vacuum secondary issue

[randeez]

main issue: vac secondaries stay open after WOT and letting off.
bg speed demon 650

haven't been driving my truck to much the past few months, after a short wot run the secondaries dont close all the way-sometimes it's open a little, idle will hang around 1400rpm and sometimes it'll stick open enough to let the engine hold 4k+rpm in neutral. so it's not getting caught in one spot.
i've rebuilt the pod with a new vac shaft, o-ring in the pod cover, cleaned out the passages to the pod, doesn't matter what spring is in it. it somehow kicked the primary to secondary link bar out at some point and i thought that was what was causing the problem, but i have bent up another one smoothed out the surface doesn't bind up anywhere as much as i can tell. the only other thing i notice is that the secondary shaft has a little bit of end play in it, not a lot but enough to notice.i've also cleaned/lubed/cleaned again lubed again the shaft and got it nice and free it wasn't rough or anything to begin with but i'm kinda trying everything

anyway anyone every come across this and got any thing i could try out?

[wrightjr]

Not sure man check the carb body/mounting flange for vacuum leaks. Has anybody adjusted the secondary butterflys? Never had a bg carb, but holleys have an adjustment scew on the bottom side of the base plate, maybe somebody opened it up too far. Check your rear float levels if they're too high they can dribble fuel and cause simular problems. What dist are you using? I had simular problems with an vac adv hei. Fixed mine by adding a few more degrees of initial timing and re curving my advance(1 lite/1 med spring).Good luck man.

[Justin_Inc]

baseplate is worn out, pretty common on older carbs. Check the secondary throttle shaft (you'll have to remove carb) wiggle side to side and see if there is any vertical play as well.

[randeez]

i wish i would have realized how cheap an assembled baseplate was i wouldnt have f'd around with this one this long. i got a few other things with the carb this will solve also thanks justin!