(Updates with new request by Caixa)
By Carolina Mandl and Tatiana Bautzer
SAO PAULO, Oct 3 (Reuters) - Brazilian state bank Caixa Economica Federal has filed a legal motion requesting the liquidation of engineering conglomerate Odebrecht SA, according to court documents seen by Reuters, in what could be a dramatic end to the graft-plagued company.
Caixa also demanded that creditors appoint new management at the conglomerate and its subsidiaries if the judge does not order the company's liquidation.
The move by Caixa adds pressure on Odebrecht to restructure its debts in one of Latin America's largest-ever bankruptcy cases. The group filed for bankruptcy protection in June, with total debt of 98.5 billion reais.
One of Odebrecht's largest creditors, Caixa has been challenging the company's decision to include foreign bondholders for one of its units in the case.
Among the 21 Odebrecht affiliates that joined the bankruptcy proceeding was Odebrecht Finance, the issuer of $3 billion in bonds guaranteed by construction unit OEC.
Caixa said in the documents it sees this move as a strategy by Odebrecht to use the bondholders' votes to approve a restructuring plan over the objections of other creditors.
Odebrecht did not immediately comment on the latest complaint by Caixa.
In August, construction unit OEC reached an agreement with bondholders to restructure its debt at a 55% discount, cutting obligations from $3.2 billion to $1.4 billion.
In the court document filed on Thursday, Caixa also said that Odebrecht has not filed yet a proper restructuring plan as required.
Last month, Odebrecht filed an offer in court to swap creditors' debt for instruments similar to equity.
Other lenders have also said they do not agree with Odebrecht's restructuring plan. State-controlled bank Banco do Brasil SA requested the judge overseeing the bankruptcy protection annul the debt restructuring plan presented to the court last month.
In the request, Banco do Brasil complained about the lack of details such as which assets would be put up for sale and a time frame for recovery of the debt.
Banrisul, Votorantim SA and Banco Santander Brasil SA have objected to the plan and called for an immediate creditors meeting to discuss the issue.
Odebrecht did not immediately comment on Caixa's request for liquidation. In an earlier comment about the other banks' objections, Odebrecht said the requests were "a natural step in the restructuring" and "formalities."
$1= 4.0882 reais Reporting by Tatiana Bautzer; Editing by Chizu Nomiyama, Dan Grebler and Cynthia Osterman