gas leak at float bowl drain

I haven't taken the carb apart. Not sure if it is easy on these. I just did work on my my Honda CRF 250X recently that required carb removal and it sucked really bad getting that thing back in place. So I'm not excited to rip into it if I don't have to. It looks like maybe gas is leaking from the bowl drain at the bottom of the carb, but I don't think there is an o ring there. Is there an explanation that I'm overlooking? I suppose it's possible it is leaking higher up and running down to that level and pooling up, but I thought I would start there first if anyone has a suggestion. Bike is a 2003 we acquired late last year. Thanks

17 minutes ago, dogeddie said:

I haven't taken the carb apart. Not sure if it is easy on these. I just did work on my my Honda CRF 250X recently that required carb removal and it sucked really bad getting that thing back in place. So I'm not excited to rip into it if I don't have to. It looks like maybe gas is leaking from the bowl drain at the bottom of the carb, but I don't think there is an o ring there. Is there an explanation that I'm overlooking? I suppose it's possible it is leaking higher up and running down to that level and pooling up, but I thought I would start there first if anyone has a suggestion. Bike is a 2003 we acquired late last year. Thanks

What bike? E, SM, S? What carb?
Mikuni BSR36 or FCR39 

The drain screw has no O ring or gasket..its is just a  tapered screw / seat screw to body 

It is an "S" with a stock carb - looks like a BSR. I just checked it again and it is leaking above the bowl drain - I assume it would be the float bowl gasket where the bowl connects to the carb?

Where is the gas pooling and does the oil smell of gas? Do you have the stock fuel peacock or a manual-off one?

Edited by shuswap1

It has a aftermarket petcock that is manual. I think it is just old gaskets on the carb. Can you buy a gasket kit rather than the whole rebuild kit? I don't need jets. Wondering if the carb comes off easy.

1 hour ago, dogeddie said:

It has a aftermarket petcock that is manual. I think it is just old gaskets on the carb. Can you buy a gasket kit rather than the whole rebuild kit? I don't need jets. Wondering if the carb comes off easy.

Let the carb fill, and then disconnect the fuel line, clean carb well & dry , place clean dry paper towels under carb on top of motor and let sit overnight ...Make sure its not gas dripping down from the fuel petcock.

Yes you can get a bowl O ring https://www.partzilla.com/product/kawasaki/92055-S058?ref=806390c88505c7cba455c6307b45d9374e3b41aa 

While your in there replace the O ring on the needle seat https://www.amazon.com/gp/product/B00NQZRF9U/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

 

Thanks alot! The petcock is kind of a cheesy aftermarket one. I should consider something else there too.

Edited by dogeddie

Don’t be too quick to assume it’s the float bowl gasket leaking, not unheard of but not common, in my experience. Not always easy to spot the exact source of a leak.

As Erik mentioned above, change that o-ring out. If your o-ring is original it will be shot and will cause similar symptoms to what you describe. You didn’t say if the oil smells of gas?

Edited by shuswap1

I just changed the oil last night so not sure how accurate that would be. Are you talking about the needle seat O ring?

Do you just turn the carb to remove the float bowl or take it completely off on these bikes?

Edited by dogeddie
8 minutes ago, dogeddie said:

I just changed the oil last night so not sure how accurate that would be. Are you talking about the needle seat O ring?

Yes they get hard and shrink (there is a partial joke there someplace) ..super common. From the OEM, the O ring is only available in a set of needle, seat and O ring.. But almost always the only real issue is the O ring. 
You can buy one for about $2.25~$2.70 plus shipping, 

or you can buy a pack of 10 for $3.00 and free shipping (Amazon Prime) and have spares, as it will need replacing again.

https://www.amazon.com/dp/B00NQZRF9U?tag=viglink20633-20

Or find one local,, good luck with that 7.5 mm ID, 10.5 mm OD, 1.5 mm Width   there is a 1/16" O ring that kind of works, and I used it many times before the proper one was sourced and now readily available.  There is no reason to struggle to install the wrong size O ring now.. buy a pack of 10, use one , have 9 spares, install a new one every other year or so.  

Just going through this with my bike now (here), Erik was super helpful in sorting it all out. I currently have 50 of the needle seat O-rings on route (smallest amount I could buy on amazon at the time). So I will have lots of spares if you need one. 

Edited by CT2

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