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Vacuum Break Diaphram?



Hi everyone,

What does the vacuum break diaphram do? (I also think it is called the choke pull-off valve). I'm talking about the part right above the choke coil on a stock Qjet. (passenger side)

I've had a hard time getting mine to run below 1200 RPM, and I just determined that this part was bad. (It would not hold a vacuum at all). So I replaced it tonight, along with a new Vacuum Advance Unit.

I didn't get a chance tonight to see if the new parts helped (Because... of course... the battery was dead...), but I was wondering what exactly the vacuum break does. It looks like it just connects to the side of the secondaries and pumps back and forth...

Thank you,



vaccume brake

if i remember correctly, when you get on it and the choke is on, this will allow the choke to pull off and away you go. i may be wrong. but then again, i may be right.



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