Heater Hoses, routing

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andy72

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[url=https://ibb.co/R9rNbJs][img]https://i.ibb.co/376vdPj/DSC06636.jpg[/img][/url]
My car is 351C 72 with air.

When I got the car all the heater hoses were straight hose like on my early mustangs.

Now I find out there is an "S" hose on the inboard heater core fitting and the water shut off valve goes on this hose.

Then I find out there is an "L" hose to connect to the water pump fitting.

NPD only shows the "L" hose in the part number for W/AC, without AC is all straight hose. What's up with that?

What is correct?

Is there any added benefit  to paying for the "S" and "L" hoses, or do most guys just use straight hose?

Just an originality thing to use them, yellow stripes and all? $50 for "L" yellow stripe hoses...

Side note, if you put "heater hose routing" into the search on this website, you get 6 results about the subject that contradict each other as to which fitting

on the heater core goes to which fitting on the block and water pump.

Thanks for any info

 

Hemikiller

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This should help you out. PDF attached of the complete page. I'd say yes on the "S" hose, "L" hose is your discretion.



71 heater.pdf

 

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rackerm

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Stock 1973 Mustang Convertible with a 351C 2v and C6
Modified 1970 Mach 1 M-Code with a 351C 4v Manual

My car is 351C 72 with air.

When I got the car all the heater hoses were straight hose like on my early mustangs.

Now I find out there is an "S" hose on the inboard heater core fitting and the water shut off valve goes on this hose.

Then I find out there is an "L" hose to connect to the water pump fitting.

NPD only shows the "L" hose in the part number for W/AC, without AC is all straight hose. What's up with that?

What is correct?

Is there any added benefit  to paying for the "S" and "L" hoses, or do most guys just use straight hose?

Just an originality thing to use them, yellow stripes and all? $50 for "L" yellow stripe hoses...

Side note, if you put "heater hose routing" into the search on this website, you get 6 results about the subject that contradict each other as to which fitting

on the heater core goes to which fitting on the block and water pump.

Thanks for any info
I don't have a picture that clearly shows the routing. You can see the 90-degree hose on the inside left bends over the valve cover and alternator in this picture. I suspect you could just use a straight hose instead. The "S-hose" has the heater control valve on it and is the inlet (supply) that connects to the bottom heater core tube. This means the heater-outlet hose is routed from the top heater core tube to the water pump inlet. I read that this helps with the removal of air bubbles from the heater core. I made my own "S" hose from the extra yellow strip hose I had. I gradually shaped it into an S and applied heat in the oven and let it cool. I repeated this a few time until I had the enough of an "S" shape and it stayed that way. 









This is for a 1970 mustang 351C 4v with A/C, but it is the same with the exception the 70 used a metal 90-degree tube instead of 90-degree hose on the water supply side.

 
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My original 73 was between the shock tower and the valve cover. Here is pic I just took the factory hoses off couple weeks ago had factory clamps also. The repo hose is nothing like original I ordered radiator and heater neither look like original. Made by Marti also from NPD.











 

andy72

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[url=https://ibb.co/R9rNbJs][img]https://i.ibb.co/376vdPj/DSC06636.jpg[/img][/url]
Guys, Thanks for the input.

Hemikiller, I wondered about the S.  As you can see when I got the car, (before, and current photos)

the previous owner moved the valve to the side, I didn't know about the S hose.

Notice the schematics really don't highlight an "L" hose.  They have the same part #.

Rackerm, interesting how you "made" one...

This is where I'm at on my project now as you can see in the pic. Time to do heater hoses...

DSC05728.JPG

20190320_170705.jpg

 

B229218

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Socal
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71 mach 1 521 c.j.

Guys, Thanks for the input.

Hemikiller, I wondered about the S.  As you can see when I got the car, (before, and current photos)

the previous owner moved the valve to the side, I didn't know about the S hose.

Notice the schematics really don't highlight an "L" hose.  They have the same part #.

Rackerm, interesting how you "made" one...

This is where I'm at on my project now as you can see in the pic. Time to do heater hoses...
Wow, what a beautiful detailing job u did. So thats what my 71 used to look like so many years ago before my dad gave it to me lollerz   

Carolina mustang is right, once we (I) go from stock ,it just becomes just another rest-mod. I am too far down the rabbit whole at this point!!

 

Spike Morelli

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Andy, 

Diggin the before and after shots. I especially zeroed in on the bolt in the float bowl sight window, and the aftermarket brake vacuum system can , used for heater a/c control storage. Restoring a car can be like an archiological ( sp?) dig. You can look at it and imagine it's past.

 
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