Series 3 questions about heating system

Hello everybody
1. There are two hoses going from engine to the heating radiator. One of them has a small valve on it. Which one of these pipes take the water TO the heater ?
2. I opened both of these hoses and although heat was switched on no water was passing through either one. Why do you think this is? The car does not heat up and everything is normal (as normal as one expect from my landy)
3. While I was trying to remove the plastic hose I managed to break the pipe that attached the hose to the body of heater radiator (it was made of plastic and I thought it was metal). How much work is involved in getting that thing out to glue the pipe back or find some other fix?
4. Can I temporarily connect the two hoses together (and bypass the heater) to be able to drive without damaging anything? It seems logical but I thought I check.
Thanks a million in advance

The pipe with the valve on it is the feed pipe to the heater matrix, the valve is operated by the hot/cold over in the cab. If no water was passing through when you disconnected it maybe the valve is sticking or the hose is gunged up. Was the engine running when you disconnected? The water pump needs to be running to push water through. I don't know how much work is involved in question 3 but I doubt if glueing the pipe back together will prove to be a long term fix. You can bypass the heater by connecting the two pipes together without any problem.

Col

Yes you can bypass, no it probably wont glue but you may be able to sleeve it. Its most likely stuck or blocked.

You can still get replacement heater matrix here in the UK, some have plastic top's, some are all metal. About £ 60 to £100 .

Thanks for the replies. This raises another question, should water circulate through heating pipes as it circulate the engine or only when heater is on ? I guess only when the heat is on, right? I am wondering if water is not passing through engine. Although it does not heat up.
I tried to find an explanation of the cooling system of land rovers somewhere and was not able to find anything.
I appreciate if somebody has a link or explanation.

The valve on the engine controls if heat is on or not, open the valve and water goes to the heater matrix and then back into the engine. If valve is on and engine is hot up to running temp then the pipes should be hot. The amount of heat then getting in the cab is dependent on the blower speed [ Sort of ] On my series 3 low speed is warmer, high speed moves more air but it does not get as warm.

Although there are a few owners of series landys who claim their heaters are fine, the majority are almost totally useless. Everything in mine works ok but the blower is like a gnats fart and although heated water is passing through the matrix my lazer temp probe barely detects any change in temperature in the cab, unless it happens to be the hottest day of the year, then the heater makes a noticeable difference. I've tried a bilge fan motor as recommended by many on here but that didn't make much difference either. The way forward is a fuel burning heater.

Col

I think the valve itself restricts water going to the heater unit.
On 90/110/ Defender there is no valve on the pipe to the heater so the water circulates at all time's.
The heat to the cab is controlled by a lever [ the same one on a series that works the valve ] that opens and closes a large flap in the heater box that directs heat into the cab or not.
You could try removing the valve and connecting the pipe direct to the engine [ valve may be gummed up ? ]
You would not then be able to switch heater off but given your location not likely a problem for much of the year. Some control would be had by how much the blower is doing.

Once the engine is up to temp then the circulating coolant should warm the heater matrix as long as the valve on top of the engine is open. The valve can be operated via a cable in the case of a series three or a simple hand turned tap.
Once the matrix (little radiator in the heater box) is hot nothing happens. That’s right, nothing. You then need to switch the fan on to pass cold air over the matrix which is then warmed and into the cab.
My series 3 matrix is on all the time, ie the tap is always open but warm air will not come into the cab until the blower is activated.
Get a garden hose and attach it to the shorter pipe. Flush it through until water (running backwards through the heater) is clean. If it won’t run it’s blocked. You can also remove the pipe from the valve on top of the engine and turn on (run engine) for a few seconds to see if the valve is blocked.
I have heard that removing both pipes and filling just the heater with warm water and a dishwasher tablet works wonders when left overnight then flushed out. Not sure if I would chance it but I can’t see it harming anything.

valve is most likely blocked, the actual aperture is tiny compared to the hose diameter, I had to dig all the crap out of mine with what was a wire coat hanger, once cleaned out cab was as warm as toast.

I would bypass the valve and let water go to the matrix all the time, as said you only get heat in the cab when the blower fan is switched on

I think the aperture is small so it’s the weak link. Much easier cleaning out the valve than the inside of the matrix.

OK let me summarize and see if I got it.
Engine starts and it is cold > Thermostat (When you say valve do you mean thermostat?) is closed so no water is circulating in engine or the heaters > engine warms up to operating temperature > Thermostat opens > water with aid of water pump flows in engine and hoses that go to the heater (no matter on or off) > the optimistic driver turns on the heat in his landy and fan starts to blow the warmed air into the truck > either way water circulate back to radiator and gets cooled > process repeats.

So since I get no water in the hoses either the thermostat is blocked (in this case my truck should heat up and it doesn't) or the pipes and hoses are blocked (which is possible). Now a question is raised: Is the water that goes to the heater is the same that is going through the engine (I mean it is one big loop) or they are separated at some point (two loops), One branch goes to engine and another branch separates and goes to the heaters. If this second case is true then maybe the junction that separates the two is blocked.

I flushed the heater radiators as suggested and they were clean as a whistle, not even a drop of dirt came out. So at least I know the heater is not blocked.

I regards to usefulness of heater I agree with Colthebrummie. Two winters ago when the heater was working it was more for emotional support than actual heat especially with all the cold air coming in from every gap around the windows.

@85Santana3
Rear of engine(if 2.25petrol) on passenger side should be the return for the heater.

If you disconnect the pipes do you see any water movements ?

The thermostat is inside the housing with three bolts holding it. The heater valve is on top of said housing with a cable going to it. Thermostat controls water going to the main radiator, valve controls water going to the heater. It is all one linked system using the same water/coolant.

Heater valve

Hicap phill said:

If you disconnect the pipes do you see any water movements ?

Click to expand...

I removed both pipes and there was no water anywhere.
Thanks for your replies guys. I am going to to do some mechanic work tomorrow (on battery and wiring this time) would be a good opportunity to find where that valve is.
By the way if you installed a new battery and the handle was just like the old one going from left to right do not assume the + and - are in the same place as the old battery. You will burn a lot of wires. Don't ask me how I found this out

So you have an early engine with a valve to stop the water flow.
This prevents the flow through the heater in the summer.
Unlike the later S3 (like @Bobsticle photo)
Which is operated by a cable.
Can you take a photo of the engine?
This will help ID some parts

Ah the joys of getting out and opening the bonnet to turn the heater on! Control the heat from inside, why would anyone want that, next thing the'll want to adjust the mirror without opeing the window,or change down without double de-clutching, where will it end?

Water will flow into the heater is the thermostat is open or closed.

If the valve near the front of the engine is not fully open water will not flow around the heater body.

Just looking at your first post...says Santarna....do you have one of there engines fitted...if so there could be differences.

Santana series 3 engine photo as requested. It is a 2.25 petrol engine and takes about 13L/100 km when it is in a good mode.