Flip lever radiator caps are the spawn of the devil- - - -has anyone ever seen a pressure cooker with a flip lever on top? Imagine a pressure canner that holds 3 gallons of water, at a temperature above the boiling point, that suddenly gets the pressure released. That's the equivalent of lifting a radiator cap lever on a hot engine. If the coolant is hot enough to need pressure to keep it liquid, the only way to check or add coolant is to wait. When it's a cold engine, then open the cap. I'd recommend about a six pack's worth of time, at a minimum. Anything but Bud Light!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!