The Tony Quinn-owned McLaren 650S is set to resume its preparation for the Liqui-Moly Bathurst 12 Hour after an engine problem saw it retire from Practice 3 the Liqui-Moly Bathurst 12 Hour.

Klark Quinn returned the #37 Keltic Racing Darrell Lea McLaren he is sharing with his father Tony Quinn, Grant Denyer and Andrew Waite to the pits with a little over 35 minutes remaining in the 60-minute session.

With smoke pouring from the machine, the 650S took no further part in the session.

The McLaren had to sit out Practice 4 after a stray bolt was found to have caused damage.

Denyer has confirmed that the team has repaired the 3.8L twin-turbo V8 and will be back on track ahead of further practice and qualifying for the Mount Panorama classic on Saturday.

“It was a weird one,” said Denyer.

“We had an external bolt in the engine that’s not supposed to be there, and it spat out and punched a hole through the rocker cover – it must have been left in there after the last engine rebuild.

It was originally feared that the team would be forced to replace the engine.

“(It will be the) same engine. There was no damage aside from that so we’ve fixed the rocker and we’ll be back out again tomorrow,” Denyer said.

“We should be on-song. The setup’s been well-refined over the last couple of 12 Hours, but it is a shame that we couldn’t work up to it today.”
The Class A Am entry had recorded a best time of 2:07.01 during Practice 3.

On-track action continues tomorrow from 0800 AEDT with Practice 5, held over one hour.