Sea star fluid, the bleeder hoses came with the boat. I'll try bleeding the system again this year. Went through this last year , hoping for a permanent fix. Perhaps l didn't remove the air bubbles completely.
My 180 sportsman is steering hard.l have tried adding steering fluid and turning the wheel to get air bubbles out. I am missing something like the air bubbles are recirculating. Does the pint of steering fluid need to be vented?