Rachael's second mention is in "Justice" (Series IV), when at Rimmer's trial Lister is aksed by Justice World if anyone has shared moments of intimacy with Rimmer; Lister responds by saying "only one, but she's got a puncture."
When Legion makes Rimmer into a "hard-light" hologram in the episode of the same name (Series VI), essentially giving Rimmer a solid body again, Kryten says that he has a "puncture repair kit on standby".
Rimmer later denied that he was intimate with Rachael, saying that it was "a lot of half-truths blown out of proportion". Lister said that Rachael had been accidentally exploded when Rimmer left the foot pump in, and went to run a bath. ("Dear Dave" deleted scenes, Series X)