Help needed flooded 2010 ninja 250

[ineedhelp]

ok so a mate recently bought a 2010 ninja 250 it was a project for us to fix up form him to ride

we did an oil change and replaced the filter

did a full carb clean and it ran fine up until yesterday

my mate when to start up the bike to keep it running so he put it on prime for about 2 minuets and attempted to start the bike he said it cranked twice before the battery went flat as he only has a 12v battery made for a 50cc scooter then he sent me a message say there was fuel leaking out of the overflow i told him to tap the carbs with the back of a screw driver but nothing happened so i went up there to give him a hand with a spare 12v battery i told him to connect the battery i gave the carbs a tap and it still was leaking he tried to start the bike but nothing i released he had connected the battery backwards so i fixed it but now the whole bike doesn't turn on the lights on the taco don't light up at all i saw fuel coming out of the airbox so i had a look to see what was happening and the air filter was soaked in fuel and after some googling i found he may have flooded the bike completely i looked in the oil window and it was full (i guess of fuel) also we took of the tank and i notated the petcock was leaking. i know he needs to replace something electrical due to the battery mix up and drain the oil i guess the cylinders are also full of fuel.

i am wondering is the bike a complete loss
or if it is fixable if so what are the steps we need to take to fix this
tldr: fuel in airbox, leaking petcock, fuel in oil, battery connected backwards, carbs wont stop pissing fuel.
the whole bike is flooded

did we connect the carbs wrong? i don't think we did as it ran fine when we put the carbs back in??

Please help
thanks -AB

[Triple Jim]

The leaking fuel was caused by leaking float valves, and if they're leaking fuel with the bike off, the petcock is also not shutting off.

I can't tell you what was damaged by connecting the battery backwards, but quite possibly some things like fuses and diodes, and maybe worse. You might talk to someone who's been though that before and see if you can get some information. The wiring diagram is in the manual, and it's also posted here in various places. I don't think the bike is a total loss, but the electrical repair could be non-trivial.

[ineedhelp]

we did a whole day of work on the bike and found out that the 30amp fuse was blown so we replace it and all the lights came back on so we did an oil change and the oil smell very strong of gas i don't think it would be a problem with the floats but maybe it run fine when we put the carbs back in is it posable we connected the carbs incorrectly and that's why fuel got in the air box? as this problem started when my mate put half a tank of fuel in it?

thanks

[Triple Jim]

Well, maybe @ducatiman has some additional information to offer, but I don't think carbs will leak fuel anywhere unless either the float valves are leaking or sticking open, or the float level is set way too high. When one of those things happens, fuel can get into all the places you're having it get into.

[ducatiman]

TJ-
both your posts nailed it, IMHO

now up to OP to perform a carb/petcock redo (using new consumables) including a wet test to positively confirm fuel levels (resetting if needed)

[ineedhelp]

had the carb hooked up wrong had the overflow run back into the carbs fixed it and now she runs fine

[ducatiman]

cleaned a carbset for a member recently......he reported issues, asking about fuel/vacuum piping providing pics for my thoughts. I couldn't see both ends of hoses, but the owner did report that when making "corrections" to his fuel piping, it now "purrs" (yes, he used that exact term), starting and accelerating perfectly.

I'll submit many others have messed up piping issues. I'll also suggest prior to disassembly using a paint pen to mark (using dot or numerical systems) to assure hoses are put back to exact factory locations.

[ineedhelp]

yeah she's now pissing fuel i know the i said it was fixed but i got some fuel too keep it running until my mate got new brake pads and i put about 500ml of premium fuel and over night she has flooded fuel in the airbox again i think the petcock is damaged and is leaking through the vacuum system and flooding the whole bike i think its the petcock because when on she leaks out as if its on prime do i redo the petcock with a kit or do i make my mate buy a whole new petcock

-Thanks
-AB

[ducatiman]

A petcock redo, using all parts within a correct kit, if done carefully, will fix it. Personally, I prefer to utilize a softer than stock diaphragm oring, after fully cleaning its sealing surface.

[ineedhelp]

where would he buy the proper kit for a 2010 ninja 250
is ebay a good place? how much should he spend?

-Thanks
-AB