Super Jet Melted rear piston

[Armored snuffy]

I don't know why I keep melting my rear piston. It happened at the end of last season and I thought I had figured out why. Then it happened again last weekend. It's a 2014 superjet.

B pipe (with recomended carb settings)
Ada head
V force reeds

This exact setup with carbs were on a 2004 superjet 2 years ago and I didn't have any issues for several years. I then Switch everything to the new motor and i start having issues. The crank feels and looks really good. Is it time to rebuild my carbs?

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[augustaf]

Yes, check your rear carb for debris/ shed cotton from oem filter. You may find debris in the strainer accessed after removing fuel pump section of carbs

 

[Kaup_921]

I kept seizing pistons till I lowered my compression. I was running 35cc domes and was blowing around 195 at sea level no signs of detonation. Check your carbs but if it was running fine before it went then you could look into this. Make sure you have the correct jetting 135 mains.

 

[Harbor]

That looks bad. Noticed your avitar says Anchorage Alaska. Just curious whats the water temp the ski is running in and what is the engine temp. In NorCal dual cooling and no reticfters is too
Much cooling. Good luck

 

[Armored snuffy]

I kept seizing pistons till I lowered my compression. I was running 35cc domes and was blowing around 195 at sea level no signs of detonation. Check your carbs but if it was running fine before it went then you could look into this. Make sure you have the correct jetting 135 mains.

Yep. 135 main jets. 35 cc domes. I am not that far above sea level and I was up around 180 compression. But I had been running this set up for several years without issue.


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[Armored snuffy]

That looks bad. Noticed your avitar says Anchorage Alaska. Just curious whats the water temp the ski is running in and what is the engine temp. In NorCal dual cooling and no reticfters is too
Much cooling. Good luck

Water temp is around 65 right now. I only have single cooling on this ski. I have been in anywhere from 40 to 75.


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