2001 Yamaha XL 700 waverunner

[SRSx3]

Acquire a 2001 Yamaha waverunner XL 700 with a good deal. Last ski activities was 4 years ago, and change the sparkplugs, put new oil since oil is empty, put a fuel stabilizer, engine turn over then it starts but noted a bogging engine and starts good but noted a black fluid coming out from the engine grate and smells like fuel and oil in it but black fluid coming out a lot of them in the intake grate with water running for 5 mins from the hose. Didn't test the ski yet but did check the compression, then noted only 70 PSI on front cylinder and 150 PSI on rear second cylinder. I know I need to rebuild the carburetor, and probably the top end of the engine. Any ski experts out there who can help me with this Yamaha ski with black fluid discharge coming out from intake grate. Thank you for your help.

 

[Cobra Jet Steering LLC]

Hmmm weird .. NOTHING should be coming out the intake grate.
The ride plate under the pump may have trash coming out the exhaust and exhaust can also exit the pump nozzle as the cooling system is all interconnected and this is common.
First the engine will need to be rebuilt because 70 psi is not going to work AT ALL.
Second you should have totally cleaned out the fuel tank as this fuel being 4 years old is just not going to work but it will gum up everything. It's more like stale turpentine now.
If you only have a warped head and blown head gasket you may only need to SURFACE THE HEAD and replace the head gasket, but if water was in the engine and the rings went bad or the bearings on the rods or crank went bad you need to do the entire rebuild job , or replace the engine.
To see if there is play in the connecting rods without disassembling the engine you can remove the spark plugs , then rotate the engine watching for the piston to come up to the top of the cylinder, next continue rotating the engine in the same direction and when you see the piston start to go downward in the cylinder STOP and use a screwdriver in the spark plug hole to push down on the top of the piston, if you feel a CLUNK when you push on the top of the piston that is bad and there is an issue with a rod or wristpin bearing.
If it is tight you are probably ok.
As for the head if it was overheated and the head warped it probably has water damage in the cylinders and on the pistons so what may have been a good deal ends up being a lot of work on a ski that is not worth very much even in good condition so before investing a lot of money and time in it look into what it would sell for if it was in good running condition because next is the possibility of servicing the pump bearings , liner, impeller ,battery and cables to deal with.