300TDi Heater

As winter is beginning to set in Im looking at sorting out some of those little silly jobs. One of the main issues I have on my 300TDi Defender is the heater. Although, as with most 300's it takes 4-5 miles to heat up at which point it blows through warm air, but only when travelling at speed. The main issue I have is that when travelling at low speed or stationary in traffic, there is nothing blowing through the heater. Any ideas what to check.?! The radiator in the heater matrix gets very hot and there are no leaks. The temprature gauge is sits just over halfway.

There are two control wires/levers on the matrix casing itself, one to the side and one on the top, which one controls temprature and which lever opens/closes the flap.?!

I suspect the issue is with the cable/lever or heater switch as the fan is blowing when engaged.

How do you test the switch.?!

Thanks guys

The one on the top controls the heat,make sure it is fully extended,(as far as it will go towards the N/S wing) to set it to hot. (lukewarm!)

Hope this helps.

Luigi Vampa said:

The one on the top controls the heat,make sure it is fully extended,(as far as it will go towards the N/S wing) to set it to hot. (lukewarm!)

Hope this helps.

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Thanks Luigi

If everythings working fine, it should be more than lukewarm, mines a 300, and once up to temp I cant keep my hand over the vent on hot.
if its only luke warm, but the gaugle is about 1/2 way, the heater matrix probably wants cleaning & flushing.

also, your dash vents might be misaligned or the tubes fallen off

and if your blower on full, sometimes they get a bit sticky and it needs a nudge to get it to top whack.

Righty ho I've been out today trying to sort this ruddy thing.

Firstly I removed the dash pod and cleaned and then re-seated the cables. I then realigned the connections on the matrix itself and ensured that they were all working as they should. Next I flushed the system, but still nothing.

Stupidly I then remembered that I hadn't checked the fuse. Upon inspection guess what.?! Yup it was blown. In I popped a new 15amp fuse and swiftly give the old girl a test......NOTHING, zero, zilch! Still it didn't work. Now I'm thinking the motor, or maybe resistor is faulty.

A quick check with the voltmeter and read the following results. With the red connector to the Green/purple wire and black on the the Green/Gray 0.5omh black on the Green/Yellow 0.4omh. If I change the settings the resistance results remain unchanged. The fan moves freely with no obvious obstacles. One thing of note however, when removing the air intake it was full of water, probably a result of recent wet weather, it would appear this has made its way through to the fan as there was a pool of water.

Has anyone or is it even possible to replace the resistor.?!

Okay I've removed the resistor, can someone tell me is it possible to make a replacement or can I purchase just the resistor. I note the genuine replacement part is listed on eBay but come with the loom and is a hefty £90. I'll spend a maximum £20

isn't the resister just for the lower setting anyway? if so you could just run it full speed for now

also have you checked for 12v blower side to see if it's actually getting power?

trax said:

isn't the resister just for the lower setting anyway? if so you could just run it full speed for now

also have you checked for 12v blower side to see if it's actually getting power?

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Yeah I'm getting 12volts!!!

I'm a tad lost to be honest. The fan blows whilst driving, not much, difinately not as much as it used to. When the vehicle is stationary there's nothing, I certainly can not hear the fan operating. If the motor was buggerd you'd expect the fan to be seized but it's not, it moves nice and freely with minimal resistance, although the amount of water in there from the airbox is a concern.

Any ideas.?

Landyfox said:

Yeah I'm getting 12volts!!!

I'm a tad lost to be honest. The fan blows whilst driving, not much, difinately not as much as it used to. When the vehicle is stationary there's nothing, I certainly can not hear the fan operating. If the motor was buggerd you'd expect the fan to be seized but it's not, it moves nice and freely with minimal resistance, although the amount of water in there from the airbox is a concern.

Any ideas.?

Click to expand...

maybe it isn't blowing at speed, but it's just airflow from outside pushing air in?

you deffo have two clicks on the bottom of the fan control and both don't work?

afaik the slower goes via a resister to y'know.. m ake it slower. if you have 12v by the blower but nothing is happening then it sounds like your motor is borked.

if that's the issue, you can either get another, or some people have fitted bilge pumps to boost the output. a 4inch one, cut the legs off and shoved into the plastic intake and wired to the orig.

Bugger I hope it's not the motor!!!!

Is there anyway to test if the motor is faulty whilst it's in situ.?!

Landyfox said:

Bugger I hope it's not the motor!!!!

Is there anyway to test if the motor is faulty whilst it's in situ.?!

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well, earth and power to (iirc) purple and green should make it go. but if you say you have 12v there then it's probs broken.

it isn't too bad to take it off, clamp the hoses, undo jubilees, unclip cables and leccy plug and it's a few bolts.

then you can drill out the rivets to take it apart, give it a clean/paint check wiring state and resistor then rivet it back together... or see if anyone is flogging one local

i might be around in 4-6 weeks if that's any use and it hasn't snowed

trax said:

well, earth and power to (iirc) purple and green should make it go. but if you say you have 12v there then it's probs broken.

it isn't too bad to take it off, clamp the hoses, undo jubilees, unclip cables and leccy plug and it's a few bolts.

then you can drill out the rivets to take it apart, give it a clean/paint check wiring state and resistor then rivet it back together... or see if anyone is flogging one local

i might be around in 4-6 weeks if that's any use and it hasn't snowed

Click to expand...

Good stuff

What would cause the fan to have a pool of water? The fan turns by hand with minimum resistance.

Landyfox said:

What would cause the fan to have a pool of water? The fan turns by hand with minimum resistance.

Click to expand...

the water not coolant?

the rubber fanny on the plastic bit from the air intake could be bunged up and not draining so it spilled down.

spray the garden hose on it the front of the landrover like rain and see what happens

trax said:

the water not coolant?

the rubber fanny on the plastic bit from the air intake could be bunged up and not draining so it spilled down.

spray the garden hose on it the front of the landrover like rain and see what happens

Click to expand...

Yeah it' definitely not my bright orange coolant (joy of red anti-freeze), just plain clear water.

That's what I thought, I'm just a little mystified as to why it isn't draining. The small drain hole on the air intake box isn't blocked, instead it's just appeared to have gathered in the fan. .

seal around the bulkhead? or the one to the intake?

trax said:

seal around the bulkhead? or the one to the intake?

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Oddly both seals look in good order! I think I'll take some photies tomorrow.

I just hope I can get a good used replacemet matrix/motor reasonably priced.

not fancy the bilge blower mod on it?