97 challenger no high speed with out blocking return lines

[m2156]

I have a 97 challenger with a 787 in it. This will start and run at low end all day long but falls on its face when you try to hit the throttle. i have rebuilt the carbs and still no change. if you clamp off the return fuel line it will go ball out, what am i missing?

 

[curtcritt]

I have the same boat and problem and haven't tried this yet. Runs fine to about 3500 rpm and then nothing. I've been racking my brain for over a month, tried everything I could think of, and just pulled the boat from the water to rebuild the carbs. Did you figure out a solution or is it still a mystery?

After some more reading I have learned that there's a a 0.8mm restrictor built into the return line outlet at both carbs. I don't think this is a removable component though. The fuel should divide through the restrictor and the fuel filter inside the carb. By pinching off the return you are diverting more fluid through the Internal filters.

I have seen elsewhere on the forums that the original '97 fuel hose is incompatible with ethanol and the hose disintegrates and clogs these filters. Did you clean or replace them when you did the carb rebuild?

C

 

[m2156]

one of the carbs is new from factory, jets swapped the other was completely rebuilt filters and all. not sure if just blocking the return line will hurt anything, there doesnt seem to be any fuel coming back to the tank thru it.