okay so im baffled.

So my 89 heritage started to leak fuel out of the overflow tube one day with the bike off after being started. I rebuilt the carb with new gaskets, or-rings, cleaned the slide and took the burrs off. New accel. pump diaphram, and replaced the float needle. Cleaned everything squeaky clean. I put it back on the bike. Fire it up and let it run for a minute or two. Shut the bike off and it starts to leak out of the overflow again.

I pull it back off the bike. Check to make sure the floats not filling with fuel. Check the float pin size and make sure the float towers aren't egged shaped. Double and triple check the float level. I even brought it into work and used a granite surface plate, sine bar and joe blocks to get the 15-20* angle. Put it back on the bike and does the same thing.

I pulled the carb off of my '93 fatboy. which does not overflow and it does it on the heritage.

My question is:
The bike is an '89 and I have read that alot of people shut the fuel off at the petcock (which stops the overflow) on bikes with non vacuum petcocks. The bike never did this before until one day. The fatboy has the same petcock and it dont overflow. Im getting frustrated with this issue. Cant anybody shed some light on this issue for me?

 

I always used the fuel shut off on any scooter that had one, just for safety sake. Have you checked the seat for any signs of a burr or possibly a flat spot?

 

no i haven't yet. I'm just confused on why its doing it on one bike but not on the other with the same exact carb.

 

Check your tank vents...it's possible your building pressure. Have you shut the petcock off and checked it that way.?

 

also might want to insure that the float hinge tabs are at 90 degrees to the float. had this happen and it would not shut the valve completely. did you put on new hoses? may have some debris getting into the bowl from old hoses, dirt in tank, and rust from the new gas. just some thoughts.

 

I would assume that you have already done this, but do you know if the float valve is actually working?

If it is seating and sealing, then I cannot see how your carb could overflow from the bowl...

 

Even if the petcock is defective, the float, needle and seat should prevent overflow. You need to verify needle and seat are sealing and check float for being adjusted or being heavy.