The dark bar is the hoz blanking pulse. The vert is stretched and maybe rolling.
Start at the hoz AFC & if it is rolling also, look at the sync sep stage.
With ANY old JA solid state B&W they have bad small 'lytics. Even
50 yrs ago recapping the hoz & vert would fix 90% of them. JUST the
electrolytics ! When the hoz is fixed odds are the width will be normal.
GL & keep us posted.
73 Zeno
LFOD !