Explain what you know and what you only suspect. A warning light or rough running after a refill can be important, but it is not a laboratory identification of the fuel. The source, timing, vehicle history and any other affected equipment help establish the next step.
Different contaminants need different responses
Petrol mixed with diesel, AdBlue in a fuel tank and water in fuel are distinct problems. An unknown liquid or debris also needs to be described rather than automatically treated as one of those incidents. Product containers, receipts and maintenance information can help clarify the situation.
A drain may be part of the response, but it is not a universal repair. Cleaning, filters, tank condition and further checks may need attention. If the cause is a damaged filler, suspect storage source or another ongoing issue, removing one tankful will not establish that the source problem has been resolved.
Symptoms and the refuelling history
Record when the vehicle was filled, where the fuel came from and when any loss of power, poor running, warning or non-start began. Explain whether symptoms appeared immediately or after a period of use or storage.
Do not repeatedly run the engine to reproduce a suspected fuel fault. Where contamination is known or strongly suspected after an incident, stop safely and seek assessment. If the symptoms could have another cause, tell us rather than assuming a fuel drain is automatically the correct service.
Shared supplies, bowsers and stored fuel
A vehicle filled from a forecourt and equipment supplied by a depot tank have different supply histories. Tell us if the fuel came from a drum, bowser or storage tank, how long it may have been stored and whether more than one vehicle or machine used it.
If a shared supply is suspect, prevent additional use where safe while an appropriate assessment is arranged. Large-volume storage work, fuel testing and tank cleaning should not be assumed to be included in a standard mobile vehicle drain. Their requirements and scope need to be agreed separately.
What to expect from an enquiry
Provide the vehicle or machine identification, location, estimated fuel quantity, suspected contaminant and operating history. For a commercial site, include the responsible contact, access rules and person authorised to approve work.
The proposed work depends on the evidence and access available. The technician will explain the appropriate service, cost and any recommendation for further diagnosis. Disposal arrangements form part of handling removed contaminated fuel; do not transfer it to drains, soil or another vehicle.
Attendance, access and the cost of the work
Contamination enquiries are assessed for the vehicle, fluid, quantity, access and whether the engine has run. AdBlue, water and unknown-fluid work should not be assumed to have the same scope or price as a simple petrol-and-diesel mix.
We cover mainland Scotland and the islands. Arrival estimates are confirmed for the vehicle’s actual location and current availability. Time on site is a separate matter and depends on the work. Neither a coverage page nor an initial enquiry is a promise of a fixed completion time.
Before attendance, identify the person authorised to approve the work. The technician explains the proposed service and confirms the cost before starting. If you intend to use a policy, lease agreement or hire-company process, check its requirements with the provider.
Find your coverage areaFuel contamination: common questions
Does rough running prove the fuel is contaminated?
No. Similar symptoms can result from other faults. The timing and fuel history are useful information, but the vehicle still needs an appropriate assessment.
Can you identify an unknown liquid by its colour?
Colour or smell alone should not be relied on. Keep any container or receipt and explain the circumstances; further identification or testing may be needed.
Can you clean a bulk storage tank?
Discuss that as a separate enquiry. Storage capacity, fuel type, access and the required service are different from a routine vehicle fuel drain.
What if more than one machine is affected?
Record the assets, source used and operating history, and stop further use of a suspect supply where safe. A shared-source issue needs a broader scope of assessment.