Re: 1995 sport jet motor- should I buy
I have a 95 Sea Ray SeaRayder jet boat with a 90 hp sportjet. We bought it 6 or 7 years ago. The 90 is a 3 cylinder, the 120 a 4-cylinder; the service manual is the same for both.
Because the engine is essentially a Merc OB powerhead on a jet pump drive, any mechanic familiar with Merc engines should be able to work on it.
That said, I would urge caution. We had starting issues a couple years ago and took it to a local marina for work. In retrospect, all it needed was a carb rebuild, but this mechanic focused on ignition - replaced the stator and most ignition electronics and never did address the carburetor problems. He put the wrong flywheel back on with no flywheel key, and failed to properly torque most engine parts he'd disassembled. As a result the engine self-destructed requiring a major overhaul (new pistons, rebored cylinders, etc) -- but we took it to a different marina we could trust for this work. In that rebuild, an oil injector was installed from Mercury that proved to be defective, so it's getting yet another rebuild right now. Be very careful who you have work on it.
If you search in this forum, you'll find many discussions on the plus and negatives of jetboats (for some, look for my posts).
My recent experience colors my thoughts, I'm sure, but knowing what I know now, I'd probably buy an outboard rather than a jet if I had to do it over. The primary reason, though, is the very poor gas 'mileage' of the mid-90's sportjets and performance (poor hole shot) less than I expected. I'm not sure the size / weight of the Mirage you're looking at. My SeaRayder is 13.5' weighing around 600-700# dry. Due to power loss inherent in older jet drives, my 90 hp is underpowered. I don't know how that'd translate for the one you're looking at.
Newer jetboats seem to have resolved many of these issues. Friends of ours have an '01 16' SeaDoo with much more power and fuel economy than ours.
HTH
Al