Advice Needed: Yam 701 Starting To Smoke Too Much

I have a '95 Waveraider Deluxe 701. The waverunner has always worked great and
never needed any kind of tune-up or service. I have run Yamalube, flushed
before (To warm up motor a bit) and after (to clean) and done a good job each
year of winterizing the jet-ski. Last year for the first time I started to
notice that during flushing it was smoking a lot more-- almost a whitish smoke
and it would pretty much start to engulf most of the neighbors homes.

1. What would be the first thing that should be done? Aside from the regular
spray carb cleanings and new plugs/gap?

2. How long does the reed valve(s) last??

3. Last summer the machine ran great at 9 years OLD-- was able to top out at
its normal 54 MPH and over its lifetime I have run the machine mostly
full-blast to keep it cleaned out.

4. I'm almost afraid to take it to a local dealer as its value is bluebooked at
$2.500 and I don't want to spend $500 or so on it. What would an honest
mechanic do to this thing??

Thanks in Advance

Dave