F1 | Sauber: still problems in the pits, the light nut needs to be revised

Even in Australia, Sauber was a negative protagonist in the pit stop phase. After the problems already experienced in Bahrain and Saudi Arabia, with two long stops that had negatively affected the race of both drivers, there was no shortage of confusing situations in Melbourne too, which also led to the team receiving a fine.

After what happened in the first two races, the team made some temporary changes in order to try to keep the situation under control while waiting for a definitive solution that will only arrive later in the season. The hope was that, despite making slower and more conservative stops, the problems in Sakhir and Jeddah could be avoided, which cost numerous seconds and ruined the chances of being able to fight for a good placing.

However, there was no shortage of difficulties in Australia too and Bottas lost 28 seconds, effectively being excluded from the fight for points, despite having also had a good qualifying. Compared to the other two events, however, in Melbourne the fastening nut came out of the gun and rolled into the pit lane, exactly where the other cars pass. In fact, this happened twice, but on the first occasion one of the mechanics managed to catch it before it ended up in the fast lane.

However, the episode in which the dice ended up in the fast lane prompted the race management to report what happened to the FIA ​​stewards for safety reasons. After investigating the matter, the stewards determined that “the team lost control of a wheel nut during a pit stop, causing a potentially dangerous condition in the pit lane during the race”, imposing a fine.

Xevi Pujolar denied that the loss of the nut was the result of changes made by the team after Jeddah: “It shouldn't have happened, but it's not due to the changes we made. From what we saw in free practice and pit stops we were reasonably confident that everything would go well in the race.”

According to what Pujolar explained, the major problems occurred in racing situations, while they would not have been encountered during tests, free practice and winter practices, which is why they were not noticed before the Grands Prix. Realistically it could be the fact that in racing conditions the temperatures also rise, transmitting part of the heat generated by the tires and brakes to the parts, an aspect to be replicated during the static tests in the factory or in free practice.

The cause would be linked to the revision of the design with lighter materials which, however, did not give the desired results in terms of robustness. In fact, to speed up operations and improve the performance of the cars, the team has made important investments, in order to reduce pit stop times, which in recent years have been among the slowest on the grid. The problem is that the material does not provide the expected strength values, particularly when temperatures rise: what is clear is that, in some way, a deformation of the thread occurs, making it more difficult to remove the nut.

Kick Sauber mechanics make a pit stop on Zhou Guanyu's car, Kick Sauber C44.

Photo by: Andrew Ferraro / Motorsport Images

“From the first race we encountered some problems with the pit stops, seeing stripped nuts. It's something we don't encounter when we do free practice, or even during the winter, we haven't encountered any problems. But every time we find ourselves in a race situation, the problem becomes more critical. In Australia we made some small changes to try to contain the problem. It's not robust enough and we had a problem in the pits.”

“As long as we have this problem, it will be very difficult for us. It is not a problem related to the mechanics, who are doing everything correctly. We have a hardware problem and we just need to make sure we have time to find the solution and spare parts. We will try to solve the problem for Suzuka, but a definitive solution will take more time.”

Pujolar confirmed that the parts to be modified come from an external supplier and, more generally, given the design and manufacturing process, including stocks, it will still take some time before we see a solution that can put an end to the problems. Furthermore, the Sauber engineer explained that it is impossible to go back to the parts used last season, as the change in layout made to the front of the single-seater for this championship has made the various elements incompatible with each other.