George Russell's Hungarian GP Power Unit Change: Water Leak, No Penalty, and a Season of Reliability Woes

Precautions Mercedes took

• Immediate on-track instruction: Rather than risk catastrophic engine failure, Mercedes told Russell to park the car at Turn 1 after his last lap instead of driving it back to the pits .
• Full power-unit change: The team opted to fit a completely fresh V6 engine (ICE) for race day rather than attempting a repair .
• Move to 4th unit of the season: This power unit became Russell's fourth of the 2026 season, which is still within the regulated allocation, so no further restrictions apply .

Grid position and penalty status

• Grid position: Russell originally qualified 7th. However, teammate Kimi Antonelli received a 3-place grid penalty for impeding, which promoted Russell to 6th on the grid .
• Penalty status: The power-unit change did not incur a grid penalty. Because Russell was moving to only his fourth ICE of the season — within the allowed limit under F1's 2026 PU regulations — the change was permitted without a drop .

The water leak in the broader reliability context

This water leak is the latest in a string of power-unit problems that have plagued Russell's 2026 season.

• Silverstone (British GP): Russell retired from the lead fight on Lap 34 due to a water leak, though Mercedes confirmed the engine was salvageable and could be reused later .
• Spa-Francorchamps (Belgian GP): Russell suffered a mysterious deployment/power glitch that contributed to him qualifying half a second behind Antonelli, and was then taken out on Lap 1 of the race. Mercedes initially blamed the glitch on Russell's driving style before later identifying it as a software control issue in the power unit .
• Hungaroring: Despite Mercedes publicly expressing confidence that the software glitch was resolved ahead of Hungary , a new physical water-leak problem emerged in qualifying — this time causing internal damage to the ICE and requiring an overnight swap .

In total, Russell has now had three distinct power-unit incidents across three consecutive race weekends (Silverstone, Spa, Budapest), spanning two different failure modes (software deployment glitch and physical water/coolant leaks). While Mercedes believes the software issue is now fixed, the recurrence of a water leak — after a similar issue ended his British GP — points to an unresolved mechanical vulnerability in his PU allocation .