South Western Railway disruption after biofuel clogs engines

South Western Railway apologised for the fuel issue which it said was under investigation

A train operator has reduced services after diesel engines were clogged with biofuel.

South Western Railway (SWR) said a fault was discovered on Wednesday in much of its diesel fleet at depots in Exeter and Salisbury.

It said the issue would disrupt services in the Romsey area and west of Salisbury until further notice.

BBC South transport correspondent Paul Clifton said SWR would run a fraction of normal services on the routes.

He said the issue would affect the West of England line for the next week.

SWR will run one train every two hours on routes connecting Salisbury to Exeter and Southampton.

One train an hour will operate between Salisbury and Basingstoke, while services to Westbury and Yeovil Pen Mill will not run.

The rail firm has apologised for the incident, which it said was under investigation.

Analysis

Paul Clifton, BBC South transport correspondent

The diesel engines on the trains at Salisbury depot use a small proportion of biofuel, much as cars and lorries do.

I'm told this biofuel has created a sludge in the engines and blocked fuel filters.

This is preventing the trains from running smoothly.

The fuel tanks will have to be flushed clean and the filters replaced. This is not a small task.

Salisbury depot has frequently won awards for the best and most reliable diesel train fleet in the country.

Not this year, it won't.