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Thread: XR1800 Help!!!

  1. #1

    XR1800 Help!!!

    Melting pistons after engines take on water. 2 pistons driver engine. 1 piston passenger engine. need help!!!


  2. #2
    Dirty Sanchez's Avatar
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    where is the water coming from? You need to resolve that issue first dip it the water and see where it's coming in. I had 2 leaks on mine

  3. #3
    Is it almost winter yet??? ProXR 440's Avatar
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    Define "melting" pistons. Did the motors injest water or did a water leak in the cooling system cause the engines ran too hot?

  4. #4

    XR1800

    Because i left my jet ports unlocked in the rear, in about one minute half the boat was full of water. So the engines sucked in water through the intakes. Went home cleaned it up, new plugs , no more water.......Next day maybe within 5 minutes driver engine looses power. NO Compressoin. month and a half later after i fix with no other visible problems. Other engine middle cylinder same thing. 2 weeeks later back to the driver engine, different piston then the one i fixed, but same problem.
    Melting...................The first one blew a clean hole between the piston and rings and out the side......second one BLEW UP- piston broke in half/skirt on bottom or cylinder broke off. Alot of metel hitting the top of the piston. Third problem Same thing but clylinder mainly damanaged and black at the exhaust hole but power valve looks fine. piston wore everywhere.

  5. #5
    Happily Self-Employed WFO's Avatar
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    pics, pics

    anytime you injest water you run the risk of crankshaft bearings rusting and possibly bending rods or even knocking a crank out of phase (water wont compress very well)

    better pull both motors and go thru them bottom to top

    .02

  6. #6

    pictures of melted pistons

    Pictures are in sequence. Piston #1, Piston and cylinder #2 from oppisite engine, and piston #3 from previous engine again. All three within 3 months after the water was injested.
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