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Vacuum Hoses Help

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Old Mar 26, 2017 | 12:52 PM
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Default Vacuum Hoses Help

Another PO at some point cut a bunch of vacuum hoses on my '78 SA. I figured out after searching through here on random missing vacuum lines last night that the EGR vacuum hoses and whatnot were pulled and the nubs broken off the EGR TVS switch, so I'll fix those at some point.

Found these larger ones cut by the drivers side under the master cylinder. 3 hoses and come off a canister (I think only 2 of them do and then "t" early on. I want to buy the right hoses to fix whatever these go to (I'm sure I'm prob. opening another can of worms as this person sliced these off for some reason). Then find where these are supposed to plug into on the other end.

Why would they do that? Same goes for the EGR hoses. Was there likely some larger problem and the easiest fix was just chopping them off? UGHHH.
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Last edited by raydog9379; Mar 26, 2017 at 12:54 PM.
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Old Mar 26, 2017 | 02:06 PM
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Looks like maybe you're missing the vapor canister.
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Old Mar 26, 2017 | 02:24 PM
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This how the top of the canister should look if you have one:



and the hose destinations:

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Old Mar 26, 2017 | 08:50 PM
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There's a canister way under there.... Some lines are actually connected after digging way in there (like the fuel tank one). I must have a big head as it's hard to get in there and see, but I can kinda get in there.

I bet these other ones would eventually route to the missing ones for the TVS and whatnot on the other side of the engine bay. So someone just disconnected all the smog setup I suppose. Why would they do that? Is there some advantage or was it more that something else broke down the line and this was an easier fix to just start butchering stuff?
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Old Mar 27, 2017 | 04:44 AM
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Originally Posted by raydog9379
There's a canister way under there.... Some lines are actually connected after digging way in there (like the fuel tank one). I must have a big head as it's hard to get in there and see, but I can kinda get in there.

I bet these other ones would eventually route to the missing ones for the TVS and whatnot on the other side of the engine bay. So someone just disconnected all the smog setup I suppose. Why would they do that? Is there some advantage or was it more that something else broke down the line and this was an easier fix to just start butchering stuff?
Some owners believe emission control devices are huge power drains but little do they realize those devices operate off vacuum so when they cut and run, open vacuum robs your engine of power. duh!

Buy a replacement hose vacuum kit that will have hoses pre-cut with the proper diameter. Search on the forum here for L82 hose schematics. It should lead you to the Wilcox hose schematic for 78. It will show the proper routing and terminal point for those hoses. Finally, The TVS switches are hard to repair once those nipples are broken off but do a google search and you should find service replacements. someone on the forum went through this a few months back...see if you can find their discussion thread.

hope this helps!
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Old Mar 27, 2017 | 09:50 AM
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Originally Posted by hunt4cleanair
Some owners believe emission control devices are huge power drains but little do they realize those devices operate off vacuum so when they cut and run, open vacuum robs your engine of power. duh!

Buy a replacement hose vacuum kit that will have hoses pre-cut with the proper diameter. Search on the forum here for L82 hose schematics. It should lead you to the Wilcox hose schematic for 78. It will show the proper routing and terminal point for those hoses. Finally, The TVS switches are hard to repair once those nipples are broken off but do a google search and you should find service replacements. someone on the forum went through this a few months back...see if you can find their discussion thread.

hope this helps!
Thanks! I'll get these all fixed and circle back if I need help.
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