Caterpillar C-3406B / C-346 — Slave Piston Adjustment Procedure
Adjustments
For the Caterpillar C-3406B / C-346, from the Caterpillar service manual.
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Before you start
- Pay special attention to this adjustment to ensure maximum brake operating efficiency and prevent engine damage. Overtorquing the locknut could damage the slave piston adjusting screw.
Procedure
- Make the adjustment with the engine stopped and cold (stabilized water temperature of 140 °F (60 °C) or below); exhaust valves on the cylinder must be closed.
- Loosen and back off the adjusting screw locknut and back out the slave piston adjusting screw until the slave piston is seated in its bore.
- Turn the adjusting screw in until a slight drag is felt on the feeler gauge between the slave piston feet and the bridge.
- Torque the lock nut to 16 lbft (22 N·m).
- Remove the timing bolt, rotate the engine over to cylinder 6 TDC, reinstall the timing bolt and continue the valve and slave piston adjustment.
- After the locknut is torqued, recheck clearance with the Jacobs feeler gauge.
Tools required
- Jacobs feeler gage P/N 013184 (0.070 in) for C-346B on 3406B engine Amazon
- Jacobs feeler gage P/N 007446 (0.060 in) for C-346, C-346A and C-346B on 3406 engine
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Slave piston lash C-346B on 3406B FridayParts $16.28 SinoCMP $69.00 KuduParts $675.00 0.070 in (1.78 mm)
- Slave piston lash C-346/C-346A/C-346B on 3406 0.060 in (1.52 mm)
- Lock nut 16 lbft (22 N·m)
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.