I prefer to stay with what the engineers designed and built unless there is a known defect and the manufacturer comes out with a fix for the specific problem.
Carbs typically have an expected input pressure. I am not experienced with the little ones used on lawn equipment ,but it seems an automotive pump ( are there others?) would probably be too much and likely to knock the inlet valve open permanently . Auto pumps run 3 psi and UP. :2cents:
You will have very little 'pressure' in the fuel line to the carb... but you need some so don't abandon the factory fuel pump, it will give you enough without giving too much.
Have you tried running it with the gas caps off... your tank vent system could be plugged and then will not allow fuel to be pulled from the tanks...
also if the fuel line supplying fuel to the pump is getting Hot, it will vapor lock and not be able to pump... :smile:KennyV
You said that you eliminated the fuel shutoff solinoid. Did it run OK after "that" change? The fuel circuit on some of these machines can be tricky. I tried putting in a "T" in an Exmark Z and it wouldn't work. It's been a while, but it had something to do with the fuel return due to the fuel injection on the Kawai's
"Have you tried running it with the gas caps off... your tank vent system could be plugged and then will not allow fuel to be pulled from the tanks...
also if the fuel line supplying fuel to the pump is getting Hot, it will vapor lock and not be able to pump... :smile:KennyV[/QUOTE]"
Had the same problem with my Husqvarna - loosen the fuel cap - problem solved.