In the immediate aftermath of the contest team boss Christian Horner said: “We will need to conduct a full investigation into what happened, but it looks suspiciously like the failures are related to each other and it may be an issue with the fuel system.”
That theory gained traction and by Monday F1 journalist Mark Hughes – who sits in the commentary box acting as a ‘spotter’ for Sky Sports F1 commentator Martin Brundle and David Croft – declared the suspected reason for the failures was ‘fuel cavitation’.
“Fuel cavitation tends to occur as the last dregs of fuel are being pumped around near-empty tanks,” he wrote in his the-race.com column.
“As can be imaged, the fuel is heavily sloshed around because of the loads being fed into the car and no matter how well-designed the tank’s baffling system, the temperature of the fuel increases when this occurs.”
“At a certain point of temperature the fuel begins vaporise and there will be a vapour lock in the pump, the fuel pressure dives and the pump is briefly pumping fresh air.
“The sudden load changes as the system pressurises and depressurises (together with the excess heat inside the pump from the vaporising fuel) will tend to damage the pumps and eventually they can no longer feed fuel to the engine.”
Red Bull have since stated they will have a fix in place in time for this weekend’s Saudi Arabian Grand Prix.
Theory versus Facts
It read like a good theory. But how would a fuel pump failure lead to Sergio Perez brakes locking up to the point that they span his car around and left it immobilized?
On Monday night Dutch publication De Telegraaf announced they had heard from FIA and Red Bull sources that indicated the fuel pump was not to blame for the demise of both Red Bulls. Indeed, as the fuel pump is a bulk standard piece of equipment not developed by teams but supplied as a customer component by the Italian company Magneti Marelli, it was strange no other teams reported problems.
Additionally, normally when fuel starvation is suspected, pit-walls advise their drivers to swerve and rock their cars in attempt to extract more fuel from the tanks or clear any blockage. This did not happen in Bahrain.
Whatever the reason for Verstappen’s and Perez’ cars to grind to a halt, their Milton Keynes Red Bull team has has just five days to identify and fix the problem.