Morris Minor Owners Club

Hi, I have a 1964 1000.
The heater is a rather big black box under the dashboard with a sliding switch on it. There with you can choose between off/car/window.
if I choose car or window it always blows hot air. On another place under the dash is a cable-switch witch states 'heater'...it apears to do nothing.
I can't make it to blow cold air...am I doing something wrong or is it broken ?

Does the cable move at all? And is it connected to a valve on the rear of the cylinder head? Does the lever on that also move (assuming it's there and is the cable operated type)?

If the answer is yes to both, then suspect the valve internals, but chances are the cable has seized or the lever/ plunger is stuck.

under the dash is a cable-switch witch states 'heater'...it apears to do nothing.

Hi Pim I assume you are reffering to the control knob which says Heater Push, this works very similar to the choke cable, if its pushed all the way in to the mounting bracket its ON to turn it OFF you need to pull it out, it moves around 5cms, if it doesnt move at all follow the advice given by Packedup.

ok, I check the working of the cable as adviced by Packedup, but what does the Heater Push and the valves connected to it do exactly ?

It controls the flow of water through the heater matrix.

So if I pull it, the air flow should cool down ?

Yes, if the valve is working.

I've seen valves where the rubber bit has fallen off the plunger, or the lever bends but the plunger is well and truly seized up...

I'd suggest disconnecting the cable from the valve and trying the lever by hand if all else fails. If it's stuck and a leak is OK then a little tapping with a small hitting stick might work - Sometimes it frees them off, sometimes it frees them off and results in a leak...

As far as have seen now, it's not getting colder with the Heater Push pulled out, so I have to examen the cable and valve construction. Tnx sofar !

Better to leave the valve open all year round - stops sludge settling out in the heater. Just close the flap on the front of the box if you really don't want the heat. Up here in ecosseland I don't have that problem!

Upto now I've been driving with the Heater Push not pulled out and the heater switch off. Only a problem with de-misting the front screen, it got kind of hot in the car then...

Too much information.

Too much information about heaters ?

Too much information.

About what Steve