Burnham-On-Sea - Two lanes of the southbound carriageway, near Sedgemoor Services, were closed while fire crews dealt with the incident, pictured here.
Eyewitness Lester Solway told Burnham-On-Sea.com, "The Alleys low loader lorry was carrying the Royal Scot 6100 steam locomotive from Crewe to the West Somerset Railway when a fire broke out at the rear of the low loader."
Two fire appliances from Weston-super-Mare and one from Burnham attended the blaze, along with the Highways Agency.
The hard shoulder remained closed until after 19:00 when an alternative lorry was brought to the scene.
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