rotor squeezed
 

Going to build me another motor for spare but when i opened the engine one apex seal was stuck and cant come out of the rotor, anyway i got the one apex seal out with a little force,was wondering if i can reuse that rotor by using a flat file to open back up the groove where the apex seal fits so that i can get back the correct clearence ,cant figure out why it was squeezed and it never even damaged the rotor housing.

what year/type of motor?

Its a series 6 1993 motor

well, i've resurrected dead rotors before - it's not fun and it's very time-consuming! yeah, you can open up the spaces to fit the 3 mm apex seals from the GSL-SE as long as everything else on the rotor is still in spec (the bearing, the gear, the dimensions, etc.) and also depending on how far the broken seal was pushed into the space around it.

i wouldn't advise just hacking away at with a file though, and obviously, you'll want to do all 6 apex seals. might be easier just getting used rotors. in fact that's my "official" advice - just get rotors!

they can get squeezed when the car overheats (also possible from detonation) basically the seal gets so hot that it swells up inside the rotor and then gets embedded when it jams against the exhaust port, and another possibility is if another seal breaks and jams against another good seal of the rotor as it's passing over the exhaust port. obviously, i can't tell which was the case with your engine.

oh yeah ... and i can't explain why it didn't damage the rotor housing either :D