I'd differ here a little, I've been able to test mine on driveway, but you gotta punch the throttle suddenly to WOT, then hold it. If it is working, it will pull the secondary open at least some. You have 2 possible issues to isolate then diagnose. 1. The linkage for the secondary may be sticking, this is easy, Oil, WD 40, carb cleaner, etc.. 2. Your dashpot (vac diaphragm that opens secondary) is not working. #1 you just hold throttle open with car off, see if secondary flops open easy with your thumb on back side of carb & springs back. # 2, pop the circlip off the arm coming from bottom of dashpot where it connects to the secondary shaft/linkage (have another clip for when you drop this one & can't find it, or in a pinch, piece of bailing wire) then let if just hang there. Start the car, rev it up over 4K & see if the dashpot arm moves, if it doesn't, your dashpot is no good, or the little port to it is clogged ( blast carb cleaner down it), or the o ring is not there or leaking/old, or there is a major vac leak. there is a small brass orifice where that o ring is, I can't remember for sure, but there is a specific point to be set it at, like screwed in all the way, or it is supposed to allow for adjustment of some kind. As for the loose hose, if you feel vac on it with your finger, get another of the little caps & pull the hose & cap it.