How to fix that mangled C spring in your petcock

[WilliamGLX81]

So, you have a vacuum operated petcock with a mangled, twisted bit of metal in the bottom of it.

After about an hour of bending it (it luckily never work-hardened and broke) into a variety of positions, I re-thought the design, and came up with one that works. Here are some photos that should help guide you.

Make sure you bend ONLY the straight part of the ramp(the _ part that deviates from the smooth C_ shape) and not any of the curved circle. Bending behind the transition from linear to curved can make your petcock leak in some positions because it makes the arm that presses on the pin most of the time.













Cheers!

PS If you look at the one in this photo here http://www.thegsresources.com/_forum...d.php?t=211194, the spring is broken just where the ramp/arm meet, where the C straightens out.

[Andrew Vanis]

the next step would be to cut that clip from flat stock and bend it to shape.

[Steve]

Even more important that having the proper shape is to have proper orientation.

If you look on the back of the barrel that pushes against it, you will see a ramp.
THAT is what pushes that center pin toward the plunger in the diaphragm that closes the fuel flow.
If the spring is not correctly positioned in relation to that ramp, you will either not have a PRIme function or you will have an unintended PRIme function.

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[WilliamGLX81]

Back of the barrel? The plastic cone? On mine, that has no ramp, just a single rectangular tab.

[Andrew Vanis]

mine has a rectangular tab as well

[Steve]

I will have to take one apart here to have a look, but there is some mechanism on the back of the cone/barrel/whatever that pushes on the spring when the petcock is turned to PRIme.

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[WilliamGLX81]

I agree there's something there, but on mine, I'm sure it's just a plastic tab with a rectangular face.