Secondary air flap rubbing

[jbplanck]

My secondaries are opening inconsistently when applying WOT. Sometimes they open, sometimes they do not, sometimes there is a long 3+ seconds WOT) delay. I am suspecting this spot I found the secondary air flap rubbing on the air horn is the culprit. The secondary meter hanger has fresh new plastic cam.

What do you think regarding the rubbing? It is not right to left rubbing. It is front to back rubbing. This carb was just rebuilt using Cliff's book and rebuild kit.

The RUB AREA is right in front of the big black screw in the pictures. See pics and video in links below.

http://1drv.ms/1q5IrtO
http://1drv.ms/Vs3Wvr
http://1drv.ms/1q5IyWe

What you cannot see in these pics is the extra pressure I apply to force the air flap open. You can easily see it get hung up on the way back up.

[77cruiser]

I had one exactly like that. I loosened the screws & adjusted the flaps.

[Cliff Ruggles]

I would also get a sanding roll on a high speed dremel and clearance if/as needed if you can't get them to quit rubbing by moving them around.....Cliff

[jbplanck]

Thanks for the input 77Cruiser and Cliff.

Although loctite was applied to the screws on the air flap butterfly during the rebuild, I was able to back off each screw (1/8 a turn for one,  1/4 for the other). Viola! the rubbing stopped. Now I get WOT with secondaries through all gears as I accelerate. WooHoo!!!!

For future reference on the forum, here is a guy with an aftermarket carb for his 912 Porsche with a similar problem, and his solution.

http://www.912bbs.org/vb/showthread.php?45204-Adventures-in-Dellorto-Tuning/page2