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ZS Carbs and the Choke

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TR4

TR4

Jedi Knight
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I recently had an issue with my recently rebuilt carbs where they would perform very well and the choke operated normally but they were leaking fuel. I was advised to adjust the floats and have done that so the leaking has gone away but the choke no longer works and the car is hard to start and keep running until I can get it warm. Once it warms up, the engine runs great.

Would it make sense that I have adjusted the floats too low and there is not enough fuel in the bowls to allow the choke to work properly?

Phil
 
The pick-up tube or "jet" for the choke is about 3/16 higher in the float chamber than the main jet.
 
I believe they were leaking around the choke spindle. I would find droplets of fuel on on the attachment screw heads for the bowls and I could pick up fuel at the choke spindle when I pressed a paper towel against them. I am not getting any fuel leaks now that I have changed the float height.

From Poolboy's comment, it appears I may have adjusted the floats too low (or too high when measured upside down) so fuel is not getting to the choke fuel pick ups?
 
Not much of a seal around that spindle.
Chokeassembly.jpg
 
Looking at the Moss site -- I think the TR4 ZS is quite a bit different from the TR6 carb, esp with regard to the 'choke' (TR4 uses a 'starter bar').

In any case, if mine have a fuel leak my first thought is O-rings, not floats... but perhaps that was covered in the prior discussion that led you to adjust the floats.
 
Thanks Geo, I don't believe the O-rings to be the issue since the carbs were recently professionally rebuilt by Paltech. I also didn't get fuel drips on the adjusting screw but did get drops of fuel on the screws that hold on the bowls. I feel the fuel was leaking out past the starter bar and collecting at the screw heads. Now that I have adjusted the floats to 20mm, I am not seeing any leaking. The choke is rotating the starter bars properly but will not perform as needed.
 
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