Vacuum hose routing

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DoubleDingo

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Replaced the vacuum hoses on the truck. Some were new but I replaced them anyways.

My question:
On the sticker, does the "nut/bolt" looking part of the EFE TVS and SPARK TVS on the diagram indicate the portion you put a wrench on to tighten them? If so, does it matter how the hoses are routed from the respective TVS's?

I ask because I noticed the hoses I removed were routed 180 out on those. So I routed them according to the "nut/bolt" portion on the sticker. I guess once everything is hot vacuum will flow through the hoses, but I am sure the engineers intended the vacuum signals to flow one way, not any way.

Am I correct on this? Or did I mess up the routing? Basically I routed everything according to the sticker, assuming the nut/bolt symbol of the TVS's indicates where they screw into the intake and thermostat housing.

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DoubleDingo

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Okay, this is what I'm talking about. I added arrows to the image to show you guys can see what I'm talking about.

Assuming where the arrows are pointing, that is the nut/bolt portion of the TVS's, that would be where the wrench is used, correct?

If that is correct, the hoses were hooked up wrong, and the vacuum signals were not as intended. Or, I read the diagram wrong and screwed it up.

Does anyone have a legend that shows what the various symbols mean? Why are some hoses solid color, and others have broken-up color?

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DoubleDingo

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SirRobyn0

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sorry @DoubleDingo I should have seen this post sooner, but have been MIA a lot lately do to personal reasons. I actually really like being pulled back in as it's a good distraction from the bad stuff.

It doesn't matter. They are just switches on or off regardless of top or bottom vacuum source. But like you I always hook them up as the diagram shows, since I figure that's the intended way to have them hooked up.
 

DoubleDingo

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sorry @DoubleDingo I should have seen this post sooner, but have been MIA a lot lately do to personal reasons. I actually really like being pulled back in as it's a good distraction from the bad stuff.

It doesn't matter. They are just switches on or off regardless of top or bottom vacuum source. But like you I always hook them up as the diagram shows, since I figure that's the intended way to have them hooked up.
Cool, thank you. To me, the truck seemed to run better with them hooked up according to the diagram. Maybe placebo effect...lol... I'll leave them as they are, and continue replacing other hoses.
 

Bextreme04

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I agree with everyone else, I would read the diagram the way you stated. I also don't think it would matter, it is just a plunger inside that connects the two passages, shouldn't matter for the two port versions. There ARE some special ones with three or more ports where it does matter. Those ones will usually designate the source connection if applicable on the body in some way. Some will have a single source switching between two outlets depending on temp.
 

DoubleDingo

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Carb'ed Vortec 350; 1972 L48 350

89Suburban

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Okay, this is what I'm talking about. I added arrows to the image to show you guys can see what I'm talking about.

Assuming where the arrows are pointing, that is the nut/bolt portion of the TVS's, that would be where the wrench is used, correct?

If that is correct, the hoses were hooked up wrong, and the vacuum signals were not as intended. Or, I read the diagram wrong and screwed it up.

Does anyone have a legend that shows what the various symbols mean? Why are some hoses solid color, and others have broken-up color?

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Colors are mostly for making the chart easier to visually follow the routing, though some factory hoses may be marked with the corresponding colors via a stripe on the hose. I venture to guess the solid colors are constant vacuum and broken colors are "triggered vacuum" or "off idle" vacuum from above the throttle plates.

KISS. Keep it simple silly, that label is there for a reason. Route the hoses as shown to eliminate any doubts. :)
 

DoubleDingo

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81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
Engine Size
Carb'ed Vortec 350; 1972 L48 350

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