It sounds like you're on the right track and something is gummed up in your carb. The rebuild kits were around $20 if I remember right, so that might be an avenue you would want to consider if you don't want to pony up for a new carb just yet.
Might also be a pump problem if the motor in it is getting flakey but that's going out on a limb. A filter problem would be more constant.
Let us know if anything changes for the worse.
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1976 2x4 LUV: 4-speed, 32/36 Weber, desmogged, 3.42 gears
My '76 LUV and Impulse 5-speed for sale:
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