Fuel leak

[viclava]

Ok, fellow KAt riders. I have this leak under the left outboard carb that seems to drip at the bowl drain screw. Now, I removed the drain screw, only to find there is no O-ring on it. Is this the norm? Furthermore, I noticed on the brass screw some wear(by that I mean the brass color is slightly worn off) I seem to get more when I run the bike of course, but I also thought it might be the rubber boot on the forward side of the carb that connects to the engine. Any thoughts out there???

[KatanaJim]

I dont think there is an o-ring on the drain ( Im sure I will be corrected if I am wrong, but I have my carbs off now and iI dont have them and the carbs dont leak so go figure!!!).
I would look at the bowl gasket itself as the culprit. It may cause the fuel to drip down to the lowest point on the carb (drain screw), so that it looks like it is comming from there. My 2 cents...

[kiba]

Re: Fuel leak

but I also thought it might be the rubber boot on the forward side of the carb that connects to the engine.

I would hope not! There shouldn't be any liquid fuel going through there... If there is, then you have problems (stuck float valve AND bad petcock) and will probably fill that cylinder up with gas!

/kiba

[Black_peter]

Chuck the screw in a drill and polish it with scotch brite..

[viclava]

Fuel leak

Black_Peter,
What's the reason for the polish job on the screw? Just to take any unseen roughness?? I appreciate your time to respond.

[md86]

You SURE that's where it's leaking from ? I had a leak for a while I couldn't track down . I SWORE it was the bowl gasket , then it was the bowl itself , then it was something else . Finally took the carbs off and connected the fuel line to the tank , stuck the thing on prime , and waited for the drips . Turns out it was coming from the inlet "t" deal . There's a little rubber sleeve in there that was done . Food for thought .

[The CyberPoet]

If it looks like it's coming from item #17 in this 96 Kat 750 Carb Diagram , swap the screw with another carb. If that doesn't cure it (and it probably won't), it's almost assuredly the O-rings MD86 is talking about (I think it's item #15 in this 96 Kat 750 Carb Accessories Fiche Diagram for your carbs). They wear out with age and crack -- and when they do, they leak minorly while the engine is running (but the petcock cuts fuel to the carbs when the engine's off if it's working right, so there is a limited amount that can leak in after the engine shuts off).

Cheers,
=-= The CyberPoet

[viclava]

leak

Personally I don't think it's the drain screw either. I just think it's running down to the lowest point which just happens to be the drian screw. Thanks.

[Special K]

Could be:

Drain screw
Bowl cracked at drain screw
Bowl cracked elsewhere
Bowl gasket leaking
Leak up above that

If you need another bowl or a drain screw, just pay the postage & they're yours!