John Deere — Replacing Fuel Filter and Dosing Elements (4045)
Maintenance · Fuel filters and dosing element
From a John Deere service manual — check it applies to your exact model before use.
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Before you start
- Before maintenance, place machine in Key OFF and disconnect electric fuel transfer (lift) pump or battery.
- Escaping fluid under pressure can penetrate the skin causing serious injury; relieve pressure before disconnecting fuel lines.
Procedure
- Close fuel shut-off valve, if equipped; clean assemblies and surrounding areas.
- Disconnect water in fuel sensor wiring from primary fuel filter.
- Loosen drain plugs and drain fuel into a suitable container.
- Rotate retaining rings clockwise 1/4 turn; remove with final and primary filter elements.
- Loosen ring and remove water separator bowl with primary element; drain/clean/dry bowl.
- Inspect filter mounting base for cleanliness; clean as required.
- Install new filter elements onto mounting bases; index and seat firmly.
- Align element keys with slots in filter base.
- Install retaining ring, hand tighten counterclockwise until it snaps into detent.
- Install water separator bowl on primary fuel filter and tighten ring.
- Turn dosing element with a filter or strap wrench to remove; discard.
- Remove cap from new dosing element canister; wipe header sealing surfaces.
- Install dosing element by hand firmly against header; apply extra 3/4 turn after gasket contact.
- Reconnect water in fuel sensor wiring; open fuel shut-off valve.
- Key on 30 seconds to prime, then start engine and check for leaks.
Source: John Deere 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.