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Lucky_Phill
02-01-2015, 05:18 PM
Took the Yamie out for a spin into Moreton Bay the other day.

Back at the ramp, after beaching it... and backing the trailer down. I started the ski and noticed smoke and could smell it...although it smelled more and overheating smell rather than an oil smell.

Anyway, get back home and go to give it a wash and flush... and when I start it, the smoke appears again. And I heard an alarm..no idea what it was.

Turn it all off and check oil level.... It reads over full ?

I waited a while and started it again...no smoke. So I give it a rev and some smoke and I hear a small clunck sort of sound coming from inside the engine bay.

I washed it and cleared the weed that was caught in the intake. All seems normal.

I haven't tried to restart it today. The engine was serviced about a month ago and I have done about 6 hrs since. 5 in fresh water and 1 in salt.

Obviously I have ideas on what's doing, but wondering if anyone else has thoughts.

I will get it back to tech to check ( pun / rhyme intended ).

I did a interweb search and found that the oil levels can be an issue and overfilling is a common problem.

My Ski is a 2008 VX Sport Yamaha ( 110 hp 4 stroke )

My initial thoughts are that I got a lot of weed caught in the intake and caused some over heating which thinned the oil, letting it slip past the rings when stopped and on start up, burnt the oil ????


LP

Lucky_Phill
02-01-2015, 06:16 PM
Well, I started the VX and ran it for 30 seconds. No smoke...no noise ???

LP

mattooty
02-01-2015, 06:45 PM
I reckon the weed was your #1 problem. I'd keep a close eye on it though as it may have started an overheating issue that could have done damage.

kind_cir
02-01-2015, 07:15 PM
Have heard overfilling oil can cause oil pump failure, but I don't know the reason why.

I would say you got it hotter than you normally do, and because the oil in the sump was slightly higher it would cause excessive windage in the sump. The crank would be dagging in the oil and splashing more to the bottom of the pistons then it was designed to. Oil control rings on the bottom of the pistons are designed to scrape the cylinder walls clear of oil on the down stroke. Excessive oil via windage combined by thinner hotter oil and those rings aquaplane if you like in that oil and not scraped off. Therefore it is burnt in the combustion process causing the smoke.

I was an Engine Reconditioner before I was a Painter Phill, so that is my take on it.

Lucky_Phill
02-01-2015, 08:20 PM
That sounded pretty technical, but I sort of understood it and that makes sense to my layman experience with motors.

I am feeling more confident it was the large amount of seaweed I collected / ran over on the return trip causing a overheating problem.

Thanks


LP

kind_cir
02-01-2015, 08:42 PM
You will just have to take it out again to see if it continues. Better take your rods too incase you have to wait for it to cool down. Can't have you out on the water just floating around, that would just be plain silly.

spottymac
06-01-2015, 07:54 PM
Have you checked the oil level on the dipstick,
Too high of an oil level allows the crankshaft and other components to agitate the oil and cause the formation of bubbles or foam. This foamy oil may cause a drop in oil pressure and lead to activation of the low oil pressure warning system.
If the FX 1600 has been over filled the oil can blow up into the air cleaner and they don't run to well, See video

https://www.youtube.com/watch?v=PFHuWyC86b8

Your Jet ski is a VX which I think has the same oil set up but a different carbys and air filter, check first,