AQ130 STARVES FOR FUEL AFTER 5 MIN OF RUNNING

I have an AQ130/270 (1974&

I have an AQ130/270 (1974)that starves for fuel within 5 minutes when running WOT. I tried three different fuel pumps and rebuilt the carbs. Any ideas??? Could it be the float height?? Thanks

"Check the anti-syphon valve i

"Check the anti-syphon valve in your fuel tank. If totally or partly stuck, it will create symptoms like the ones you describe. Also check for any potential source of air ingress or any obstruction/restriction in the fuel suction line."

I have replaced all fuel lines

I have replaced all fuel lines and installed new poly tanks. I even bybassed the filter to eliminate any restrictions. The problem only happens at WOT. Other than that it runs great. I have plans on a long block to ensure engine life as this is a complete restore project that is nearing an end. Paint and new covers are all that is left. I just want to figure this last mechanical issue out with the motor. Thanks.

"As a last test, you can try t

"As a last test, you can try to supply gas to the engine from a gas jerrycan instead of from your boat tank. If the problem clears, then you know where to look next (and same if it does not!!). "

"Try to T in a fuel pump on th

"Try to T in a fuel pump on the output side of your fuel pump then start your engine and run it to failure. If the fuel pressure drops you know the problem is prior to that point if it doesn’t you know it is downstream of that point. If the pressure drops you could check if the new tank is properly vented. If it is not vented properly, it will develop a vacuum when you draw fuel from it and make it difficult to draw more fuel. You could check the cam that manipulates mechanical fuel pumps and make sure it is making the pump actuate properly. You may check your fuel line on the feed side of the pump to make sure it is not kinked somewhere or thin walled enough to collapse under a vacuum. If you have an electrical fuel pump, sometimes they have a regulator that maintains proper fuel pressure. Some regulators have a feedback loop that unloads excess fuel to help maintain proper pressure. If your regulator is sticking open then the feedback loop will unload much of your fuel pressure and the engine may starve for fuel. Finally, I have seen a check valve installed in the fitting connecting the fuel line to the gas tank. This check valve may have a problem moving properly if it has junk in it or if it has not been used in a while. In fact, if I were you I would pull it out and take it to blow some compressed air through it and the whole fuel line for that matter. Make sure you have no obstructions."

Correction... Try to T in a fu

Correction... Try to T in a fuel "Gage" on the output side...

Could always try an electronic

Could always try an electronic fuel injection system.

I had this problem once but a carb rebuild cured it. (AQ131)

"Had this same problem last ye

"Had this same problem last year. I'm assuming you have 44PA1 carbs, if you have rebuilt them try comparing the sizes of the old float valves with the new ones. They could be longer which was the case with mine. Replacing them back with the old ones (after cleaning) did the trick - Hope this helps"