73 Mach 1 351C w/AC vacuum line

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DeereFanatic

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I have this steel double vacuum line I believe comes from the 4 port manifold on the firewall and to the soup can looking reservoir on the inner fender. I can’t figure out how to route it. Does anyone have a picture of one routed?
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Thanks in advance

Dennis

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Thanks Carolina. Looks like your black canister just has a vacuum line on it connected at the firewall.
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The lines I’m talking about is the ones in this pic right under the3/8 vacuum line in the pic. It’s got the 90 degree coming up from the transmission

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That's the trans vacuum line for the dual diaphragm modulator. The clip goes under the upper passenger side bellhousing bolt. The center of the modulator gets full manifold vacuum, the outer area receives vacuum through a temp controlled vacuum switch that also operated the EGR system. I've attached the '73 vacuum diagrams below, you need to figure out which one applies to your car.

Lots of good info in the post by rackerm

https://www.7173mustangs.com/thread-ac-heater-box-vacuum-line-diagram?pid=303517#pid303517

1973_ServiceManual_Vol6_EngineEmissions_Mustang.pdf

 

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Hemi where does that steel line route to? It looks like it’s bent to mount over the transmission but when it gets to the inner fender it don’t come out in a logical position to hook up to the canister.

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The black vacuum reserve canister hooks to direct manifold vacuum via the tree threaded into the rear of the intake, and the feed line going through the firewall for the A/C system. Look at the thread I linked to, it has diagrams.

Pic below is from the 429 Megasite, but shows how the steel line is routed on the transmission.

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Since my car is a 4 speed does not have the metal line you have with automatic. The vacuum canister just is a storage tank so that the vacuum motors on the AC have enough to open and close the doors. Would also give volume for the transmission also. The diagrams should show you what you need.

 
The canister is for the a/c vacuum motors, not the transmission vacuum modulator. The transmission lines connect directly to the manifold tree or the temperature controlled vacuum valve.

 
Me and my buddy figured it out. It goes down to the modulator valve on the transmission.
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Thanks for all the help.

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