For a brief period at the height of the industrial conflicts of the 1970s between the trade unions and both Labour and Conservative governments, few union leaders were better known than Derek Robinson, who has died aged 90. As the convener of one of the largest manufacturing complexes in the country, the British Leyland motor company’s Longbridge plant on the edge of Birmingham, and an unabashed member of the Communist party, he was known as Red Robbo. This catchy nickname, a headline writer’s dream, allowed him to be portrayed as a symbol of the conflicts that were bringing the industry to its knees. Management blamed him for the 523 disputes at the plant in 1978-79.

His contested dismissal by the new broom at BL, Sir Michael Edwardes, in 1979 brought workers briefly out on strike. It marked a declaration of intent, a change from the postwar pattern of monolithic union organisations in large plants, mirroring an introspective management, to more assertive international management. A few years later Robinson’s own union was discussing no-strike deals to encourage Japanese companies to establish themselves in the UK.

Born in Cradley Heath, Staffordshire, Robinson came from a family that had worked in the chainmaking industry, and through encouragement from his mother became an avid reader. At 14 he began his engineering apprenticeship at Longbridge (which he continued to call “the Austin” after its old company name) and qualified as a toolmaker. Two brothers also worked there. He became a shop steward and joined the Communist party of Great Britain in 1951, during the Korean war, remaining a member until being expelled in the 1990s.

Derek Robinson attending the ‘March to Save Rover’ in Birmingham in 2000. Photograph: David Jones/PA

He was a protege of the long-serving convener Dick Etheridge, another communist, whose championship of his members’ interests did not prevent the then BL chairman, Lord (Donald) Stokes, giving a party for him when he retired in 1975. Robinson succeeded Etheridge at the moment when BL was running out of money. Stokes was dispatched and the unions were drawn into the discussions for the Ryder report, which brought the huge investment that they had sought and promises of the participation that had been a key goal of the stewards.

Robinson followed the party line, favouring nationalisation of the industry, and he cooperated with management in its replacement of the old piecework system, widespread in the Midlands. This paid workers by the amount they produced, but a maze of different rates meant that every time a new component or model was introduced rates had to be renegotiated, and industrial disputes and strikes followed. It occupied hours of management and union time and individual plants could have two or three stoppages a day as a result.

Robinson’s support for change brought criticism from the Trotskyists who were active in Leyland plants for limiting the chances of union intervention. But he declared his commitment to the company’s success: “If we make Leyland successful, it will be a political victory. It will prove that ordinary working people have got the intelligence and determination to run industry.”

However, on the national stage he opposed the social contract agreed between the TUC and the Labour government, which attempted to restrain runaway inflation by agreeing wage restrictions in exchange for new employment legislation. He told a communist meeting in London that he was quite prepared “to lead a mighty orchestration of workers” to smash it.

Leyland’s troubles worsened. Skilled workers, members of Robinson’s own union, the Amalgamated Engineering Union (now part of Unite), embarked on a lengthy strike. He opposed it, fruitlessly, and it starved the company of resources. In 1977 Robinson’s nemesis, the Anglo-South African businessman Edwardes, arrived.

His initial reorganisation, which included the loss of 15,000 jobs and the closure of a Liverpool plant, was accepted by the unions when he announced it to 700 union representatives and forced a vote. However, as it expanded, and Edwardes started to consult the workforce directly, going over union leaders’ heads, Robinson and his colleagues resisted. In 1979, a recovery plan involving the closure of 13 factories in exchange for £500m more government funding was accepted by a huge majority in a company ballot, but a pamphlet produced by the conveners against the plan was used as a way of removing Robinson.

Edwardes, who it later transpired had a transcript of the meeting at which the pamphlet scheme was discussed, had Robinson fired. When a strike ensued, Edwardes held a tense meeting with Robinson’s national union executive, which was dominated by Labour rightwing Midlanders politically hostile to him, and they agreed to an inquiry. Robinson continued to be paid, but the inquiry found against him and took so long that time ran out for an industrial tribunal settlement. When a Longbridge meeting voted 10 to one against another strike in support, Robinson admitted defeat.

Edwardes explained it as an essential move to get Leyland’s new popular car into production. “We did it exactly a year before the Metro was launched because the car’s management told me that they could not meet productivity requirements that would get the Metro down to budget unless they could manage Longbridge, and they could not do that with Robinson running his own private disruption.”

Robinson, who described Edwardes as “ruthless and cynical”, said: “I did a better than average job in the interests of BL workers. When the critics say we were just a bunch of militants, they forget we were actually fighting for jobs. We didn’t come out on strike just for the sheer fun of it.”

In subsequent years, he had numerous applications for engineering jobs rejected and failed in an attempt to become a Midlands organiser for the union. He continued his party activities, becoming a sales representative for its Morning Star newspaper, stood unsuccessfully four times for the parliamentary constituency of Birmingham Northfield and lectured on industrial relations at Bilston Community College.

He married three times.

• Derek Robinson, trade unionist, born 1927; died 31 October 2017