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I'm planning on making my own 5/8" OD heater tubes out of stainless steel to replace the ones in the center tunnel and I am hope someone can provide some measurements or dimensional drawings. Otherwise, I may have to buy/borrow the one in this picture to copy.

I plan to add a 90 bend where both tubes exit into the engine bay so I won't need special heater hoses with a molded 90 at one end. I also plan to expand the tubes at the heater core end to match up to the pipe connections to the core so I won't need special 5/8" ID to 3/4" ID hoses there.

Here's hoping Smiler

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the original Ford outlet from the block (supplying hot coolant to the heater) was 5/8 inch OD tubing or ID hose, the return from the heater was 3/4 inch OD tubing or ID hose. No guarantee that's what De Tomaso used, but since you're engineering these parts from scratch, this is the opportunity to make the parts match each other.

However, I'd like to offer my 2 cents about a safer way.

The hot coolant supply could come from the block, 3/8 inch OD tubing or ID hose, the little heater in the Pantera surely doesn't need a larger supply than that. It could run beneath the car along side the radiator tubes, through the bulk head near the gas pedal and into the heater. No rubber hose within the interior, just copper tubing and flared fittings. Relocate the control valve outside the interior which will require a longer control cable and reducer hoses because its designed for larger diameter hoses.

The return line could use 1/2 inch copper tubing and flared fittings within the interior. Once outside the interior, the heater return plumbing could run under the car back to the coolant pump, or it could dump into the 1-3/8 diameter radiator return tubing near the point where the heater tube exits the interior. That would require a little welding on the radiator return plumbing for a hose connection at that point.

I had a terrible experience happen to me when an interior hose near the gas pedle burst while I was driving 6018. That has left me conviced that rubber hoses within the interior is un-safe engineering.

I'm not adament about this, I mention it simply to kindle thought.
quote:
Originally posted by George P:
the original Ford outlet from the block (supplying hot coolant to the heater) was 5/8 inch OD tubing or ID hose, the return from the heater was 3/4 inch OD tubing or ID hose. No guarantee that's what De Tomaso used, but since you're engineering these parts from scratch, this is the opportunity to make the parts match each other.

However, I'd like to offer my 2 cents about a safer way.

The hot coolant supply could come from the block, 3/8 inch OD tubing or ID hose, the little heater in the Pantera surely doesn't need a larger supply than that. It could run beneath the car along side the radiator tubes, through the bulk head near the gas pedal and into the heater. No rubber hose within the interior, just copper tubing and flared fittings. Relocate the control valve outside the interior which will require a longer control cable and reducer hoses because its designed for larger diameter hoses.

The return line could use 1/2 inch copper tubing and flared fittings within the interior. Once outside the interior, the heater return plumbing could run under the car back to the coolant pump, or it could dump into the 1-3/8 diameter radiator return tubing near the point where the heater tube exits the interior. That would require a little welding on the radiator return plumbing for a hose connection at that point.

I had a terrible experience happen to me when an interior hose near the gas pedle burst while I was driving 6018. That has left me conviced that rubber hoses within the interior is un-safe engineering.

I'm not adament about this, I mention it simply to kindle thought.


George, I know. Getting a hot foot from my car was no fun either.

I do like the idea of having the supply line a little smaller and going underneath the car. Having the return line dumping into the 1-3/8" return coolant tube is also a good idea. Since there is a big cavity under the front boot (unless you relocated your battery there, you could actually move the heater valve in the cavity and possibly use the same control cable. I would prefer to use stainless tubes though just because Smiler

The great thing about doing it this way is that removing the engine is not required to install.

I am still still planning on making pipes out of stainless to replace the rusting steel ones since I've already bought two 6 ft x 5/8" OD seamless stainless steel tubes from Granger. But your idea, George, has given me food for thought. So if you see an add for custom heater tubes for a Pantera, you'll know which direction I went.

Note** the picture is not of my car. See the large cavity?

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quote:
Originally posted by Simon:
Note** the picture is not of my car. See the large cavity?


That small pipe besides the bigger pipes on the picture is the vacuum line .
not for the heater .

Simon[/QUOTE]

I know. I was just showing the area where the heater line(s) could run under the car. It would have to run next to the vacuum line.
My heater tubes were a little corroded at each end so I took them out and replaced them with a pair of strong rubber tubes.

the engine was in situ and to remove the steel tubes its a bit long winded breaking off the bracket spot welds that secure it in the tunnel. By hand not drilling.

then pulling out each tube rearwards slicing it off and repeating the process until they are no more.
What wall thickness did you buy? I have an original set of the aircraft tools to put the beads on the ends of the tubing. That is if the walls are thin enough. Bring them over when you're ready and we can try. I used a company in the Bay Area to make my brake booster vacuum line under the car out of stainless. They were able to put a 90° bend on it per my design and bead the ends. That's another option if you need to have them bent.

Steve
quote:
Originally posted by T.Solo:
What wall thickness did you buy? I have an original set of the aircraft tools to put the beads on the ends of the tubing. That is if the walls are thin enough. Bring them over when you're ready and we can try. I used a company in the Bay Area to make my brake booster vacuum line under the car out of stainless. They were able to put a 90° bend on it per my design and bead the ends. That's another option if you need to have them bent.

Steve


Hi Steve,

Thanks for the offer.

The walls are .035".

I have a set of aircraft beading tools from Parker Appliance Company. Great tool but very rarely used. I also have a vice-mounted Imperial 600-F Worm Gear Tube Bender that's also rarely used that I can't wait to try on stainless. They both had easy lives being used on aluminum and copper tubes. They should be fine on this stainless stuff since its thin-walled.

No one has posted dimensions though for the factory tubes so I'm going to have to buy/borrow the original factory tubes that came out is his car the next time I see him.

Bayani
Last edited by liv1s
Hey Steve,

I also have another beading tool that is table mounted but only works well when used prior to bending. It's kind of useless when the tube has compound bends or when you want to put a new bead on a tube that's already mounted on a car. The Parker is handy for beading tubes on the car.

When I get the measurement/bend angles, I'll make sure I send you the info.

BTW, if you have Instagram, I posted some pictures and videos of your car at the Shriner's Hospital event. https://instagram.com/p/BcRbpOflVER/
There is a lot of discussion on heater hoses and routing in a thread titled "Erica needs to get hosed". It is worth reading.
I don't have any concern using high quality name brand hoses. They have an extremely small risk of failure and that occurs only after they have been in use for decades.
I slightly modified a NAPA Balkamp BK6601141 valve and hooked it up directly to the existing slide control cable (mod just reversed operating direction to match slide words).
I used brass elbows with hose fittings to make corners for tight locations. I ran the hoses down the passenger side of the console near the floor and out thru a hole in the firewall behind the seat.
Routing thru the passenger compartment doesn't add any heat in the cabin unless you are using the heater. The valve completely shuts off flow so the hoses are cool until you move the slide to get heat.
Using hoses and the NAPA valve was a pretty simple, easy way to get the heater functional.
Bayani,

Wish I still had clean access to my tubes....would give it a shot at measurements! Actually got Erica running again today! Runnin....not yet drivin....!

Anyway, I thought there was only one hose up front which needed to be stretched just a hair to fit a 3/4?" fitting on the heater core. (???)

The other side went to the valve, which was slightly under 5/8" if I recall.

I recall sitting in the car staring at this going...."one's too small...the other is too big"...."what's up with that???"

Neat pic's of the tunnel! I have no idea what the engine end of things looks like, in terms of access thru that area of the tunnel....but if you could put the 90 degree bends on that end...and still get them thru the tunnel (engine out most likely???)..and being stainless, would be fantastic! A sure fire thing to do ....next time engine is pulled.....!

Since you will have unique pieces for the left and right tubes.... the 90's would likely need to be "nested" to cleanly make the corner and still allow hoses to connect properly, you could have the one tube that needs 3/4" to match.... you have the one end stretched slightly to 3/4"??? Thinking out loud.....

Love the chassis pic! So those two ears at the top with the holes in them are NOT supposed to be bent forward over the edge of the valance? Hmmmm!!!!

Ciao!
Steve
quote:
Originally posted by Mangusta:
Bayani,

Wish I still had clean access to my tubes....would give it a shot at measurements! Actually got Erica running again today! Runnin....not yet drivin....!

Anyway, I thought there was only one hose up front which needed to be stretched just a hair to fit a 3/4?" fitting on the heater core. (???)

The other side went to the valve, which was slightly under 5/8" if I recall.

I recall sitting in the car staring at this going...."one's too small...the other is too big"...."what's up with that???"

Neat pic's of the tunnel! I have no idea what the engine end of things looks like, in terms of access thru that area of the tunnel....but if you could put the 90 degree bends on that end...and still get them thru the tunnel (engine out most likely???)..and being stainless, would be fantastic! A sure fire thing to do ....next time engine is pulled.....!

Since you will have unique pieces for the left and right tubes.... the 90's would likely need to be "nested" to cleanly make the corner and still allow hoses to connect properly, you could have the one tube that needs 3/4" to match.... you have the one end stretched slightly to 3/4"??? Thinking out loud.....

Love the chassis pic! So those two ears at the top with the holes in them are NOT supposed to be bent forward over the edge of the valance? Hmmmm!!!!

Ciao!
Steve


Thanks Steve,

Actually, the heater core on my '72 looks like it's metric. One was, like you said, slightly above 5/8" more like 16mm) and the end on the heater valve is slightly under under 5/8" (more like 14mm. Is that right?). I'll have to re-measure again to make sure before I commit to swagging or crimping the ends of the heater tubes I'm making.

The real challenge is making the 90s on the engine side. As you said, trying to "nest" the two bends will require the 90 on the driver side to angle up or down, depending on space, then back so it will be parallel to 90 on the passenger side tube. And yes, this is definitely an engine out service.

On my car, The actual tubes to the heater core are 10mm (slightly larger than 3/8") with one end brazed to a 16mm beaded tube fitting. The heater valve side had a female threaded fitting that, from what I read on another thread, to a 3/8"BPPT(British Parallel Pipe Thread?). The beaded tube fitting on the valve is about 18mm?. I wish I had the core out so I could change the ends. I really want to move the heater valve anyway, actually go to an electric heater valve mounted outside the cabin in the engine bay or under the front trunk (if I end up going with an under car heater tube arrangement.

Sorry, I'm just rambling on my ideas for this project. Bear with me here.
Last edited by liv1s
quote:
Originally posted by JFB #05177:
quote:
Originally posted by Mangusta:

...Love the chassis pic! So those two ears at the top with the holes in them are NOT supposed to be bent forward over the edge of the valance? Hmmmm!!!!


I noticed that too! I thought they were flimsy recover hooks. Mine are bent foward over the valance


That car had a major restoration done in the 80s and I think they bent those "recovery hook tabs" back flush with the rails. I think they were originally bent forward towards the front valance like the rest of ours.
Last edited by liv1s
Lots of weird curves, and it's hard to measure...

PM Me your email address, and I will send you a large number of photos to go with the measurements.


Pipe Diameter = .715"

Complex Pipe... (Bottom Pipe)

Anyway - Most complex pipe is the lower one. It has the little bend to get the pipe up and aligned with the exit holes.

NOTE. The lowest pipe is filled with water and goop, because it can't drain out all the way.

Length (Inside of Curve) = 46.5"
Tube Offset (Tail End)= 1"
Rear Bend length = 3"
Straight Section (Middle) = 29"
Straight Section to Heater = 6"


The "S" Shaped Bend has angles of 40*
The Single bend to the heater has an angle of 50*
Main Bend Radius = 6"


Straightest Pipe... (Top Pipe)

Length = 45 7/8"
Only 1 bend - same as the first pipe.

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