My Maverick hasn't been running well for a couple weeks and after taking off the air filter to try adjusting the carb this afternoon I think we found out why. (see attached image) The one circled in green attaches to a hose on the air filter housing. The one circled in red had some rubber around it that was sheared off where the metal ends (it got pulled off before we took the picture). Anyways, the problem is we can't tell if the piece of rubber was just part of a nub to seal off the hole, or if it was part of a hose that is supposed to hook up someplace else. There's no hose flapping around that we can see, but I figure it would be good to ask and see if anybody else could tell us for sure. It's a '76 250 straight 6, and as far as I know everything's stock. Also no ac or anything like that. If you know the answer, thanks in advance!
I looked around for a vacuum reservoir can, but there didn't seem to be one. I just capped it, and now it's running perfectly. Thanks for the responses though!
