Reply to "heater valve question"

Peter, there are two different production valves. One uses a bent rod, the other has a flat metal arm. Both leaked internally from new. The leverage of the cable dashboard controller is such that it can be adjusted to either be (almost) completely shut off and only half open when heater/defroster is needed, or (factory setting) to open completely but be 1/3 open all the time. This is why it's important to add a ball-valve shut-off to both in and out heater lines, as the valve sees some pressure all the time and the supply hose(s) can rupture at high rpms. When (not if) this happens, the car completely fills with steam and mist, opaquing the windows and usually broiling an ankle. If this happen at high rpms, you are blind and in pain at high speed.

If you meant the valve is externally leaking, both types use a tiny o-ring inside to seal the open/close shaft. Some U.S. vendors stock it but your best bet is to buy a kit of high quality Viton fluorocarbon o-rings from a hardware store; Harbor Freight sells a kit. There should be a proper size o-ring inside, and the kits only cost $15 USD for 50-100 o-rings of different sizes.