Fuel leaking from air box drain hose. Halp!

[Tsugigas]

*sigh

Hello everyone, new here. After doing a lot of searching and reading on both this forum and others, and a lot of trial and error, I'm stuck.

A little history of the bike. '93 GS500E bought from my buddy about a month ago. Bike ran fine for a couple weeks, then started to have some idling issues. Pulled the carbs and cleaned them, noticed that the float valves were worn, a nice ring indent where they seat. Bike ran a couple days afterwards, with more idling issues to follow. Then started to leak fuel from an open brass pipe beside the mixture screw (pretty sure this is a CA emissions thing I've never seen it in any posted picture of these carbs. Please confirm in picture below, yes I know the float bowls are mixed up in this picture, POs fault, corrected now).




Battery had died from excessive attempts to start, tried charging with minimal luck. Load tested battery and it was shot. Bought a new Yuasa and threw it in.

Started it up after putting the new battery in. After a moment fuel started pouring out of the air box overflow, all down the driveway... 

So I bought two K&L carb rebuild kits, pulled and replaced everything, hoping it was just the carbs overflowing because of the worn float needles.

Started the bike and after about 30 seconds, fuel was pouring out of the airbox again... 

Pulled the frame petcock and checked the flow and gaskets, both seem ok. However I did notice that there was no spring on the vacuum side. I also blew into the carbs fuel line to be sure the floats were seating, seemed to be fine


My questions are, why am I dumping fuel from the airbox? Could the lack of a spring in the petcock be affecting this? What do?!  I can post pictures or videos if it will help.

Any and all help is greatly appreciated from this newbie, thank you for your time.

[jdoorn14]

When you had everything opened up, did you check the float heights? If you replace the float valves, you definitely should check the heights.

Before you pull the carbs apart again, I'd suggest checking the float height using the clear tube method others have described in the forum. The fuel height should be no higher than the float gasket. If it's higher on either or both carbs, you'll still get fuel dumped back through the overflow tubes.

Also, I know others here have found that (especially on older carbs), the float valves in the K&L kits don't always seem to seat or seal as well as OEM. Could be another possible cause.