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70 LT-1 vacuum line question

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Old Nov 30, 2025 | 03:03 PM
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Default 70 LT-1 vacuum line question

While putting a new cap on my car I noticed an orphan vacuum line buried near the bellhousing. I've attached a couple of pictures. I suspect the PO installed a new line from Intake and didn't T in the small line connected to the part I found. I don't have a vacuum leak the size that this would be. I hope this makes some kind of sense
This what I found laying on the bellhousing it has a white line. the small line is the one I'm trying to identify in the next picture its goes into the cabin
This what I found laying on the bellhousing it has a white line. the small line is the one I'm trying to identify in the next picture its goes into the cabin
I'm wondering what this might go to.
I'm wondering what this might go to.
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Old Nov 30, 2025 | 05:09 PM
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Hello,
Perhaps here?
The small hose goes through a grommet in the fire wall and supplies vacuum to the heater/defroster controller on the console.
Regards...










Last edited by Alan 71; Nov 30, 2025 at 06:06 PM.
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Old Nov 30, 2025 | 05:15 PM
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Alan thank you yes that's what mine looks like am I correct that it T's into the manifold vacuum line?
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Old Nov 30, 2025 | 06:16 PM
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Hello,
On my 71 you can see the large diameter hose is short piece that connects to the 2 small METAL tubes that run across the firewall behind the distributor and below the wiper motor.
Just what you have depends are where the vacuum relay for the wiper door is on your car.
It changed from the firewall near the master brake cylinder in 70 to the rear of the inner fender on the passenger side in 71.
Regards....

In looking at your photos I see where the relay is so look for a large connection for the short piece of hose.

Last edited by Alan 71; Nov 30, 2025 at 06:26 PM.
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