To identify an older Moeller portable fuel tank, compare the capacity on the label, the shape and the manufacturer's part number. The Ultra3, 6BOW and Ultra6 have different sizes and intended arrangements. A replacement vent cap must match the tank's original fill neck.
Moeller portable tank identification chart
| Part number | Part | Capacity | Unpacked size / check |
|---|---|---|---|
| 620003LP | Ultra3 portable tank | 3 US gal | 17 × 9 × 9¾ in |
| 620040LP | 6BOW portable tank | 6 US gal | 19 × 16½ × 11 in |
| 620049LP | Ultra6 portable tank | 6.5 US gal | 21¼ × 13½ × 10 in |
| 305994-10 | Two-stage replacement vent cap | Replacement cap | Check tank fill neck |
Tank sizes are exterior unpacked dimensions. Allow room for hoses and safe access. The replacement cap is not a tank and its compatibility is determined by the original fill neck.
How to identify a replacement tank or cap
- Read the manufacturer's number on the tank or original cap, if still visible.
- Measure its exterior length, width and height. The three-gallon Ultra3 is compact, the six-gallon 6BOW is broad, and the Ultra6 is longer.
- Inspect the fuel-withdrawal connection, original hose and securing arrangement before buying a tank.
- If replacing the 305994-10 cap, match the exact fill-neck profile. The two-stage vent and pressure-relief design is not a universal substitute.
- Use the proper marine fuel-system and storage instructions and inspect the old tank for damage or leaks.
Do not infer tank compatibility from its red colour or the cap's similar appearance. The original fittings, mounting space and fuel-system requirements must match.
Compare matching Moeller product photographs
Use the part numbers below to compare original equipment, then check the individual UsedRVParts listing for condition and availability.
Moeller 620003LP — Ultra3 portable tankCompact three-gallon tank with partitioned reserve area. Check the original tank, connections and exact part number.Check product details and availability
Moeller 620040LP — 6BOW portable tankBroad tank intended for a suitable inflatable or dinghy bow. Check the original tank, connections and exact part number.Check product details and availability
Moeller 620049LP — Ultra6 portable tankLonger tank with rotating fuel withdrawal assembly. Check the original tank, connections and exact part number.Check product details and availability
Moeller 305994-10 — Two-stage replacement vent capTethered cap with sealing click and pressure management features. Check the original tank, connections and exact part number.Check product details and availability
UsedRVParts viewing and pickup in Kelowna are by appointment.