Black particles particles keep getting into the carb's float bowl in my '74 X1/9. The carb is the stock Weber 32 DMTRA 200. Particles didn't used to get in, but after a carb overhaul by a now defunct Fiat shop, black particles get into the float bowl which plug the jets. I have replaced the mechanical fuel pump with a New-Old-Stock fuel pump and I have replaced the fuel filter and the fuel hoses. But these small particles get into the float bowl and they're lifted by the sloshing when I turn left over a bump (such as into or out of a driveway) and one will be sucked up to a jet hole if the fuel flow is for more than an idle. Sometimes I can force it through with high revs, sometimes I have to stop and turn off the engine and pound on the air filter to dislodge the particle so it drops back to the bottom of the float bowl. Until the jet is cleared, the engine has only idle torqe at best, and it usually dies if I don't pump on the accelerator. I've replaced the transparent fuel filter twice, and although the filter element may look darkened, there are no particles lying at the bottom, and disassembly shows no gaps for dirt to pass through. I've examined all the vacuum hoses connected to the carb, and they're all tight or purposefully blocked off. But somehow, small particles get into the float bowl - as if the fuel hose between the fuel filter and the carb were slowly disintegrating. (I use Chevron gas.) I've checked the crankcase breather hose that leads to the interior of the air filter, and it's tight at both ends, and I've checked and replaced the air filter twice. Has anyone else had this problem? Was there a solution? Vido P.