I had same problem with my 29.5
I had the same problem with my 1995 29.5 hull # 175. What I finally discovered, after several dangerous situations caused by this problem including being stranded on rocks was a design defect that resulted in a constricted fuel flow and delivery top the engine. After trying everything that everyone recommended, I decided to completely clean out and inspect the entire fuel system from beginning to end. This seemed pretty drastic for an almost brand new boat but I was desperate. I drained all the fuel from the tank using a small pump, and then removed the bulkhead panels in the aft portion of the aft berth and proceeded to remove the fuel tank. This was amazingly easy. Hunter did a great job at designing this part of the boat. Just disconect the fuel lines and fittings, cut the hold down strapping material, and the tank will slide right out of the space it is in. I then removed the pick up tube from the tank and discovered the problem. A screen had been installed on the bottom of the pick up tube. it was installed so that it was folded over the bottom of the pick up tube opening and had been soldered or glued together. The result was that the tube was almost completely closed. Since this engine uses very small amounts of fuel, it ran fine at slow speeds. I also discovered plastic "sawdust" in the tank from the drilling operations to install the fittings. Evidently, when the engine was revved up, suction increased and a very small amount of this plastic plugged the remaining small openings in the screen thus choking off the fuel. When teh engine used all teh fuel in the system it could, it stalled. After a few minutes, with the suction released, the holes opened, and the engine would run fine again, until the cycle repeated. After consulting with some mechanics, I decided to remove the screen completely - after all that is why there are both primary and secondary filters built into the system! Plus, any continued future problems could then be dealt with at the primary filter which would not require removing the tank. I replaced the tank, added new strapping and connected the lines. I have never had any problem at all with theis system in the last 4 years. Good luck with your repair. i would be curious to know what you eventually find. Bill Murray
