[Scott-Ohio]

Thanks again slls, I think you replied first to my last prob with this Malibu--trapped air in cooling system after flush/refill.

I'm curious about what thoughts you might have on what might be causing this problem or the process I'm taking to resolve it. I.e., would you follow the steps I have so far or take a different approach to diagnosis/resolve?

I've been trying to pry off with needle nose pliers, but will go try the 1/2" open end wrench now.

Thanks again, Scott