Gear problem

[Hank]

On my 1965 Skymaster raising the gear, normally the gear up light comes on, then the gear doors close, then the gear handle goes back to neutral. Lately however the gear up light comes on briefly then goes out and the doors stay open. Bringing the gear down and up again cures the problem, though sometimes it takes 3 tries. The doors close normally every time on the gear down cycle. Any leads I can give my A&P would be appreciated.