# Secondary vacuum question.



## RMTZ67 (Mar 12, 2011)

Curious if the secondary vacuum dohicky is supposed to hold vacuum or not. I got a new float and high flow needle and seat from cliff, and while putting the Qjet back together I sucked on the hose to the secondary vacuum canister and put my tongue on it to seal it and it did not hold. Is this normal?


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## PontiacJim (Dec 29, 2012)

Nope. But then again, how good are you at sucking? I'd like to get a pic of that, please. 

It should hold vacuum - assuming you are talking about the vacuum diaphragm on the side of the carb? A Q-jet? You may have a cracked/split case? I'd use a hand vacuum pump which would be more accurate.


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## RMTZ67 (Mar 12, 2011)

Ya I think I will rent the pump this weekend. It takes a lot of effort and not as satisfying as that other tool we use to use back in the day. I think it was called a bong or something like that  lol.


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## integrity6987 (May 10, 2017)

Vac pumps used for brake bleeding are good tool and have more utility than brake bleeding (this is an example) They are less than $20 at Harbor Freight.


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## PontiacJim (Dec 29, 2012)

RMTZ67 said:


> Ya I think I will rent the pump this weekend. It takes a lot of effort and not as satisfying as that other tool we use to use back in the day. I think it was called a bong or something like that  lol.


Ya, or its opposite, the power hitter, as my buddies used to use.


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## BearGFR (Aug 25, 2008)

It should hold a vacuum, but if it you can 'operate' it by sucking on it then whatever leak there may be is of very little consequence. Why? Because in operation with your engine running, there is manifold vacuum present all the time - except at wide open throttle/heavy load - which is when it's supposed to open. Unless it's leaking enough to create a lean condition, don't sweat it. 
As others have mentioned, a more valid way to test it would be to use one of these:
Brake Bleeder and Vacuum Pump Kit

Bear


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