So yesterday I replaced my vacuum advance on my 71 F100 390 since the old one no longer was working. After finally getting the retaining clip back on, I pulled the plug off the carb. and replace the vacuum line. When I started the truck, the idle was off, and I could hear air blowing/sucking from the engine. I checked and the *** behind the vacuum line on the carb is sucking air, which it did not before. Any ideas as to why and what I need to do to fix it?

Thanks,
James

 

the clip might be broken and you can't see it? all so look for bad hose or crack in it? hope it helps william

 

Well, I now feel like an idiot.... The vacuum leak from the carb is from the power booster port. I dont know how it was plugged before, or at all, but I dont have power brakes, so i must have lost the plug for it. Thanks for the help!

 

Well just remove the power bootser T port and put just a pipe plug in it.. ez fix
orich