I have a 750 vac, there is usually a vacume port in the primary jet plate above the idle screw, there is just a hole in mine, when i give it gas it sucks air, Is it supposed to be like that, i wouldnt think so but maybe so lol. it doesnt look like anything is broke off so i dont know.

Sounds like the metal tube for attaching a hose is broken or missing.

Should be easy enough to fix--I bet you can buy a short length of brake tubing the proper size. Cut to length, bead the end if you can, then pop it into the metering block after removing any remnant of the old tube.

would the vacume leak cause problems, i have had a heck of a time tuning it, but it ran decent.

somewhat, it is ported so it wont effect your idle but id get it fixed