McLaren grapples with Honda oil system problem

McLaren's running on the opening day of testing was hit by an oil system problem that stopped the car after just one lap.

With Fernando Alonso behind the wheel of the MCL32 (pictured above adorned with telemetry equipment) on the first day at the Circuit de Barcelona-Catalunya, the Spaniard completed an installation lap before returning to the garage for checks. Honda discovered a problem with the oil system at that point, requiring the rear of the car to be opened up in order to address the issue.

"We have an oil systems issue which requires a full investigation," a Honda spokesperson said at the time. "We plan to run again today, but due to the difficult access location it will take several hours to resolve."

After starting to investigate, Honda opted to replace the whole power unit in order to get back on track as soon as possible. The Japanese manufacturer estimated the issue would take four or five hours to fix, with Alonso returning to the track with two hours of the session remaining. On his second lap, Alonso returned to the pit lane with the engine switched off but was able to continue running soon after. Up to speed, the Spaniard showed some promising pace, setting a 1m25.586s – ninth fastest at that point.

RACER understands the problem does not relate to Honda's new oil supplier – Castrol – following its switch from ExxonMobil products this winter.

While the problem occurred on the opening lap of the test, McLaren completed nearly 100km of running during a filming day on Sunday.