Yamaha F4 low compression, piston rings stuck in groove

I bought a used 2015 F4 four stroke 4hp outboard for cheap, and the owner said it was hard to start even though he replaced the carburetor. Compression tests read pretty low, 30-40 PSI, which improved with some oil squirts. Checked valve clearance and it was good, eventually tore it down and found the culprit: compression rings stuck in the grooves. Absolutely no end gap on the compression rings; the oiler ring is okay and I removed it. Apart from that, cylinder walls seem very clean with low wear, and everything else apart from some gaskets is in good shape. Any recommendations on how to free these rings? I took a propane torch and heated them for a good 5 minutes but they still wouldn't pop out. Worst case I'll order a new piston and rings.

You will absolutely need new rings anyway so a good soak for 24h or so in something like WD40 then tap on the split line for the piston ring using a small screwdriver, they will pop open or snap, if they snap just work your way round doing the same thing.

After installing new rings and putting the motor back together, I was able to get her back up and running! Currently breaking in.

Ace, Good Luck.