Originally Posted by Mark+4
Looking at 2 Mods this winter.
1. Heat Shielding the Air intake
2. Adding a Shutoff or Bypass to the Heater Matrix.

Fascinating and VERY helpful Mark. Some things don't change. The one thing the older trad Morgans (pre 2000) and their regularly changing cabin heater systems had in common, was that they would heat the cabin, even when the shutoff valve was forced closed and the cabin vents were shut. Our southern brethren would (and still do) block the air vent into the heater matrix box to be a bit cooler. Without a shutoff valve, they would be unbearable. Admittedly, the original shutoff valves were anything but stellar and always suspect. The cable that actuated them and hose routing were both psychedelic..so one is never sure they are closed fully or partially or at all. They break frequently. Most change them to something more sensible. I am attaching images of the original (try to figure out the bizarre routing for its hoses!) and the type most switch to. ( I use a solenoid/) For the interest of that group.The bypass piece, if any, was fit to the heater hoses closer to the engine. The primary goal was to stop the hot coolant flow to the matrix so either hose, coming or going, could be used.for the shutoff. Enough history though the overwhelming majority of the trads on the road are pre-2000. [/i]

I am I correct in assuming the car was not moving during your observations and you were IN the car?

gmg

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