Ended up working on the ’90 yesterday (Thursday). I put the new battery in it and it started up. It was pretty rough to get it started and from there it ran really rough. I actually had water hooked up to it and everything.

I had it run for a good 5 minutes at what I felt was idle and then started to rev it up. That’s where the issues started to happen. When it was reved up at higher speeds, it started to backfire through the carborator. My Dad and I decided that it was the rotary valve timing that was off, and needed to be timed correctly.

Now I’ve found two different ways for setting the timing. One way was the shop manual way and the other was found on the forums at stbonthweb.com. The forums guide pointed out not to do it the way the shop manual said. Seeing that I didn’t have a timing degree wheel, which is needed to do it the forums way, I tried to set it correctly according to the shop manual. After setting it the way the shop manual said, it was near impossible to get the jet ski to run. We did manage to get it running once, but it was running super rough and would not idle without dying.

I’m calling around to different jet ski locations today to find out if they have a timing degree wheel for sale. I’m going to try setting the rotary valve timing as the forums says this time.  So far, the two places I’ve talked to said they need to order the part (which I would just do at stbontheweb.com for cheaper).  I have one more place to try before I just order and wait.

On Monday, we took the SPX out to the Greater Miami River to test to see how it did on the water.  Up to this point, we were only able to verify that it worked by running it out of the water.  From past experience, we knew that because it works out of water does not mean it works in the water.  It ran GREAT.  That little thing has a lot of power (compared to our old Wet Jet).  We ran it for about an hour with no problems at all.  The only issue that we had was that it kept bouncing in the water, even the there were no waves.  This only happened when both of us were on it though.  Side note, the river still makes everything it touches stink horribly.

On the ’90, we changed out the starter on it after we tested the SPX.  From looking at the old starter, it was definitely bad.  Not sure if that was the only thing wrong with the jet ski though.  We didn’t think about charging the batteries before I showed up at my parents, so the battery only had an hour charge on it, which really wasn’t enough to try to get it started.  I’m going to head over Friday after work to work on it a bit more with a fully charged battery.