1999 Ford Ka Heater Control Valve Repair

At the time of writing this document the car I use and own is a 1999 Ford Ka. It is a lovely wee car that offers an excellent blend of manueverability, cabin space and acceptable power to give you a good small city car. I've owned this one since buying it as an ex-demo item from the car dealer and it has by and large given me good service.

However much as I love the car I will never buy a Ford again.

This isn't because the car design is bad at all. Indeed I love this car and the little design touches that show someone thought about the use of the car carefully. No I won't buy a Ford again because while the design is pretty sound Ford decided to cheap out on the materials used. To give you an idea in this cars nine and a half year life it has had :-

My suspicion is that this car has been either shipped on deck or left on the wharf for an extended period to engender a lot of these problems. It seems to be unusually suffering from rust issues - even my previous car, a 1972 Ford Escort had less problems than this newer one has. What really rips my rationbook is that Ford itself acknowledges these flaws in succesive models of the car but refuses to deal with them for the people who bought the early model. Later Ka's come with an aluminium oil sump and alloy wheels as standard precisely because these are both well known defects with the car.

Speaking of defects this leads me to the point of this page. Recently my heater packed in so that I was only getting cold air supplied in the car. Given that it is summer verging on autumn at the time this isn't a huge issue till you have a wet humid day where you are trying to keep the front windscreen from fogging. At which point not having heat to dry the incoming air out becomes very much an issue - a dangerous issue that I needed to fix. At the same time the fan speed control had also partially died with the lowest fan speed not working. So thanks to the wonders of the internet and some parts ordering I decided to try and fix these myself.

Now the fan speed is relatively easy - a resistor pack mounted in the passenger footwell space provides the speed step down. This is secured by one screw and is comfortably reachable from inside the car. So that got replaced in the carpack of the parts supplier. One problem down, one to go. The research I'd done on the heating issue pointed firmly to the heater control valve. It further indicated that this was a pretty simple part to replace but while moderately detailed textual descriptions exist no images of how to do this are out there. I figure I'd both have a go at doing this and at documenting it a bit to give others a more visual path to follow.

Heater control valve image. So here is the part in its new glory the hooks face forward and grasp the engine bulkhead between the engine bay and the passenger compartment. Fundmentally it is a simply device - the solenoid on the side accepts a varying voltage and as such varies how much pressue it exerts on a value. That regulates the speed of water flow and consequently how much hot water is fed from the engine to warm the air. This is another fairly widely acknowledged minor design fault with the Ka's. These solenoids tend to fail after a few years mostly from weathering damage as while this unit is buried beneath plastic facia it isn't in a sealed space and water does tend to pass through. Certainly the solenoid I pulled out was fairly pitted and looked like it had jammed. It also hadn't aged well - the plastic had become quite brittle. Something that surprised me a little as usually plastic ages from ultraviolet exposure breaking the plastic molecules up. Here sunlight wasn't an issue so I have to assume, seeing as it was the hot water feed side that was the most feeble, that it is thermal stress occuring.

Now I should make something very clear here. I am not a mechanic and this is my first go at a major bit of car servicing. I certainly have tinkered with repairing the radio system (Ford chose heavy inflexible wire for the door pass through leads to the speakers, this means they will snap as the action of opening and closing the door wears them.) but actually tinkering with an engine component like this is something new to me. This I think is the other reason for putting this up - if I can do this succesfully then anyone with a mild bit of mechanical aptitude should have the confidence to give it a whirl as well.

Windscreen wiper detail image. Step One - remove the windscreen wipers. You need to remove the plastic facia that is underneath them so off they come. Hidden under that end covering is the locking nut which holds the wipers on along with a washer to help the nut not move. It is worth noting that when putting these wipers back on you don't want to over tension them - just tight enough to be firm will do. Too tight and you can cause the windscreen motor to strain.

I must apologise for the blurriness of the shot here. Because I was using my good digital camera and I was getting oil, grease and other gluck over my hands while working on this (and I had already been looking in the engine bay to decide if I could move the water expansion tank or not, so very dirty hands) I wasn't operating the camera well. In particular I was trusting the shots were coming out okay instead of double checking them on the LCD screen. Silly me I know but even with the blurr this shot is clear enough to see where the locking nut lurks. So it wasn't a total disaster.

With windscreen wipers removed detail image. Step Two - with the wipers off begin to remove the plastic facia. This is held on by a set of six screws covered with plastic lugs just underneath the windscreen but on the outside of the car. With a sharp knife pop the lugs out and unscrew them. Now you need to open the bonnet. Three more fixing screws are at the bottom of the top piece of plastic facia and in recessed pockets. These three need to come out as well. They attach the top plastic pieces to a plastic divider in the engine bay. I've marked them in the photograph with yellow circles to make it clear where they hide. Once they are out you should be able to lift the top plastic piece out. Be aware that the windscreen washer nozzles are connected by a hose that needs to be unplugged before you can fully pull the plastic off. This hose has a handy disconnection point near the nozzle end you can use. The top piece splits into two parts and can be put to one side. On the top of the plastic divider is some split rubber hosing acting as a vibration damper for the bonnet (I think). This needs to be pulled off as well.

You most likely will find a lot of debris and gluck in here. Spiders it seems just love the grill in the facia and set up home in here. On top of that dirt and other random crap will have collected underneath the facia. I took the opportunity of having the cover off to clean the area a bit. Not vital but makes working in this space more pleasant. A bucket with some water and a damp cloth do the job nicely.

Sighting the feeder hoses detail image. Step Three - sighting the beast's lair. Technically this occured before step two back there but what the hey. Before I got too keen in pulling things apart, and possibly not getting them back together again, I wanted to see where the valve lived and how tricky it was going to be to get to it. I've circled the first sign I had by looking for the feeder hoses that connect to the valve assembley from the engine. As you can see it is right at the back in the engine bay in the middle of the bulkhead. Not the easiest of locations to get to if you happen to be short. It is worth pointing out here that this location means you really do need a fully cold engine before doing this work. You are going to have to squeeze your hands around the top of the engine block to access behind the plastic divider. Obvious point I know but getting burns on your hands isn't funny so I'll be a little obvious.

I also marked out the rubber hose I talked about in step two just to be clear.

What is under the facia detail image. Step 4 - work on the plastic divider. With the top plastic facia and rubber damping hose off you can now work on freeing up the plastic divider itself. This is fixed by six screws. Two on either side of the engine bay under the bonnet hinges. Nice and easy to get at. One in the centre connecting to a metal linking arm that connects to the car body just under the windscreen. Also nice and easy to get to. One on the top of the plastic divider panel just to side of its central split. Finally two hidden down behind the engine slightly to the right of the feeder hoses going to the heater control valve. These are nasty to get at and require winkling your hand in over the top of the engine block but underneath what I think is the vacuum feeder tube. Patience and a careful approach is advised. Be aware that you will likely drop these screws - fortunately directly beneath them is pretty muuch clear space so they will fall out of the engine bay to the ground. It isn't so bad removing them but fitting them back in is perhaps the trickiest part of the entire job. You want as long a phillips head screwdriver as you can get your hands on for this. The longer the better.

The control valve revealed detail image. With all the screws out the plastic divider also splits in two and can be manipulated a fair bit. Now a chunk of the wiring loom runs along the top of the divider and is clipped in place. You can open these clips and release the wiring which then lets you bend one half of the plastic divider out of the way. Ford procedure is to unclip everything off the divider and remove it entirely. That seemed like entirely too much work for my liking. So as you can see in the image I just bent it up enough to keep it out of my way without having to do much more.

Congratulations! The bulk of the work is now out of the way and the valve itself is now exposed and ready to be replaced.

Step Six - replace the valve. Now the valve assembly is held in place by its hooks and the hoses attached to it. Begin to remove the hoses by squeezing the metal ring clamps together to loosen them and move them up the hose away from the valve assembly. I found an adjustable grip tool worked well for this - simply set the appropriate grip width and you can adjust these clamps fairly easily. To prevent mix ups I disconnected one hose at a time and immediately attached it to the same port on the replacement valve. The hooks on the valve itself and the solenoid give you an easy visual orientation and surprisingly little water comes out. The valve itself is mounted slightly above the engine and I think the heater matrix inside the car is below it too - so most of the water is perfectly happy to stay where it is.

An important point to note, you are messing with the cars cooling system. Internal combustion engines run hot and do rely heavily on the cooling system to keep them from self destructing. The cooling system also runs at about 1.5 to 2 times atmospheric pressure so when putting the hoses on the new valve ensure they are firmly seated and that the metal ring clamp is over the bulge at the end of the valve fitting point and it clamps on the flat surface. It was the idea that I could destroy the engine that I found most daunting about the whole project. While you do need to be careful to ensure the hoses are correctly sealed it isn't too bad a job. Just be methodical here.

Once the replacement valve is clipped on with the hoses and you have reattached it's electrical connection then place the plastic divider back, reclip the wiring loom and open the cap on your water expansion tank. While not much water has been lost some has so you need to slightly top up the radiator fluid level as well as get the air bubbles out. Check that you have everything clear of the engine and turn the engine over for a few seconds - about half a minute or so. What you are really doing here is running the waterpump to ciculate water and by leaving the expansion cap open you let those bubbles work their way out. Keep an eye open for water steaming from the expansion tank - you don't want this to happen as it is a good sign you are cooking the engine. Once you have done a brief turn over with the cap off, switch off and replace the water expansion tank cap.

Run the engine again and while it is idling in neutral (ensure it is in neutral and the parking brake is on.) check under the car for leaks. Also turn your heater setting to hot and verify that nice hot air is now coming out your air vents. If so success! If you do have leaks then you are going to have to let the engine cool, get back in to the valve and see which ring clamp you haven't put back on properly...

From here on in it is pretty much the steps in reverse. I can't recommend enough that long magnetised phillips head screwdriver for putting the bottom screws of the plastic divider back in. My screwdriver was a fraction too short and I kept dropping the things as a result of not quite having enough space for screwdriver, hands and getting the screw in place. I found borrowing a longer screwdriver from work so the handle of the screwdriver wasn't in confined spaces as well as using the adjustable grip tool to hold the screw while place it worked well. And thats it.

So far the car has survived several motorway trips and is back into regular work runs each day. I also have nice hot air once again as I need it. Of course the car, being a car, has now decided I don't quite love it enough for its needs and has cracked its windscreen. Thankfully that is covered by insurance and professionals can deal with it. All in all hopefully these pictures will give the next Ka owner who wants to do this job an easier time along with the knowledge of exactly what to look for.

Philip R. Banks
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