The line operates two diesel shunters , one a Drewry shunter ( works number 2566 , current number D1995 ) , named `` Heather '' by the railway , and two Ruston 88 shunters ( RH 512572 is in service , RH 398616 is being used for spares and as a static display ) . The line operated two diesel shunters , one a Drewry shunter ( works number 2566 , current number D1995 ) , named `` Heather '' by the railway , and two Ruston 88 shunters ( RH 512572 is in service , RH 398616 is being used for spares and as a static display ) .