going from memory, I believe 550s had 130-150psi compression stock?(Reed motors were 175?)... Anything above 120 and cylinders match +-5psi run it.
Leakdown test
if the engine is turning over and has "even" compression, run it. You got it for free?
My buddy compulsively bought an unfinished, unregistered ski, and has about negative experience with any watercraft or just wrenching alone. the guy who sold it to him at the time basically said he didnt have time to do anything with it and bought it just how we saw it at the time. He got that along with a unregistered 440 that ran. His plans were to take that skis to Havasu unregistered, and i advised strongly against that because the Arizona sheriffs don't enjoy people with unregistered craft. Anyway he bought them for like 8 hundred bucks while i walked back to my truck. i had no idea he bought them till they started wheeling them out to my truck. they sat in has back yard for about a year and a half or 2 years.
i had initial interest with the 550 as something i knew i could work on but left it at that when i dropped them off as it showed potential for a decent ski with most all the parts on it {excluding a tank and a few straps and a battery). Then a year and a half or 2 years later i get a phone call asking if i want the skis for free. i told him id grab the 550 but he said i had to take both.
Ended up completely disassembling both skis to trash the hulls that was unregistered. The 440 engine and parts are on the marketplace now.
For giggles i looked for a 550 hull only that was registered and to my surprise someone was selling one with a pump, tank and some other cool bits like handlebars, drive cables, throttle cables. 300 bucks. is basically what im into it right now. starting to get some tire kickers on the 440 parts but ill easily make my money back on that 550 hull.
i was thinking today that i was gonna also re route the exhaust gas through the back like an SX reed model due to the noise, Im a diesel boat mechanic and iv never done any fiber glass, what kind of glass do people use in the PWC world?