Wankelteer

So, I just tried to start her on a fully charged battery. She sputtered in between 500 and 900 rpm, even though I was applying throttle. Then made a ping sound and quite. I think my baby is dead. Does it sound like my seals are blown? I guess I should test for compression, Just manually turning her over with the header off should give me an idea, right? Thanks for any input guys, looks like Im lookin' at a rebuild. This might be pricey