Caterpillar 3406 — Fuel Filter Replacement and Priming
Maintenance · Fuel System
For the Caterpillar 3406, from the Caterpillar owner's manual.
Applies to: Caterpillar 3406
Before you start
- Do not fill fuel filters with fuel before installing - causes unfiltered/contaminated fuel
Parts for this job
- 3S3875 Fuel filter eBay $49.99
Part numbers from the service-parts list for Caterpillar 3406. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Stop the engine
- Shut off fuel tank supply valve to filters
- Turn ignition/start switch OFF or disconnect batteries
- Loosen bolt on primary filter housing and remove filter case
- Wash reusable primary element in clean nonflammable solvent
- Tighten primary filter housing bolt to 24+/-4 N-m (18+/-3 lb ft)
- Clean gasket sealing surface of final filter base and apply clean diesel fuel to new gasket
- Install new final filters, tighten until gasket contacts base then 3/4 turn more by hand
- Open vent valve and operate priming pump until fuel flows free of air bubbles
- Close vent valve, lock priming pump, and crank engine to start
Specs & values
- Fuel line nuts 40+/-7 N-m (30+/-5 lb ft)
Full service-parts list: Caterpillar 3406 →
Source: Caterpillar owner's 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.