1-1/4" SU carb conundrum

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Peter Laidler
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1-1/4" SU carb conundrum

Post by Peter Laidler »

Just been overhauling a set of reasonable good-but-used 1.25" Cooper SU Carbs for clever Trevor and noticed when centring the jets that the brass part of ONE of the jets - AUD 9141/2 was .2" SHORTER than the other, At 1.2" as opposed to the norm of 1.4" .

Never seen it before....., or even heard of it! Only noticed it because it fell .2" BELOW the internal bridge of the carb body.

Strangely, while the other carb had the standard GY needle, the duff-jet side was fitted with a GX needle.

Any out there got any ideas? Ever seen such a short jet? Ever heard of such a thing? Anyone need one?
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Peter Laidler
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Re: 1-1/4" SU carb conundrum

Post by Peter Laidler »

No takers......, any ideas anyone....
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Re: 1-1/4" SU carb conundrum

Post by AndyPen »

Nee one on me Peter- always fitted everything in pairs?
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Re: 1-1/4" SU carb conundrum

Post by Peter Laidler »

Yup....., they came OUT as a pair but no one noticed that one was slightly shorter. I bet that side was running rich!

A bit like the different L and R fuel bowl tops that nobody seemed to notice. Anyway, another thing to put down to experience. There we go.....
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