab end first)
- Install new crankshaft main bearings in main bearing caps
- Check crankshaft main bearing clearances (0.091-0.186 mm new; max 0.25 mm used)
- Apply clean engine oil on bolts; install thrust plates at No. 4 main bearing with 'Block Side' toward block
- Install main bearing caps and bolts, ensure cap numbers match block and arrows face front
- Tighten bolt on bearing tab side to 260 + 14 N-m (190 + 10 lb ft), then opposite side to same torque
- Mark bolts and caps; tighten opposite side an additional 120 + 5 degrees (2 flats), then tab side same
- Check crankshaft end play with dial indicator (0.15-0.55 mm new thrust plates; max 0.89 mm used)
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Main bearing clearance new 0.091-0 FridayParts $31.69.186 mm, max used 0.25 mm; bolt torque 260+14 N-m plus 120+/-5 degrees x2; end play 0.15-0.55mm new, max 0.89mm used
Full service-parts list: Caterpillar 3406E →, Caterpillar 3406E / 3456 engine →
Source: Caterpillar 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.