Hi I'm new here and brand new to PWC (all watercraft, actually). I just bought a pair of 2005 GTX models, one is NA I think 155 and the other is supercharged I think 215. I honestly don't know a lot about them, we have been trying to get some skis all summer and right now they're next to impossible to find. A buddy was selling these, I did some quick Google searching and they seemed to be good models. He gave us a really good deal so we bought them. They're relatively well maintained, not excellent. Oil changed every season, spark plugs, flushed, washed, that's probably about it. Overall they're pretty clean. The supercharger was replaced not long ago also. The NA ski will start but he said it won't go above 4k rpm and gives a code but he didn't get the code. I haven't put it in the water yet. The SC one cranks but wont fire. They have about 200 hours on them, maybe 200 something I forget. I plan to change the fuel filters as I read they don't last but about 100 hours. Will do oil, plugs, the typical stuff. I want to get them running before I dive into further maintenance, etc. Both have good compression, 120 psi on the SC one and 160psi on the NA. I'm sure I'll be asking for more help, I'm very mechanical but first time touching a PWC. I've read the owners manual front to back, have a service manual, and have been searching on forums a lot. My first question is one that will get me flamed....lol. oil for the SC one. I did see all the threads about it. Owners manual says use conventional oil, some sources show certrain synthetics are ok, amsoil has the tech bulletin for their oil, etc. My question mainly is that I decided to go with the amsoil four stroke marine oil, but they don't offer it anymore. It changed names it looks like to amsoil marine oil. This oil is JASO MA which I didn't think was good based on their chart in their tech bulletin. The old oil was MA2. Trying to get some clarification. I assume with the SC recently rebuilt it doesn't have ceramic in it anymore but don't know for sure. Thanks in advance, dying to get these on the water! Forgot to mention also they ran last year, set up over winter and then are not running. Being they came from a friend I trust they were running fine last year.