Serious Engine noise.

[Xstar]

I was on the lake today cruising at about 5500 RPM. The engine started to make a loud clattering noise. So, I let off the throttle and it stalled. Then it was locked up,. The starter clicked then the dreadded BEEEP. . When I got it home I pulled the upper head off to view the pistons. Just for grins I tried to see if it would turn, Seemed to be "unlocked". It did, with no noise. Both Pistons were Cycling properly or at least what appeared to be properly. I put the head back on and fired it up. It started right up but that Clattering noise comes and goes almost like it is out of balance. about 3 seconds on 3 off. There was no debris in the cylinder. I figure this is probably bad, but no big deal, that is part of owning a pwc. I Just need to get to the bottom of it. Any help will be greatly appreciated. BY the way, what does PTO stand for?

[frankey01]

Re: Serious Engine noise.

I would not run it without figuring it out first. I would say run a compression test first then go from there. Make sure you have good compression.

[David3aces]

Re: Serious Engine noise.

Power take off....speaking of take off, take off the cylinder and you will find your problem......

[Bustoff]

Re: Serious Engine noise.

Sounds like the pistons got too hot and enlarged in the bore causing it to seize..Were the cylinders galled??

[flyboy31]

Re: Serious Engine noise.

I agree, don't run it, tear it apart......sounds like a definate engine seize or partial hydrolock(maybe). Run it again and you may be looking at a new engine all the way around.

[Xstar]

Re: Serious Engine noise.

OK, Ill tear it down and take a look... What should I look for? Cylinders look ok. No scoring or anything like that.

[frankey01]

Re: Serious Engine noise.

Before you tear it down you need to do a compression test with results needing to be pretty close to the same. You could have a busted piston ring or something like that that has caused you to lose compression in one cylinder and not seeing any scoring of the cylinder sleeve itself. If you have already tore it down then it will be hard to verify anything through compression and you may need to post some pics and let some of the experts take a look and see if they see something out of whack. But do not run that ski until you find the problem or you may need a total new engine.

[Bill O'Neal2]

Re: Serious Engine noise.

Now here is what probably caused your siezure of the motor. You did sieze the motor.
You should consider trading it to SBT for a remanufactored motor with a one year warranty ( or two years optional warranty).

Usually, a lack of fuel or oil.
Lack of fuel, is caused by clogged up fuel filters, possibly the ones that are in each carbureator. Rebuild the carbs.
Check the fuel selector valve to make sure it passes fuel in both the "ON" and the "RES" positions.
If lack of oil, it could be a broken cable or a broken oil line. Inspect the complete oiling system for leaks or a broken cable, ect.

Usually, one of those things is what causes a problem like yours, unless of course, the rusty bearings inside the motor came apart after sitting around all winter collecting rust on them.