Leaking Float Bowl

Thanks to all of members of the forum who helped me out with my Air Fuel Mixture Screw questions that I had last week. now I have a new Carb related question. The Motorcycle I am working on is a 1981 KZ750 Four Cylinder H2. I've installed the (Kehin)Carb rebuild kit that I purchased from a Company recommended on this web site (Z1Enterprises). My question is, I have a small drip coming out of the over flow nipple on the bottom of the float bowl on the #2 Cylinder. My first thought is to pull the carbs back off and adjust (tweak) the floats on that carb only but I just wanted a couple of opinions before I take it back apart. Any advice would be greatly appreciated.

Thanks

Hmmm, are you sure that's an overflow nipple? I've got a 1982 kz750-4 H3 with Keihin CV34 carbs. My carbs don't have overflow, the nipple is just a drain for the bowl. If you're getting a drip, maybe the new 0-ring didn't seat correctly.

Are you SURE it's leaking from the nipple,and not the bowl gasket,or even the t-fitting(if you have one)?
Check around,higher than where you THINK it's leaking from,to be sure.
The leaking gas will form and drip at the low-point,but that may NOT be the source of the leak.I've been fooled before,so make sure it's not leaking from somewhere else.
Check in the higher regions of the carbs,and make sure the leak isn't travelling to where you think it's leaking from.

Wipe the bowls dry,and then use a q-tip to feel around...checking the q-tip periodically.

I watched it come form the Nipple. When I shut the fuel off (manual Petcock). It will drip about a tablespoon of fuel from that nipple only, over a period of a minute or two. Does anybody know if the copper tube running up the inside center of the float bowl is a over flow tube?

Just checked my manual and it does show an overflow tube for the 1981 model....sorry I questioned it.

I'm thinking that you'll need to get in there and adjust the float, sorry I know that's a pain, I had to pull my carbs 4 times this Spring. It took a month for my knuckles to recover!

Stevec6535 wrote:

... have a small drip coming out of the over flow nipple on the bottom of the float bowl...

If some crud is preventing a complete seal where pointed end of float needle fits against its seat, fuel can continue flowing into the floatbowl past the incomplete seal and on out the overflow.

Sometimes any such crud may be flushed away by opening the floatbowl drain screw, and allowing fuel to keep flowing through for a few moments in hopes of flushing away the crud.

Good Luck!

Some CV34 assemblies have brass tubes (overflows) and some don't. They connect to the drain. If the tube isn't cracked, the float height or valve needle/seat may be the issue. On the CV34, you can't change the seat so it needs to be cleaned. Last, if the oring on the drain screw is bad or the drain screw is worn (they often are), the drain will leak. Swap the drain screw from the leaking carburetor with one from a carburetor that isn't leaking to eliminate this as an issue.

I've got a extra set of carbs. I will swap out the float bowl and give it a try when I rejet.

Thanks