(Bloomberg) -- Boeing Co. factory workers rejected a new labor contract that would have increased their wages by 35% over four years, dealing a blow to the embattled aircraft manufacturer as it tries to overcome a crippling work stoppage.

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Some 64% of the union members who cast ballots on Wednesday voted against the tentative agreement, according to the International Association of Machinists and Aerospace Workers district representing the 33,000 striking workers.

“We remain on strike,” IAM District 751 President Jon Holden said after the vote count. “Our members deserve more and have spoken loudly.”

While the opposition this time was smaller than the overwhelming 94% vote to reject the company’s initial offer in September, the result is a setback to Boeing’s efforts to get operations back on track. The planemaker has been forced to suspend work on its 737 and larger 767 and 777 airliner models at its Seattle-area manufacturing hub for more than a month, weighing on its finances and putting credit-rating companies on alert for a possible downgrade to junk status.

The move will send Boeing and the union back to the negotiating table following six weeks of stop-start talks that eventually led to the White House dispatching Acting Secretary of Labor Julie Su to Seattle to help break the stalemate. While Boeing’s latest pay offer was a bump from its initial 25% increase, workers are still angered by the failure to reinstate their defined-benefit pension plan.

“The loss of the pension is still right at the heart of this for many” union members, Holden said. “We’re going to put all cards on the table” to see what Boeing can offer in lieu of the pension plan, he added.

The strike has derailed the planemaker’s financial recovery, and its after-effects will linger deep into 2025. Boeing expects to burn cash next year, one reason the company is preparing a potential equity sale to bolster its reserves, executives said during an earnings call Wednesday.

The manufacturer was on track to generate a surge of revenue from rising jet deliveries prior to the labor strife. With that activity all but halted, Boeing expects to burn around $4 billion in cash during the fourth quarter, similar to its outflow earlier this year, according to Chief Financial Officer Brian West. The would bring the company’s total free cash outflow to around $14 billion for 2024, its worst performance since the Covid pandemic flattened air travel in 2020.