Zenith TIN 40 accelerator pump jet leakage

[Einar Irgens]

Hi,

I resently discovered that four of the idle jets let fuel through at idle. I reckoned this could be due to low quality aftermarked needle valves, so I replaced all of them with originals from a spare set of carburetors I have on my shelf. In the process I also adjusted the float level. Result: Fuel still seeps out through the jets, and the engine has startet to hesitate at load. There is also some additional popping in the inlet.

What could cause this leakage if not the needle valves? The fuel pressure is correct.

Additional question: Are the accelerator jets supposed and designed to supply additional fuel at high revs?