Cummins/Onan — Draining Water and Sediment from the Fuel Filter
Maintenance
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan MDKB, Cummins/Onan MDKBH
Before you start
- Diesel fuel is combustible and can cause severe personal injury or death.
Parts for this job
- 1522143081 Fuel filter — Cummins/Onan MDKB Amazon eBay $37.58 KuduParts $13.00 FridayParts $15.69
- 149-2106 Fuel filter — Cummins/Onan MDKBH Amazon eBay $34.99 NAPA $61.61 KuduParts $68.00
Part numbers from the service-parts lists for Cummins/Onan MDKB, Cummins/Onan MDKBH. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Disconnect the negative (-) battery cable and close any fuel supply and return valves.
- Open the front access door and drain the filter (about 1/2 cup [120 ml]) into a suitable container by removing the drain plug.
- Re-install the drain plug and dispose of the drain-off per local regulations.
Specs & values
- Drain about 1/2 cup (120 ml)
Full service-parts list: Cummins/Onan MDKB →, Cummins/Onan MDKBH →
Source: Cummins/Onan operator'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.