Having major problems with my webber fed 12A. Leaning out at high RPM. I assumed it would be fuel pump, so replaced that with a carter pump able to handle up to 15psi... currently running a reg a 6 psi. Now there is another problem with this, and that is that i can not get the pump to maintain a constant psi and will not reach over 6 psi. There are no leaks from reg or pump... so i have no idea!!!!

 

weber carbs work best between 2.5-3.5 psi...4 max. the fuel pump is more than likely not the issue, its more likely jetting related ie). too small main jet , too big air corrector, wrong emulsion tube...many possabilities

 

ok... yeah well it is running 13b jets. Had been advised it would be better off running it too fuely then not enough. so i might change them back to 12a jets and see how it goes. cheers