One subject that comes up from time to time relates to cockpit heater and windshield demister assemblies that AC Cars installed in most Cobras. (427 Cobras received a much different design by another manufacturer.)
These systems are installed on the cockpit side of the engine bay fire wall. Only the lower parts of the assembly are easy to see while installed in the car. Taking an assembly out just to take pictures would be a lot of work never mind dealing with coolant getting loose in the cockpit once the coolant hoses are disconnected. (It didn't take but once to learn to flush the core well with tap water very well and use very low pressure (way less than 10 psig indicated) compressed air purge most of the water out before disconnecting the coolant lines to the core.)
Yesterday I reassembled the heater/demister unit for CSX2551. It has been apart and out of the car for several decades. It was passed old owner of the car to new owner several times. It was nasty. Somewhere in time somebody removed it, probably because the core was leaking around both brass nipples, did just a little clean up, glass bead blasted it all over inside and out just enough to remove the worst corrosion and dried
antifreeze, and then painted everything but the vent hoses with two different shades of paint (one bright silver and one metallic gray). The wires, fasteners, vibration isolators, plastic fan blade, and rubber elbows for the demister hoses were painted over at least once. There was a fairly thick layer of crust inside the bottom of the housing that was painted over also. In all the handling the housing and mounting tabs got dented and bent. It looked pretty rough and was missing some small parts.
I robbed small parts required from the remains of the main assembly from CSX2332 that I bought circa 1985 for parts, also includes are some small parts from CSX2108 removed when the car went racing when new. I mostly removed the silver and metallic gray paint somebody applied long ago and repaired the housing. I stripped the paint chemically and then soaked in one of the modern ‘safe’ rust removers for days. These housings have large overlap and spot weld together fabrication details. I used standard metal working tools to work out the worst dents and bends. Everything I could get to, which was most of it, was mechanically wire brushed to remove most of the evidence of being glass bead blasted. This is not a restoration, just repairs. I did not hunt down an exact color match for the gray paint, it is close, but not exact. I did use a commercial metal treatment to put an iron phosphate and nickel surface conversion on the steel housing for paint adhesion and corrosion creep resistance. I did not prime and sand to fill rust pits or scratches it received over the decades. This isn’t a restoration to day one so the finish of most metal parts is whatever it was when at least most of the silver and metallic gray paint was removed. The mounting fasteners are new old stock ones I rounded up. It took some searching but I found some appropriate brass tube to cut some nipples (not shown) for the engine bay junctions in the heater hoses. I have never seen an original tube for sale but they were cut with a normal tubing cutter for Cobras.
Notes:
1) The first batch of chassis split between shipment to east and west coasts didn't have heater/demister systems. Those very early cars didn't have any heater/demister features of what would become standard soon after.
2a) Heater assemblies installed by AC Cars once heaters were added to the specifications for new chassis, usually had a maker's identification (DELANAIR brand name tag) tag affixed to their cockpit sides up to about CSX2200. CSX2201 and later units made to work with Ford electrical systems didn't have tags any more as far as I know. (The tags were reproduced in the 1990s but are now very rare again.)
2b) The exact design and materials of construction for the elongated ducts that attach to the underside of the cowl varied over time. In hunting replacement parts for any given original Cobra you want to determine which type was being used in your car’s time frame.
3) The dash control switch and wire loom shown in my Delaney Gallay Cobra Heater System Components album are for CSX2201 and later cars.
4) Not shown are the "DOUBLE GRIP CHENEY 087S/0" hose clamps AC Cars installed at the heater core under the dash cowl.
5) Not shown are the English made and style spiral wrapped long leg elbow hoses attached by AC Cars to the heater core.
6) Not shown are the rounded radii grommets in the firewall for heater hoses.
7) Not shown are the two known aircraft types (cross sections) of lashing cord used to tie supply and return hoses together between engine and firewall. The cord used on heater hoses may or may not have been the same used to lash speedometer cables and the main fuel lines to the left side main frame tubes, i.e. any given car could have had just one type cord or both types of cord depending on which technician(s) did the installation(s) and what they had to so it with.
8) Not shown is the coolant shut off valve installed in the intake manifold. The general design of the valve is very common and was used by many car makers for decades in different sizes and heights. The exact one used in Cobras has been so far just found in an original Cobra or as a spare part purchased from Shelby American in the mid 1960s. One peculiarity is the threaded stem. The vast majority of parts from the 1940s through 1960s had brass stems. The stem in the valves used in Cobras is plated steel with a faint yellow dichromate conversion coating. If a good corrosion resistant
antifreeze was not used the stems would corrode badly. Note: The standard valve for a 427 Cobra is a different part and is even rarer than what Cobras used.
9) Not shown are the two designs of formed aluminum tubing between water pump and expansion tank that include side arm take offs for coolant hoses for the heater core circuit. Cars using 1962 model year Corvette Harrison made radiators and expansion tanks received the original design tube for a car with a heater while most cars, using Cobra only McCord made radiators and expansion tanks, received a second design.
Anyway, assembled and ready to go into a driver quality car was a good time to stop and take a few pictures. This is not a restoration guide. (Originally the motors had some text ink stamped on them and usually a paper sticker too. Leaks allow fluid to run over the areas with these details which pretty much destroys those details.) I uploaded a collection of images to an album. The link below should work.
Cheers.
Dan
http://www.clubcobra.com/photopost/s...y.php/cat/3225