Also still has old gas in it wondering if I siphon it out ? And wondering if I can take it out to the water before carb rebuild and new fuel lines
Not worth roasting your motor. I used superclean, got it from walmart, let it sit for a minute or two then thoroughly rinse and scrub will get almost all the grime and junk inside out. Once you get the inside of the hull clean it should be pretty easy to spot where the oil leak is, probably the oil tank grommet.
Check compression on motor.
Follow carb rebuild sticky and follow exactly, only genuine mikuni kits, needles, and seats.
As you know, new fuel lines, also best to order a fuel selector, and fuel filter assy.
Do you know what kind of oil has been used in the ski? any tcw3 is a no no, if you don't know the color is a pretty good indicator on what type of oil it is. Either way I'd recommend ordering a new oil filter and some 3/32 tygon oil lines found on the rotary valve, with age the can become hard and brittle. Breaking off starving your motor for oil.
And yes, best to siphon out as much of the old gas as possible.
While you're doing all this I'd inspect your jetpump. Wear ring clearance should be paperthin, any more than that and you'll be experiencing some cavitation. Change the pump oil, order the orings, sealant, and a neoprene seal and you should be good to go.
