"Ivan" wrote in message
...
I have two adjacent ceiling fixtures holding two 40W 48" fluorescent
tubes, both controlled by a wall switch. Sometimes, they go on
properly; other times they'll go on if their glass tubes are touched;
still other times they need to be rotated slightly in their sockets.
And sometimes they won't go on at all.

What should I check?

The fixtures are at least 18 years old, but do not have the little
starter cans that older fixtures used to.

If the bulbs are old, try replacing them. or just replace the ballasts with
electronic 2 light 32 watt units, and matching bulbs. They will start
instantly