[DeTomaso] adventures in heating (very long, feel free to delete)

Christopher Kimball chrisvkimball at msn.com
Sat Feb 16 22:07:42 EST 2008



For months I've been waiting for the little rubber gasket I ordered , necessary to rebuild my heater valve for my Pre-L '72.  I finally
got tired of waiting and decided to get creative.  Usually when I get creative it's a sure sign of trouble!

I reasoned I could probably find some other kind of valve that might work, so I went to the local automotive store
(a real one, not one of those "what make and model do you have so I can look it up in the computer because I have no real knowledge of cars"
kind of store) and found a stock unit for '68 to '72 AMCs that looked as if it would work.  The male end that mates with the copper tube
under the dash even was the right size with the right thread pattern.  The other tube was the correct size to mate with
the existing heater hose as well.

I went home and modified the existing bracket and installed the unit and it seemed to fit well and operate fine, mechanically
at least.

I then stuck my arm into the engine bay to flip to the "on" position the two heater shut-off valves I had installed for summer driving,
jacked up the back of the car and started pouring water into the coolant bottle.  As I poured, I observed the coolant bottle never seemed to get full.
I assumed it was just the heater hoses filling up, but after about five minutes I became concerned.

When I went to look under the dash to check the valve, I only made it part way around the side of the car before
noticing a huge pool of anti-freeze on the floor of my garage.  That would have been bad enough,
but the pool was being created by a stream of the stuff pouring out from the bottom of my car!

I rushed to the driver's side to peer under the dash only to find coolant flowing out of the copper junction where
it connects to the valve.  It was flowing, I might add, directly onto my new carpet.  I immediately grabbed some towels
(which should have been positioned there in the first place, except I was too much of an optimist) to absorb some of the flow, 
then dashed back to the engine compartment and rammed my arm into its bowels to shut off the flow of coolant.  
In doing so I decimated the inside of my right arm and sliced a finger (I suppose that's to be expected when working on a Pantera).

Once Niagra Falls was under control and the dripping ceased, I unscrewed the copper nut and compared the new valve's threaded pipe 
with the original and found the top of the original threaded part of the valve was conical to interface with the copper tubing to make a seal.  
The AMC valve had only a straight edge.  No wonder the fluid flowed so freely--there was no seal!  

I tried using a rubber, conical-shaped washer, but the leaking persisted.  I feared I had broken the copper pipe
leading into the heater core.

At this point I was so frustrated I almost collapsed into a heap of discouragement.  I knew if I gave up, however,
I'd have to face all the "I told you so" comments from those on the Pantera forum who would have told me
I should have just waited for the new gasket for the original valve, or simply ordered a complete, reconditioned
valve from one of the Pantera parts vendors (but that would have been far too easy...!)

I gathered my thoughts and decided to forge ahead with another "Kimball modification."  I went to the 
hardware store and bought a fitting that had one end the size of the large hose, and the other the size
of the smaller, copper pipe which comes out of the heater core.  Using heater hoses and hose clamps of the appropriate size,
I connected the valve to the large hose and the copper pipe.  I used part of the original bracket to hold
the assembly in place.  Due to the right-angle between the "in" and "out" under-dash hose and pipe, I had to 
form a loop with the smaller heater hose to avoid kinking it, but I manged to keep it out of the way of the wires, other
heater cables and the accelerator pedal.

I refilled the coolant bottle (frequently checking under the dash, of course!) and to my pleasant surprise
there were no leaks.  I jacked up the rear of the car and did the cooling system refill ritual, replaced the
cap and took her for a drive.  No leaks, and the heater works great!  Best of all, unlike the original 
arrangement, I was able to position the cable in such a way as to get the system to be completely
off, and fully on.

Will it last?  Time will tell...

Sincerely,

Chris
#3846





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