Mercedes reveal "further investigation" needed on Valtteri Bottas' power unit

Russian Grand Prix

Mercedes reveal "further investigation" needed on Bottas power unit

Bottas was hit with a 15-place grid penalty for the Russian Grand Prix

Sam Hall

Tuesday 28 September 2021 05:00

Mercedes is to carry out "further investigation" on Valtteri Bottas' power unit after a problem materialised during the Russian Grand Prix weekend that resulted in the latest switch.

Bottas started towards the back of the grid for the second race in succession after taking a fifth power unit - internal combustion engine, turbocharger and MGU-H specifically - after receiving his fourth in Italy.

Initially, Mercedes declared the change was for "tactical" reasons after Bottas had qualified seventh at the Sochi Autodrom. Post-race, the Finn said the engine used in Monza was "gone".

Article continues under video

Shedding further light on the issue, Mercedes trackside engineering director Andrew Shovlin said: “We had another problem with that [power unit] during the weekend.

"That power unit, we need to do a further investigation on it and have a look at it back at Brixworth.

"But it was simply a case of looking at where he was qualifying, thinking that we might need to take another at some point. We just decided to go for that and put a new power unit in."

Mercedes did not expect overtaking issues

The change cost Bottas a 15-place penalty but with Antonio Giovinazzi taking a five-position hit for a gearbox switch and Max Verstappen, Charles Leclerc and Nicholas Latifi also taking back-of-the-grid PU penalties, Bottas only dropped nine positions.

Despite a fresh PU and the expected ease of overtaking, Bottas struggled. Before a late switch to intermediate tyres, he had only made up two places on his starting position of P14.

“When we made the decision, we thought it would be a race where we could recover more easily than we did," explained Shovlin.

“I think knowing how hard it was to overtake, we might have taken a different view on that.

"But it was really the case with the wet qualifying not having performed at the level of the car, we thought that would be the logical time to take it.”