Fuel leaks onto the ground with a full tank on a slope
A factory safety recall, and one of the few faults on this truck that can start a fire without any warning light. The campaign describes it exactly: with the tank full and the vehicle parked facing forward on an upward slope, the fuel tank leveling valve may stop sealing if the fuel expands as the ambient temperature rises, and fuel can then leak onto the ground. The manufacturer's stated consequence is fire in the presence of an ignition source, and the remedy was to replace the valve. The pattern is what identifies it: no leak on level ground, no leak with half a tank, a puddle and a smell after the truck has sat nose-up in the sun on a full one. It is worth knowing that owners also report fuel leaking at the rear wheel well without that pattern, and one reports a leak that came back after the campaign repair — so a smell of fuel that does not fit the slope-and-full-tank picture still needs finding. Costa Rican driveways and parking spots are rarely level, which makes this a more likely find here than the campaign's home market would suggest.
Gen 32002–2004USSafety-criticalTechnical service bulletin (TSB)
Do not driveNo lo maneje
filteredDoes not fit the vehicle you selected
Provisional matchThis is safety-critical, and the match to your truck is only provisional: it was made on generation, market, year and engine alone. Narrow your selection, and confirm against your own vehicle, before acting on anything here.
Safety notice — Fuel system.
This affects a safety-critical system. Reference material only: for safety-critical work, consult a qualified mechanic.
Esto afecta un sistema crítico para la seguridad. Material de referencia únicamente: en trabajos críticos para la seguridad, consulte a un mecánico calificado.
Symptoms
- A strong petrol smell after the truck has been parked nose-up
- A wet patch or a puddle under the rear of the vehicle
- It happens with a full tank and never with a half-empty one
Likely causes
- The fuel tank leveling valve is no longer sealing as the fuel expands
- Another leak path in the tank plumbing — the filler neck, the rubber filler hose, or a fitting at the rear wheel well
Diagnostic steps
- Fill the tank, park facing up a slope in the sun, and come back to look underneathPoints toThe fuel tank leveling valve is no longer sealing as the fuel expands
- Repeat the same parking spot with the tank about half fullPoints toThe fuel tank leveling valve is no longer sealing as the fuel expandsRules outAnother leak path in the tank plumbing — the filler neck, the rubber filler hose, or a fitting at the rear wheel well
- Look up at the filler neck and the rubber hose behind the rear wheel for staining or crackingPoints toAnother leak path in the tank plumbing — the filler neck, the rubber filler hose, or a fitting at the rear wheel well
Fix paths
Have the campaign remedy done
$Difficulty 1/5
Where the campaign applies, a dealer replaces the valve. Ask before you pay for anything else — this is the manufacturer's own fix for the manufacturer's own defect.
Replace the tank valve
$$Difficulty 3/5
The part is still supplied for this generation outside the campaign. Fuel work belongs to somebody with the right extinguisher within reach.
Partsgen3-fuel-tank-safety-valve
Replace the filler hose
$$Difficulty 3/5
The other place a full tank weeps from, and a cheaper find. Worth checking first because it is visible from underneath without dropping anything.
Partsgen3-fuel-filler-hose
Sources
- NHTSA recalls database — Mitsubishi Montero, 2002 model year: campaign 04V319000, fuel tank leveling valve (Mitsubishi recall SR-04-008)archived copy
- NHTSA recalls database — Mitsubishi Montero, 2004 model year: the same campaign 04V319000, confirming the campaign's later covered model yearsarchived copy
- Luso Overland — MONTERO Gen3 Fuel Tank Safety Valvearchived copy
- NHTSA owner-complaint database — Mitsubishi Montero, 2002 model year; VIN-confirmed full-size Montero filings (ODI 769049, 10105501: fuel leaking at the rear wheel well on three separate occasions, and a leak that returned after the campaign repair)archived copy