I have a 77 V20 with an 88 rude 150. I've recently had some carb work done to clean out all the ports. Engine idles fine, but when I throttle up, it wants to die out.

After it warms up and crawls along for a while at approx 1200 RPMs, it will sometimes break through and run at top speed. Once I back off the throttle, it goes back to wanting to die out when pushed.

Any ideas? What should I check? Fuel Filter?