Rebuilt carbs leaking like a sieve

[chef1366]

You're filling your float bowls too much or are leaking from the float needle and seat.
That is your main air jet and is directly connected to the main jet. When the bowls overfill that is the first place it come out.
You either have torn O-rings on the float seat (inlet valve), the float adjustment is way off or the needle and seat are not sealing.
Check for a ridge on the tip of the needle that you can catch your fingernail on. Did you happen to mix up the old needles and seats? They wear as a pair.

[oblique]

Thanks for this. It never occurred to me that the seats might be worn as well - I do indeed have new needles against old seats. Much appreciated.

[JTGS850GL]

I'd replace all 4 seats with new needles. Lots of aftermarket options as the OEM seats/needle assembly is VERY expensive.

Here's where I got mine:

http://www.partsnmore.com/

[chef1366]

I have some good stock needles and seats I'll put in the ultrasonic cleaner and send to you.

[JTGS850GL]

Now that's even better.

[branumhawk]

I have some good stock needles and seats I'll put in the ultrasonic cleaner and send to you.

They did not leak before and after a second tear down they gushed. Fuel tees are obvious in location of leak. Your problem is in float needles or o ring on the seat insert. Make sure you put the pilots with o oring and little washer in as called for. Lightly lube o rings and gently push in the seat. Take a break, drink a beer if that helps and start over from the beginning paying strict attention to what your doing. The float height didnt change unless you got really rough with stuff. Tap on bowls with wooden screwdriver handle lightly as gas fills them up. Aggravating for sure, it will solve itself in the same in way it came Good luck

[oblique]

The only thing I changed in the second rebuild (besides the float needles themselves) is that I took a rotary brass wire brush attachment, in the shape of a spearhead, and at low speed got down into the orifice of the seats themselves to get a good clean contact area for the needles.

I did check the pilots and they were good. Everythings still clean with fresh o-rings and washers as before.

[JTGS850GL]

You probably scratched or distorted the seats when using the wire brush. Now I'm sure you need all 4 assemblies replaced.

[86gs1150e]

I am glad I seen this post I had a similar concern I am planning to replace all needle and seat valves my question is I have read on previous posts not to use aftermarket float components
stick with oem example partsnmore can get 4 sets price of one compared to oem was wondering anyone using these any concerns or opinions any info would be great Thanks.

[branumhawk]

I re read from the beginning and I think the rotary wire brush bored out your seats. Power tools and carbs don't play well together.

[oblique]

The wire brush was used softly and for a split second to clean up the seats. Frankly the needles are conical and I dont see how this wouldve prevented at least a partial seal. The carbs didnt drip, they gushed.

[Newell33]

I went through the same exact issue on an identical bike. I had the carbs on and off numerous times, and made several float adjustments. After it was all said and done, the culprit was in fact the aftermarket bowl gaskets. The gaskets were thicker on the sides, causing the floats to hang up when the bowls were installed. I remember making sure the floats moved freely, but I never even thought about the bowl gaskets until another member mentioned it. I ended up trimming mine as I didn't have immediate access to OEM gaskets. Note that I had to trim them considerably to get the leaking to stop. Once I got them adequately trimmed, the leaks stopped. The aftermarket gaskets aren't easy to trim, so do yourself a favor and get a set of OEM gaskets.

Good luck!