Two-month-old vehicle suddenly catches fire on a motor way, our expert analysis determined the true cause of the fire and saved our client almost £80k

  • Despite the severity of the damage and initial reports, we were able to determine the true cause of the fire

  • Our insurer client received nearly 80k for the inspection and the entirety of the vehicle’s value



A vehicle that had only been leased for two months, with a recorded mileage of c. 1,000 miles; was being driven on the M18, when the dashboard displayed a warning stating that the engine was overheating and to pull over.

The driver pulled onto the hard shoulder; when he saw smoke from the engine, whilst still on the phone to the emergency services, the engine was engulfed in flames.

Once the police and fire services extinguished the fire, they checked the vehicle’s batteries, but were unable to determine the cause of the engine fire. It was also reported that there had been no unusual smells, problems, faults, or damage before the fire.

The model was not part of any recall by its manufacturer due to any known potential issue and had not required servicing or repair due to it being newly manufactured.

Our insurer client instructed one of our Forensic Engineers to determine how an engine fire could have occurred in a ‘brand new’ vehicle.

How we helped


Our Forensic Engineer examined the vehicle with a representative from the vehicle’s manufacturer, and a leasing agreement was recorded against the vehicle, and no visible extras or modifications were fitted.

The (few) un-burnt areas of the vehicle were in a generally good condition, and there were no signs of pre-fire collision damage or body repairs.

The fire damage had disabled the car’s engine, transmission, brakes, steering, and electrical systems and burnt out the car’s front end, which had been consumed by the fire, and the laminated windscreen was almost completely burnt out.

Despite initial reports, there was no evidence that the voltage converter in this vehicle caused the fire, as a short circuit in the converter would not have caused the vehicle’s engine to overheat prior to the fire and the damage was also remote from both battery packs.

The vehicle’s high voltage system’s drive motor, wiring, inverter, spark plugs, engine coil packs, and low voltage electrical components all displayed no signs of unusual pre-fire activity.

Once the vehicle’s alternator was examined, severe damage was established, but there were still no signs of it being the cause of the fire. The alternator is driven via a drivebelt and pulley system that incorporates an adjustable drive belt tensioner. Its pulleys displayed the charred remains of its belt.

The engine’s water / coolant pump is also driven via a separate drivebelt and pulley system. However, unlike the alternator, there were no traces of its drivebelt on the water pump’s pulley or the corresponding pulley.

A search of the fire debris revealed no trace of the water pump’s drive belt, and the lack of any remains indicated that the water pump’s drivebelt separated and / or became detached pre-fire causing the engine’s coolant circulation to fail and then overheat (as reported) due to the consequential rapid rise in temperature. It is likely that a system rupture subsequently ejected coolant onto the hot engine components where it ignited.

This was a unique case, as the water pump drive belt would not normally have required attention in the short period between the vehicle’s manufacture and the fire.



Due to the vehicle being two months old, with recorded mileage of c. 1,000 miles, no external influence being determined, and the vehicle’s standard warranty, it was declared that a claim from the manufacturer for the insurer’s reasonable outlay would be the correct decision.

The Forensic Engineer’s extensive report, enabled the vehicle’s insurer to make a full recovery of its outlay from the vehicle’s manufacturer (c.£77,980)

Find out more about our forensic engineering and investigation services here:

    Keep up to date with Davies