1982 Yamaha Seca Turbo (XJ650LJ) Had the carbs

Without knowing the year of the bike, the following link is about the best that can be done.
Fuel Pump schematic Yamaha Xj650lj 1982

Clean/rebuild your carbs and then synchronize them...or take it to a professional who has the tools and synchronizing gages.

you either have a major air leak(that you would hear) or the turbo is getting a bit old.Also check the turbo oil lines.Make sure they are feeding so the turbo can spin.Hope this helps

The carbs overflowed into the crankcase, happens every time a carbed bike sits for a long time. The carbs will need to be cleaned

When the carburetors over flow enough to fill the exhaust, It is possible that the gas also went into the cylinder and flowed past the rings and into the crankcase. With the engine overly full of gas and oil you could easily pop a seal or blow out a gasket. Check your oil level. If it is too full , change the oil, it will not lubricate properly with all the gas in it. Check that your shaft seal has not popped out. Check the air filter, the breather may have blown oil and gas all over it when you started the bike. Empty your pollution tubes behind the motor( they will drain the air box). Get in the habit of turning your fuel petcock off when not riding. This gas flooding happens randomly in certain models but can happen to any one.

Autozone may have the manual for your specific bike.

visit this site and contact chacal he has a lot of stuff for xj bikes www.xjbikes.com

Hey pal, this bike probably sat 4 awhile right?
If your idle jet is clogged it won't idle, the carbs need to come off, turn them upside down and remove bowl to see the jetsIf this is too much then take it to a moto mech