What does this vacuum line go to ?

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What does this vacuum line go to ?

delco1946
This post was updated on .
 I’m trying to double check the vacuum lines on my engine because somethings wrong. Although in looking at all my resources I have no idea what the vacuum line connecting into the back of my Motorcraft 2140 carburetor is or where it supposed to go to ?  It’s not a part of the EGR and it’s the top most vacuum line at the back .

Also In line with the vacuum are two different colored cylinders -how do they differ?  One is gray and black and the other is teal black and white . I am assuming one is a vacuum delay valve and the other is a vacuum retard delay valve but I don’t know which is which .
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

delco1946
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

delco1946
Argh. Thoroughly frustrated.   Anyone have or know of photographs of what a 1981 351M vacuum line system should look like? That would be so much more helpful than a schematic. My engine seems to be running worse now. Not better.
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

Gary Lewis
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I have some '81 351M vacuum diagrams here: Underhood/Vacuum/Vacuum Systems/Vacuum Diagrams/351M & 400.  Is that one the same as yours?  If so, we can figure it out.  

Are you keeping all the emissions stuff?
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: What does this vacuum line go to ?

LARIAT 85
In reply to this post by delco1946
The hose in your hand is not connected to the right place.

Do you still have the stock air cleaner?

That hose is supposed to be connected to the vacuum motor on the snorkel part of your stock thermostatic air cleaner.  And, the colored check valve is turned backwards.  The teal-colored end should face the snorkel, where it is connected on one end by a short section of vacuum hose.  The cream-colored end should have a longer vacuum hose that connects it to the air cleaner lid.

Remove the hose from the carburetor.  The port on the carburetor it is currently connected to is the fresh air port that is supposed to be used for a "fresh air tube" for the stock thermostatic choke.  It should have a small section of rubber hose connected to it, and then a metal line is connected to the the other end that routes down to a chamber on the passenger-side exhaust manifold.  This chamber should have a second insulated tube - called the "hot air tube" - in it that connects back up to the carburetor, right behind the choke cap.  

If you don't have a thermostatic choke, you should cap that off, as it will let unfiltered air into the filtered side of the air cleaner.





Lucille:  1985 Ford F150 XLT Lariat

*Colors:  Dark Canyon Red exterior, Canyon Red interior
*Engine: 5.0, CompCams 31-230-3, "Thumper" E7 heads, Edelbrock Performer intake, Autolite 4100 carburetor, DuraSpark II ignition, Thorley Tri-Y headers, Flowmaster dual exhaust, H-pipe.
*Drivetrain:  AOD transmission, 3.55 gears, 2wd.



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Re: What does this vacuum line go to ?

delco1946
In reply to this post by Gary Lewis
It’s similar but  I don’t have air-conditioning, I have the thermactor system, and a thermal valve switch Sticking out horizontally out of my thermostat housing, and then a 4 pronged vacuum tree sticking  vertically out of the thermostat housing.  I was tempted to take my EGR valve out to look at it and maybe just replace it assuming that it’s probably that gets old . I had multiple systems including the thermometer connected to my cold weather switch in the air cleaner housing (  I don’t see any evidence that anything should be connected to that except for the snorkel ) . I disconnected everything from that and reconnected the vacuum motor in the snorkel which had been abandoned.
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

delco1946
This post was updated on .
Lariat- the The tubing in my hand was originally connected to the top of my stock air cleaner, however the other connection points within the air temp switch  simply connected to a vacuum tree in the back of the manifold. This means there was nothing connected to my snorkel. Said differently- manifold vacuum was going to the air temp switch and then to the back of the carb via the large diameter tube in question. From other diagrams I’ve looked at intake manifold should connect to the air temperature switch On top of the air cleaner, which should then connect to the side of the air cleaner to the cold weather switch, which should then connect to the snorkel. Correct?

Regarding the thermostatic choke/your second paragraph it’s going over my head currently. So I’m off to the store to get a lot more vacuum line and then I’m going to study up so I can get this right!

Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

delco1946
Here’s some new pictures after I reassembled everything just to test it. So this isn’t how I am planning on leaving it, but I only messed with things that I felt more comfortable with which is why you see weird tubing on the air cleaner. One line of the tee on the air cleaner now goes to the CWS  which I am pretty darn sure is correct, and the other goes to the tubing I originally held in my hand in that first picture as that is what it was connected to originally and I know at least at that point in time my truck ran so I left it.   In my hand below is The other change I made which was in splicing the thermactor air bypass. Per The radiator label, after the temperature valve switch on my the thermostat,  vacuum goes to both the EGR and the thermactor. It first passes a vrdv enroute to the thermactor (Which I assumed was the teal thing) and ( via tee in my hand) separately passes a vdv enroute to the egr,  (which I assumed was the gray and black thing).

 
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

LARIAT 85
I don't think the way you have it is correct.  That looks way too complicated.

Look at the connections on the air cleaner in the video below:
https://www.youtube.com/watch?v=VyJ7ybQBMuc

I think the temperature switches on the side of the air cleaner are for emissions devices.  Can you post a picture of your vacuum diagram under the hood?


Lucille:  1985 Ford F150 XLT Lariat

*Colors:  Dark Canyon Red exterior, Canyon Red interior
*Engine: 5.0, CompCams 31-230-3, "Thumper" E7 heads, Edelbrock Performer intake, Autolite 4100 carburetor, DuraSpark II ignition, Thorley Tri-Y headers, Flowmaster dual exhaust, H-pipe.
*Drivetrain:  AOD transmission, 3.55 gears, 2wd.



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Re: What does this vacuum line go to ?

delco1946
This post was updated on .
 So what I have set up is quite similar to the YouTube video. Only with the cold weather switch, that appears to take the place of that blue cylinder thingy in the video. I followed the cold weather switch document on this website, which also aligns with my Haynes manual (or at least I’m pretty sure I did ).  My understanding is that the CWS basically holds a vacuum below 55° so that if you accelerate it the cold, the vacuum motor stays open.

*Edit * maybe I’ll just switch to you design Lariat- the cws stuff doesn’t show on my label so perhaps I’m getting carried away.


The only reason I stuck a temporary tee on the air cleaner is that I don’t know where that tube in the first pic goes to. That unknown tube is I. The first pic, and its not coming out of the manifold, which I think would indeed go to the snorkel via air temp switch and cws, rather it’s coming from the back of the carburetor.
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

delco1946


Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

Gary Lewis
Administrator
To make it easier to read:

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: What does this vacuum line go to ?

delco1946
.
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

FuzzFace2
delco1946 wrote
.
Remove that hose off the back of the carb that has the teal / black / white valve in it.
See that other short hose on that metal line just under it? One end goes into the intake manifold the other end with the short hose goes to the carb you pulled the other hose from.

Now that hose you pulled off with that teal / black / white valve (VRDV) in it based on the vacuum line sticky should go to intake manifold vacuum supply then to the A/CL BI-MET switch on the filter lid or the side of the housing (don't know what one?) then to the filter housing snorkel door A/CL DV.
Dave ----
Dave G.
81 F100 flare side 300 six / AA OD / NP435 / 2.75 gear
http://cars.grantskingdom1.com/index.php/1980-Ford-F100?page=1
81 F100 style side 300 six/SROD parts truck -RIP
http://cars.grantskingdom1.com/index.php/1981-Ford-F100
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Re: What does this vacuum line go to ?

delco1946
Hot damn! Thank you!! It’s coming together. Now what is the black and grey valve and which way should it orient?
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

FuzzFace2
delco1946 wrote
Hot damn! Thank you!! It’s coming together. Now what is the black and grey valve and which way should it orient?
By the vacuum sticky it looks to be the VDV going to the air bypass valve?
It also looks like the white part of all the valves should be to the vacuum supply, look at the sticky Gary posted on the right side.

The only thing I am not sure on is the 2 temp switches, 1 in the lid & the other on the side of the housing and what each is called so you know what one gets used for what.
Dave ----
Dave G.
81 F100 flare side 300 six / AA OD / NP435 / 2.75 gear
http://cars.grantskingdom1.com/index.php/1980-Ford-F100?page=1
81 F100 style side 300 six/SROD parts truck -RIP
http://cars.grantskingdom1.com/index.php/1981-Ford-F100
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Re: What does this vacuum line go to ?

delco1946
In reply to this post by delco1946
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

delco1946
This post was updated on .
Not perfect but I’m close. I’m unsure as to how the vacuum is affected by the temp switches at the thermostat housing. Im getting no/weak vacuum with a warming engine if I put my fingers over either tube connecting to the side of the air cleaner ( which Coincidentally is labeled TVS on the inside matching with the schematic).   There appears to be two temperature switches in the circuit  With the thermactor and egr. How do they interact?


It’s idling very rough- almost stalled twice,  so much so I actually had to feather the gas for a while before would stay on. Thoughts? Could this now be due to a bad egr?
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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Re: What does this vacuum line go to ?

Gary Lewis
Administrator
How the air cleaner works is shown here: Fuel Systems/Air Cleaners.

And an EGR valve that is not closed can certainly cause problems with the engine idling.  And the EGR valve can be open due to getting vacuum when it shouldn't or because there's carbon in it keeping it from closing.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: What does this vacuum line go to ?

delco1946
This post was updated on .


 I’ve given up for tonight, and I simply disconnected the EGR valve in which fixed the rough idle issue suggesting its a plumbing issue and not an egr issue.
Christopher in Portland Or. 1981 F250 Ranger XLT 4x4 trailer special 351M, and auto C6
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