A freak problem closed Longbird Bridge to marine traffic once again yesterday - just days after engineers announced they had found a solution to a separate long-standing fault.

Engineers are hoping to find a replacement for a valve which blew open yesterday morning, but may not be able to find one until Monday, meaning larger boats will need to find a detour.

On Wednesday, Works and Engineering minister Alex Scott revealed that engineers flown in from the United States had solved the problem of the bridge's wedges deflecting in the summer heat, causing the bridge to break down.

And he announced the bridge would then be open to mariners hoping to sail under the structure during the Cup Match holiday.

But on Friday morning, the bridge was again off limits to larger boats after the valve blew.

Mr. Scott said yesterday: "This had no relation to the deflection experienced when the heat caused the wedge to jam.

"Any engine at any given time could blow a ring and that's what happened this time. It's just one of those unforeseen things that can happen to an engine.

"There was an excess of oil and if we had tried to continue, we could have caused the bridge to run into major problems.

"I apologise to marine traffic. We were hoping to give them access to Castle Harbour and the Sound during the holiday weekend, but this was not one of the problems we thought we might have had.''

Meanwhile, Mr. Scott warned reckless motorists they could cause a serious accident if they jump red lights at the bridge. He said there were two serious incidents in the past few days.

He said the bridge operator will report anyone seen jumping the red light to the Police.

"We've twice come close to a serious accident when people have ignored the red light and tried to beat it,'' he said.

"People could find themselves half on and half off the bridge as it begins to move with disastrous consequences.

"The bridge operator will take the number of anyone that goes through the red light and will report it to the authorities, not to be punitive, but in people's own best interests.''