Carb Float Drain Leaking

[James0541]

Thank you to those that advised on my recent thread on carb pipe locations. Once I got them sorted the bike started without issue and ticked over nicely, first time in a year

But, after switching off the ignition the left carb float drain began leaking. I have replaced the drain screw as this was a little corroded, but no luck. Do I need I need a rebuild kit and can it be fitted with the carb in place?

I did restart the bike with the new drain screw fitted, but gave the carb a tap with a srewdriver handle, no leaking drain. After switching the bike off and restarting it began leaking again.

Thanks,

James

[clARky]

Yes to a carb service kit but you will have to take them off to do it properly. Sounds like the fuel needle on the float is dodgy and if original may have been affected by ethanol in the fuel.The new ones are ethanol proof.

[donnybach]

Yeah a good carb service as clarky suggests will do wonders. Get all the rubber seals changed and clean jets and she’ll be lovely.

[James0541]

Thank you both, I know what I'm doing this weekend

[James0541]

So, I have fitted a carb service kit to both carbs, and new float drain screws, but still the left float drain is leaking petrol. I have turned the drain screw the whole way in, no difference.

Should the drain be open like in the pic, or is there a rubber blank that goes over it?

Thanks,

James

[donnybach]

The drain plug doesn’t look like it has an o ring in the diagram on cmsnl. 13 euros. Drain the carb, take it out and see if there’s any damage to the seating or the plug. Maybe polish out any damage. For £13 I’d get a new plug anyway. Maybe it does have a seal included. Either way it’s a fresh face.
Might just be some crap left in there stopping it screwing home.

https://www.cmsnl.com/yamaha-xtz750-198 ... fv1419100/

[Duc_Rider_NL]

I had the same. After polishing the screw, tightened even more, checked it all. Finally there was a small hair crack inside the float chamber were the screw enters, so it kept poring out. Probably over tightened several times….