DT5 run problem

[tophat]

I have a DT5 which starts easily,idles nicely and goes great up to 3/4 throttle,then when I try to open up to full throttle it just die's and stops. I have replaced the tank fuel line and bulb thinking that could be the problem but to no avail. Have also cleaned the inline filter on hose leading to the fuel pump. I have had the motor in the garage for a few years and only started it a couple of times a year. Any ideas on how to fix the problem? Thanks.

[boats.net]

Probably need to remove and clean carb, probably varnished up from old gas if been sitting that long.