Re: Heater hose routing 52

Posted by HH56 On 2016/3/16 18:08:02

What does the mysterious switch look like and where is it located?

The tube under dash is for the defroster. Inside that square black box is a flapper valve operated by the heater/defrost portion of the right lever. It directs air to the cardboard plenum running across the firewall or to the tube or both.

The thermostatic valve should cut off the flow of hot water but it is possible it started leaking and has been disconnected or is not working or cable is misadjusted. You could either repair that or get one of the cable operated on/off valves for the hose and have the temperature valve cable portion of the left lever work that valve instead of the stock valve. Have to make sure you get the correct type orientation on the valve so it works with the cable setup and the on and off will match the control labeling.

The flapper valve in the vent tube under the heater box operated by the right lever air cable should cut the airflow off to the heater so no hot air comes thru. The rubber on those flappers is old and frequently breaks off so it could be leaking air or cable could be misadjusted. In Feb 51 Service Counselor 25 #2 is the procedure to adjust the cables on those dual function levers.