Leaking SII zenith carb

[Craigegg]

I’m having a hard time trying to stop a leak from the zenith carburetor body. It looks like it’s leaking from the linkage at the lower body of the carburetor but not sure .
Anyone have any suggestions?
Thanks.

 

[alpine_64]

The zeniths have a habit of weeping. Also wearing out the area in the body where the throttle spindles pass through.. Bernd in Germany is a good source for info and parts...

@bernd_st

 

[Craigegg]

Thanks

Sounds about right, I had change the O Ring in the needle valve thinking that maybe it, didn’t make any difference.

 

[Craigegg]

Hi Bernd, here are some pictures of my carb

 

[husky drvr]

C,

There's a possibility the leakage is at the thick insulator gasket between the base plate with the throttle shaft and the carb body.
The fuel/air passage(s) for the idle mixture and progression holes travel through the gasket to the base plate. There are two screws that attach the base plate to the body but they are only accessible after the carb is removed from the manifold. This illustration is from WSM 124 and is of the WIP 2 design carb. The WIP 3 carbs are a bit different due to a design change of the idle mixture circuit, but still have fuel passing through that gasket. (small inset at top right)

Just something to check,

 

[Craigegg]

I’ll check, but it seems to be leaking just above that. Thanks all for your input

 

[bernd_st]

Thanks for the pictures.
Yes, your interconnection throttle rod is fuel stained. Before attacking the throttle spindles however I would check whether your threaded fuel inlet isn't leaking. As it looks your fuel line holding screw is rather far in. Can have 2 reasons : Either you overtightened to get a good seal while your fuel line sealing brass "olive" is deformed, or your casted fuel inlet section on the Zenith is hairline cracked. Worthwhile to do a thorough inspection at first...

 

[Craigegg]

I will take it off and do a inspection, I appreciate the input I will let you know my findings.

Thank you for your help

 

[Craigegg]

Hi Bernd, in response to your reply I inspected the fuel line and inlet to the carb I didn’t notice any cracks or splits. I did find it seems to leak only when the throttle opens. What does that sound like?

Thanks

 

[bernd_st]

It sounds as if the throttle spindles are badly worn. However we need another evidence:

Can you rock the spindle in open / closed position to check for extensive play ?

 

[Craigegg]

Hi Bernd
A better set of eyes discovered on the fuel line fittings that are questionable,some small nicks. If I wanted to change the fittings I’m not sure if they are available or replaceable. Cutting the fuel line to install a fitting with a compression ring would make it to short.

Any options.

 

[Craigegg]

Any one else that would like to chime in on the fuel line fittings please do.

Thanks all

 

[bernd_st]

The fittings mean the threaded brass screw plus the "olive" are available. New fuel linings can be brazed/soldered, but up to your skills...