Fuel leak - SU carb, any ideas?

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Nissanman
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Re: Fuel leak - SU carb, any ideas?

Post by Nissanman »

Usually, the cause of over flow is debris trapped in the needle and seat valve.
Well that has been my experience anyway.
I'm sure floats that turn into sinks is also an issue but I'm still using the original brass jobbies and never had a problem with that.
Barring the above you should never see fuel exiting those tubes IMO.
Nissanman, just trying to help.
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spl310
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Re: Fuel leak - SU carb, any ideas?

Post by spl310 »

The long ones were phased out around 67.5/68 in favor of short ones that have clear tubing to run them the rest of the way down. The long ones look cool, but are prone to breaking.
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Re: Fuel leak - SU carb, any ideas?

Post by Bwk2000 »

spl310 wrote: Sat Aug 20, 2022 3:40 pm The long ones were phased out around 67.5/68 in favor of short ones that have clear tubing to run them the rest of the way down. The long ones look cool, but are prone to breaking.
Yup. They do look good, which is why I eventually would like to replace mine with full-length ones.
If I remember correctly, there were bracket(s)? attaching the drain tubes somewhere on the oil pan. Seems to me, that rigid mounting point, along with the twisting motion of the engine under acceleration, is likely what kept crimping/breaking these things. Adding a flexible rubber mounting point (similar to an exhaust hanger) should help keep them in one piece. 🤔
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spl310
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Re: Fuel leak - SU carb, any ideas?

Post by spl310 »

Yes, there is a bracket with a specific O ring at the bottom. They look cool, but no one but you will see them.
"Wow, a Roadster!" Stuart Little

1967.5 2000
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Kinnaird
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Re: Fuel leak - SU carb, any ideas?

Post by Kinnaird »

Due to be short on time and in the dark I rigged up a solution since I couldn't get the clear hoses down the engine bay - hoses going into a zip tied Walgreens prescription bottle. Would only work once but that's all I'd need/ possibly even a worse fire hazard but worked out
20220822_203716.jpg
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Re: Fuel leak - SU carb, any ideas?

Post by Gregs672000 »

Works... this way you'll know!
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Re: Fuel leak - SU carb, any ideas?

Post by Kinnaird »

Also that location where the medication bottle is, what is suppose to actually be there?
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Re: Fuel leak - SU carb, any ideas?

Post by Bwk2000 »

The window washer bottle.
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Re: Fuel leak - SU carb, any ideas?

Post by Kinnaird »

Bwk2000 wrote: Fri Aug 26, 2022 9:01 am The window washer bottle.
Thank you, that was probably the clear boxy bottle in the trunk
1968 Datsun 1600