1998 GS500 motor in my 2007

[JoePerez87]

So I got a 2007 GS500F on a trade. The guy I got it from swapped in a motor and harness from a 1998. Everything seems to work however it's not wanting to fire. On its own. It will with some starting fluid but only fo a second then it will die. It still has the 2007 throttle cables/choke etc. I had to make a plat to get the return throttle cable to work with the 1998 carbs. It's still using the 2097 frame petcock also. Like I said everything seems good it's just not getting fuel. Could have the fuel lines hooked wrong? I'm stumped. I'm gettin fuel through the lines I put in a couple inline fuel filters so I can see the gas. Any ideas?

[Bluesmudge]

Do you know if the bike had been sitting before you purchased it? Carbureted bikes and GS500s in particular don't like to sit. Check the tank for rust to find out if its going to keep clogging fuel filters after you fix the problem.

If you open the carb drain screw does fuel come out? That would mean the issue is probably not the petcock and more likely the idle circuit or choke operation. Could be as simple as clogged idle jet or two from old gas.

You may just want to replace the petcock, fuel lines, and rebuild the carburetor to eliminate all the potential problems rather than trying to diagnose it exactly. You will likely need to clean the carbs anyways.

[JoePerez87]

Thanks for the reply. The bike was sitting for awhile. The carbs were clean. I'll take them off and clean them again. There was rust in the tank but that is now gone. I cleaned it along with putting new fuel lines on. I need to find a diagram for the hose hook up for these carbs. I feel like there are vacuum lines missing.