BETTY WHITE is proving you’re never too old to be a cougar!

A source says that the 91-year-old Emmy winner recently got flirty with her old pal Gavin MacLeod – who’s just 82 – when the two reunited to film an in-flight safety video for Air New Zealand. Although it may have been a tongue-in-cheek “pass,” the spunky senior even invited her former “Mary Tyler Moore Show” cast mate to join the “mile-high club” with her.

According to the source, when Gavin reminded Betty about his longtime wife, Patti, she quipped: “That’s your problem. I don’t have a lot of time and you have a sweet ass!”

The source added that Betty was so excited while waiting for longtime friend Gavin – who also starred as the “Love Boat” captain – to arrive on the set, she had goose bumps.

 When Gavin finally got there, the two hugged, filmed a few takes – and then Betty made her move.

“They were sitting next to each other, laughing about something funny that happened in the old days and then, out of nowhere, Betty reached over and put her hand on Gavin’s knee,” said the source.

Then, the longtime funnygal “began stroking Gavin’s cheek and leaned in to kiss him. Gavin tried to get away, but Betty grabbed his arm and yanked him back toward her.

“She cooed ‘COME ON, GAVIN, DON’T BE COY. You’ve been hot for me for 40 years. Well, now’s your chance. Ever hear of the ‘mile-high club’? We’re looking for new members!’”

Fortunately, the director broke up the encoun­ter when he called them back to finish taping.

“When the shoot was over, Gavin couldn’t wait to scoot off,” the source revealed.

 “But Betty had the last word. She winked at him and said, ‘Take care of yourself, hot stuff!’”