how full is got will determine what you need to need to do for damage control. if water was up to the top plug in the trans, then you should probably change motor oil, and trany fluid. to change the fluid in the trans, you need to raise the front of the machine off the ground as high as possible. ( i run mine up the ramps to m truck so the front tires are on the tailgate and block the machine so it can't roll) take the top plug out. open a 1 gallon freezer bag and lay it in under the bottom plug. remove the bottom plug and use the bag to catch as much fluid as possible. set the machine back on level ground. pour 1 Qt ATF in the top hole and replace both plugs. (note: one plug is vented... this has to go in the top hole)
after that, clean the machine really well. pressure wash everything that salt water touched. then use dawn dish soap on a toilet brush to scrub everything you can reach and pressure wash it out again. once the machine is dry, it might be a good idea to spray as much as possible of the interior with WD40.
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