IDoSeaDoo
Well-Known Member
Hello all, I'm new to this Forum and hope someone out there can help my desperate situation. I recently bought a 97 SPX (my dream jet ski since I was 14). It ran great for a few weeks until my wrist pin self destructed and killed my engine. I made the mistake of buying a used one off craigslist, the owner of which claimed it ran.
After receiving it and replacing the wrist pin bearings in it, I reassembled it and put it back in my ski. The previous engine ran w/ no issues, carbs were fine, fuel lines/selector switch were fine, everything worked.
The new engine has compression of 135/140. I replaced the rotary valve shaft gear, as the old one had way too much play. Sure enough, it seemed pretty chewed up. Rotary valve has proper clearance and is timed to 147deg BTDC (according to manual).
Problem: The new engine starts and runs on the trailer, but when I try to open up the throttle really fast from idle, it sort of stumbles, revs and smokes blue. In the water, I managed to get it started, it ran, never got up to full speed, and then started to bog. Now it won't start in the water. Occasionally, it will almost start, then sneeze a backfire (sounds likemaybe through the carbs). On the trailer, it cranking it, it coughed out 2 liters of water once. Starts on trailer, but smokes when revving. Also, I noticed that it has a tiny little water leak from the exhaust pipe at the plug weld (leaks a little jet into the hull).
Is this ski sucking in water into the exhaust and choking itself? Are the crank seals blown? What are the symptoms/effects of blown crank seals?
Please help, this has been a nightmare for me for like 2 months now.
After receiving it and replacing the wrist pin bearings in it, I reassembled it and put it back in my ski. The previous engine ran w/ no issues, carbs were fine, fuel lines/selector switch were fine, everything worked.
The new engine has compression of 135/140. I replaced the rotary valve shaft gear, as the old one had way too much play. Sure enough, it seemed pretty chewed up. Rotary valve has proper clearance and is timed to 147deg BTDC (according to manual).
Problem: The new engine starts and runs on the trailer, but when I try to open up the throttle really fast from idle, it sort of stumbles, revs and smokes blue. In the water, I managed to get it started, it ran, never got up to full speed, and then started to bog. Now it won't start in the water. Occasionally, it will almost start, then sneeze a backfire (sounds likemaybe through the carbs). On the trailer, it cranking it, it coughed out 2 liters of water once. Starts on trailer, but smokes when revving. Also, I noticed that it has a tiny little water leak from the exhaust pipe at the plug weld (leaks a little jet into the hull).
Is this ski sucking in water into the exhaust and choking itself? Are the crank seals blown? What are the symptoms/effects of blown crank seals?
Please help, this has been a nightmare for me for like 2 months now.


