Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
Strange thermostat behavior D3 TDV6, the problems continue
Hello, after recurring problems with the coolant in my D3, I can only say that it was expelled through the closing valve of the expansion tank as I mentioned in another recent topic, and after making the decision to replace the thermostat in order to cancel the coolant overflows, It seems that these have been contained with the new thermostat, but now something unwanted happens... the D3 now takes much longer than usual to reach its use temperature and once reached(PHOTO1)it never exceeds it towards hot, however it loses it towards the cold, for example in a wide descent, is placed halfway between the cold point and the point of normal use (PHOTO2), as is evident this did not happen before, the temperature never fluctuated after reaching the normal temperature of use. Please, any idea what could be happening? air entry into the system? Anything you tell me helps me give clues to an LR mechanic, from the official dealership, who says that he has no idea about it 😵💫…..thank you very much in advance everyone and Merry Christmas!! 👍🏼
Click image to enlarge
Click image to enlarge
lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
Last edited by ruben on 11th Jan 2024 11:02 pm. Edited 1 time in total
18th Dec 2023 5:11 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4762
Ruben the thermostat never stays fully open or closed during it's operation. It's designed to constantly fluctuate (open/close) so that an optimal operating temperature can be obtained in all conditions during each cycle.
It looks as if you might well have air in the system because it appears to be behaving as if the thermostat has been removed. It could be a faulty thermostat, but unlikely. Get it warmed up and try bleeding via the three bleed valves, but be prepared to allow a decent flow out of coolant.yµ (idµ - eAµ) ψ=mψ
18th Dec 2023 7:03 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
noted, thank you very much!!lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
18th Dec 2023 7:30 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
update
I went to the local Land Rover dealership, currently the only one, they tell me that the cooling system does not bleed, that it is self-bleeding and that it automatically expels the air by itself...why does it have 3 bleeders? I ask myself? confirmed...this world is ending..does the explanation that the dealership gives me have any semblance of reality? I have no arguments against them, they replaced my thermostat, I don't know if they put in one of Chinese origin, I hope not, I don't know what happened but I find it strange that it was damaged from origin when it was new...but they are closed with the purge issue, They prefer to put another thermostat, it is in the ordering phase…..now running always in cool…and I dont like it!.will have to look for the procedure somewhere and try to do it myself without hurting myself...since I am as similar to a mechanic as an egg is to a chestnut...we will see...by the way, does anyone have the detailed procedure to see? if I can do it?? thanks guys!lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
19th Dec 2023 1:12 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4762
See section 303 - 03C, which describes a full drain & bleed but some elements may not be relevant (eg rear heater hoses) if you don't have one.
I would suggest in the first instance you don't need to drain the system, but if there is an air lock it can be stubborn sometimes to purge! Make sure the heater is in the max position and that you have enough spare coolant (same as what's already in it) to replenish any lost. There is another bleeder on the EGR crossover pipe which is not mentioned in this section of the manual. The pipe can and does often air lock during coolant filling as its the highest point in the cooling system. However, if you can't open it just leave it as they can easily snap, and do not overtighten any of them. They become brittle over time, so once they come to a stop just a small nip up will do.
If you want to inspect the thermostat it is located remotely in the pipework below the radiator. To access it you need to remove the 4 bolts which hold the access panel beneath the radiator immediately in front of the engine protection cover.
Member Since: 15 Jan 2016
Location: GL
Posts: 10406
Petrol ones are self bleeding. But not the diesels.
Penny pinching.
19th Dec 2023 3:27 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
many many thanks guys!!lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
19th Dec 2023 9:43 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
and…now solved, thanks guys and merry christmas!! 👍🏼👍🏼lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
22nd Dec 2023 1:38 pm
disco chris
Member Since: 25 Apr 2022
Location: London
Posts: 251
Well done, what was the issue in the end?
22nd Dec 2023 2:41 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
In the absence of further observation, I must conclude that it was my 17-year-old, 370,000 km thermostat...and a water circuit negligently purged of air by my dealer!! Thanks for your interest!!lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
22nd Dec 2023 2:48 pm
kajtzu
Member Since: 11 Aug 2017
Location: Helsinki
Posts: 6586
Pete K wrote:
Petrol ones are self bleeding. But not the diesels.
Penny pinching.
The 4.4 liter petrol is notoriously difficult to bleed, absolutely not self-bleeding anything.
22nd Dec 2023 4:07 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
UPDATE, the problems continue, of course, in principle, with the NEW expander base and the NEW valve plug (110 psi) and the NEW thermostat, now there are no more coolant spills, BUT, after purging the system, I don't know if enough the dealer says yes, the TEMPERATURE of the engine is now SOMETHING ERRATIC, it never goes from the medium level upwards, but it takes much longer to reach it than before, and it is maintained only when there is a certain level of demand on the engine, as soon as you start a medium long descent for example or simply idling stopped, THE TEMPERATURE DROP STRANGELY HALFWAY BETWEEN THE MIDDLE POINT AND THE COLD POINT. Is it due to any known symptoms? I'm missing something? thanks in advance!!
Click image to enlarge
lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
11th Jan 2024 10:55 pm
Pete K
Member Since: 15 Jan 2016
Location: GL
Posts: 10406
Do you have an FBH heater fitted?
Does it work?
What it the outside temp in the mornings? 4C or lower?
The heater is there to keep the engine warm
As a temp fix, cover behind half the grill with card until spring/summer
11th Jan 2024 11:15 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 4762
I can only think of three scenarios that would cause your symptoms. A malfunctioning thermostat (stuck open) An air lock. (though this usually cause a temp spike!) Or, incorrectly connected thermostat pipework.
What is the heat level in the car like, and does it change much with the temp gauge readings? Do you have rear passenger heating?yµ (idµ - eAµ) ψ=mψ
11th Jan 2024 11:17 pm
ruben D3 Decade
Member Since: 26 Sep 2006
Location: ASTURIAS
Posts: 2401
Hello and thanks, well….yes I have FBH, and it seems to work well with temperatures less than or equal to 5 degrees C with the air conditioning on and enough fuel in the tank. On the other hand, I can notice that the heating seems to heat a little less, I do not have rear air conditioning. As for the possibility of a wrong installation, I have raised it as a possibility, but the dealer swears that there is no possibility of a wrong connection, that the configuration of the thermostat itself and the pipes prevent the possibility of an error...I can't know, I can only trust in this, but the reality is that I see them lost and I don't trust in the correct assembly... I have looked for photographs that I could compare with mine but I can't find anything on the internet!lost in translation!
DISCOVERY 3 SE man. TDV6 2006, my true love!
DEFENDER 2 SE D I6 MHEV 2024, other live.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
