Hello folks,

After the record warmth of the summer season, it’s time to enjoy the comfort of heated seats, FBH and a warm, toasty cabin. Or in my case, not really.

Seats and FBH are fine and doing their job perfectly, but if I want a warm cabin when out driving, the temp dials have to be up at max for it to get remotely warm. Anything less than max and it’s just blowing tepid air at best…

Airlock? When I went to see the car before buying it, coolant was low and we topped it up and monitored it before driving off. Since then, the level hasn’t budged. Cracking open the expansion tank when the engine’s hot results in some gargling though, so maybe there’s some air still in there.

Without the aid of any fancy kit, what would you recommend trying to bleed the system fully? I’ve seen a few comments on this already, and it would appear that a number of folks have trouble with this. What’s the current thinking?

In other news, I changed the oil cooler O-rings yesterday (and dropped the bolt down the back of the engine in the process!) but now have an oil-leak-free engine! Easy peasy job and very satisfactory results! Viton 611 O-rings in place and holding!

is the red/blue dial in the very centre set to the middle between red and blue, or is it all the way over to blue ? The dial is meant to be an offset to the temp setting on the main dials ... so if you have it to blue, then it'll blowing colder than what the dial is set at (upto 5degC difference I think ). Equally it can offset to a hotter temp if you push it towards the red. Having it in the middle means that it blows the same as dial setting.

Regarding bleeding, its been a while, but there may be a bleed screw you can undo on a pipe near the expansion tank which will bleed air till coolant flows out.

If you run without the expansion cap on, then yes, you will should see a constant flow of coolant through the tank. V8 or else ...

fmgl322 wrote:

Hello folks,

After the record warmth of the summer season, it’s time to enjoy the comfort of heated seats, FBH and a warm, toasty cabin. Or in my case, not really.

Seats and FBH are fine and doing their job perfectly, but if I want a warm cabin when out driving, the temp dials have to be up at max for it to get remotely warm. Anything less than max and it’s just blowing tepid air at best…

Airlock? When I went to see the car before buying it, coolant was low and we topped it up and monitored it before driving off. Since then, the level hasn’t budged. Cracking open the expansion tank when the engine’s hot results in some gargling though, so maybe there’s some air still in there.

Without the aid of any fancy kit, what would you recommend trying to bleed the system fully? I’ve seen a few comments on this already, and it would appear that a number of folks have trouble with this. What’s the current thinking?

In other news, I changed the oil cooler O-rings yesterday (and dropped the bolt down the back of the engine in the process!) but now have an oil-leak-free engine! Easy peasy job and very satisfactory results! Viton 611 O-rings in place and holding!

Which engine do you have? The bleed procedure is different depending on engine.

No special tools are required for bleeding, so long as you follow the workshop manual steps.

If it's the 4.4 TDV8, the bleed screw is slightly to the right of the expansion tank on a radiator hose. It's a big plastic plug with a cross head for a screwdriver in.

Here's the bleed procedure for the 4.4 TDV8:

Click image to enlarge

Click image to enlarge

A point to note, there are other possible causes:

- One could be the final stage resistor (hedgehog), although less likely on a car 10 years old
- internal cabin temperature sensor (can be monitored with IID) and again, unlikely on the 2011-2012 cars which had a different climate panel to earlier cars
- faulty pressure control valve on the air con compressor can also cause lack of cabin heat. I had a similar issue where the cabin would cool but not adequately heat almost at random in winter. The cause was the air con compressor. 2015 Range Rover Autobiography 4.4 SDV8

Sorry, should have said, it’s a 2012 TDV8 4.4. The O-rings repair should have given it away!😂

See above. 2015 Range Rover Autobiography 4.4 SDV8

I presume the engine is fully upto temperature. Cracking open the expansion cap with a fully upto temperature engine is a seriously dangerous thing to do.

My 2012 TDV8 was fine and warm when the fuel burning heater was on (under 5 degrees external temperature) but above that the heating was a bit disappointing. Modern diesels are so efficient that they don't generate that much heat, and so need the fbh for colder times. You could also have a problem with the final stage resistor/sticking of flaps in the heating ducts and maybe replacing/freeing in that area could help. I tended to use the auto setting and generally just leave it at the set temperature, but when it was say 6 to 12 degrees and not sunny it needed to be turned up a bit, though not to max. Only Range Rovers since 1988

Thanks for your replies so far.

Update: I took the car out for a blast on the autobahn to get it up to temp then carried out the bleeding procedure as posted above. No air in the system. Heating at max, blower at max; unbearably hot in the car. Bingo! Coolant nice and hot, level spot on.

Not so out and about. Out on a drive anything other than max temp was lukewarm at best (yes, the cold/warm slider was in the right position!). After leaving the car to stand for 30 mins while the Mrs insisted we potter round ikea, things were even colder on our return journey…

I’m guessing there’s a sensor or some electronics playing up somewhere along the line… Just out of interest: there’s no difference with A/C on or off…

Thermostat stuck in the open position? BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Thought about that (thermostat) but the engine temp rises normally and the top hose (bleed hose) only got hot once everything else was up to temp. I’m guessing the thermostat is working…

Thermostat may be working but at the wrong temperature? I had a Merc Sprinter that always ran with a decent temperature showing on the guage but the heater was rubbish unless it was working hard eg towing my caravan 2000kg.

I changed the thermostat, the difference was unbelievable, I couldnt keep hand over the vents on hot it burned me. The old thermostat looked ok, opened in a pan of hot water etc. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Hi there, a few of us have had issues with heating have a look at this post it may help and good luck.
https://www.fullfatrr.com/forum/topic54004.html Also own a 1976 Land Rover 101 3.5 V8.
Previously owned 1991 Range Rover Vogue 3.9 V8.

fmgl322 wrote:

Thought about that (thermostat) but the engine temp rises normally and the top hose (bleed hose) only got hot once everything else was up to temp. I’m guessing the thermostat is working…

This does seem to be a common issue. I’m tempted to get the thermostat changed now. I’m going to be deep in the engine soon enough doing the oil cooler gaskets and donut hoses, so why not just add the thermostat to the (slowly growing) list of things to do.

Haven’t been able to locate a thermostat change cheat-sheet on the forum yet - easy to do (he asked, knowing what the answer is likely to be…)?