by breakwellmz » Tue Mar 05, 2024 3:35 am
Hi.
Messy! That could still just be down to a simple (and cheap) water pump seal, rather than something deeper like a head gasket, which is pretty unusual.
Personally. I would flush/clean it all out, fit new pump seals and oil filter, fill with cheap oil, and run it. Get it good and hot, and check/maybe change oil again.
They are all standard Yamaha parts, no need to look for MZ specifically.
Good luck.