Heater controls - getting ready for Winter

[kernowman]

My heater only operates through the screen vents despite the position of the control knob. Has anybody got a diagram of the vacuum system for the heater controls as I am finding it difficult to follow all the little red and black vacuum pipes. One has also been disconnected (goes to a lower water hose with a valve) and blocked off with a screw which doesn't seem very good:thumbdwn: Any help would be much appreciated - never know these days when it is going to get cold!!

 

[BIGHVM]

Hmm- Marty has a problem with his cooling also- he says to me that his heater is hot no matter what the setting? And even though we back flushed it and filled it with anti freeze and a new thermostate- that after not driving it for 2 or more weeks, it goes to near boiling first time then is fine after that!

I think he has two problems- the heater and another airlock- a leak someplace letting in air.......could even I guess be something to do with the suspect heater operation?
What do you all think?

 

[kernowman]

Haven't a great deal of experience on heaters, but I would assume there is a valve in the heater pipes somewhere that controls the flow of water. This I would have thought is coupled to the control knob so the water flow is varied depending on the setting, thus varying the heat output. This is one of the reasons that I am looking for a vacuum diagram, as all these things appear to be vacuum controlled. I am actually wondering if this valve is the one that is disconnected on mine. The valve I am looking at is just under the alternator.

 

[kevin p]

Hi guys. I think you must have a vacuum leak somewhere. On mine with the engine off, so its quiet, if i turn the knob for the direction setting, I can hear air being expelled from behind the ash tray area.

 

[kernowman]

I think you must have a vacuum leak somewhere.

Reckon so, having looked more at the system. Looks as if one small vacuum leak will stop everything from operating. Pipes and vacuum motors everywhere:thumbdwn: Nutcase must have designed the system.

 

[kevin p]

I have got a very basic schematic diagram of the vacuum system on a Ford CD. It certainly doesn't show where all the pipes go, just the basic connections. I've become an 'Elite' member so as I could post pictures etc. Still don't understand how to do it...... otherwise I would send the info I've got.
I believe the 'Chilton' manual for the Explorer states it has the Vacuum system components in it. Might be worth a look to make sure.
Kev.
p.s. come to think of it now, when I got my Ex 6 years ago, the vacuum pipe going to the valve under the alternator was disconnected. I just thought it had come apart, so reconnected it and thought no more about it.

 

[kernowman]

I've also got a very basic diagram which is on the Mitchell CD for the Ex - not much use as, like yours, does not show all the pipes. Also have a 'Chilton' - my edition refers to it, but that is about all. Will take the plunge as soon as I can and start tracing the vac pipes. Will try and get it down in diagram form as it looks as if it could be useful to a few people. Strange you had the same pipe disconnected as me - I now think this valve under the alternator is just a on/off water valve to the heater. It looks as if the temperature is controlled by an air mix flap which is electrically controlled from the centre knob. This flap appears to be on the main heater plenum (lovely word, that)