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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue
Air lock in cooling system

Hi all, I refitted my egr valve and cooler, I re filled the coolant taking it very slowly and stopping to start the engine, then stopping it and putting a bit more in.

anyhow, good news the heater works, not so good is that the bottom hose is cold even when the temp gauge needle is in the middle of the gauge, ire half way between cold and hot.

however if i squeeze the bottom hose the coolant in the reservoir moves, the same happens if i squeeze the top hose.

does it sound like its air locked, the last thing i want to do is fry the engine

perhaps wishful thinking but do you think that if I go for a pint the problem will fix itself Bow down

Post #321067 9th Apr 2017 6:44 pm
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SYFL2



Member Since: 16 Jun 2012
Location: Sheffield
Posts: 2550

2007 Freelander 2 TD4 HSE Auto Stornoway Grey

No that's definitely a two Pinter.

Post #321069 9th Apr 2017 8:38 pm
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littletriple



Member Since: 27 Mar 2014
Location: kent
Posts: 226

United Kingdom 2007 Freelander 2 TD4 HSE Manual Stornoway Grey

if the engine isn't producing enough heat it may not need the rad.

From the manual:
"With the coolant temperature increasing, at 83°C (181°F) the thermostat reacts and commences opening. The by-pass
valve is progressively closed. Hot coolant returning from the engine to the thermal control module is now allowed to pass
through the top hose connection to the radiator. The flow of hot coolant to the radiator now forces cold coolant within the
radiator and bottom hose to flow to the thermal control module.
During the thermostat opening period there is an initial temperature differential of the coolant at both sides of the
thermostat. The thermostat reacts to the temperature differential and partially closes, while the by-pass valve opens
further. The thermostat and by-pass valve continue to oscillate while the coolant temperature increases.
At a coolant temperature of 91°C (196°F) the thermostat is fully opened and the by-pass valve is fully closed. The return
coolant from the engine is now fully circulated through the radiator and bottom hose. Coolant flows through the radiator
from the RH tank to the LH tank, and is cooled by air passing through the matrix. Entrained gases in the radiator escape
through the connected degas line to the coolant reservoir". 1978 Laverda Jota. Stolen...
1980 Honda CBX1000 6cyl.
1978 Laverda Montjuic.
2010 Yamaha MT01.

Post #321071 9th Apr 2017 8:59 pm
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Steve D



Member Since: 19 Jan 2013
Location: Essexshire
Posts: 4092

United Kingdom 

If the heaters getting hot, there's no air in there. Turn the heater to cold and run the engine. It will take absolutely ages on a Diesel engine for the bottom rad hose to get hot and the cooling fan to come on - half an hour is not excessive. As long as the temp gauge stays steady, there's no problem. If the small air bleeed pipe to the expansion bottle is getting hot, you can be pretty sure that there's no air lock. Past: FL2 TD4 HSE Auto
Evoque SD4 Dynamic Lux Auto
Present: Audi A3 S Line.

Post #321072 9th Apr 2017 9:06 pm
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littletriple



Member Since: 27 Mar 2014
Location: kent
Posts: 226

United Kingdom 2007 Freelander 2 TD4 HSE Manual Stornoway Grey

try driving the car a bit to get some more heat into the system? 1978 Laverda Jota. Stolen...
1980 Honda CBX1000 6cyl.
1978 Laverda Montjuic.
2010 Yamaha MT01.

Post #321073 9th Apr 2017 9:23 pm
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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue

hi all, thanks for the input, i am going to take it for a 10 mile drive today. thats as far as I used to be able to go before the engine went into reduced power mode,

Then if there are no coolant leaks I need to double check that everything is good and tight, refit the centre bulkhead then refit the scuttle and wipers again.

Then re run the diagnostics to check if anything else needs sorting apart from the haldex and fuel pump.

Hopefully I will get the haldex changed over easter, if it doesnt rain, if its the haldex ecu that is faulty, there is a landrover specialist in derby who can program the new ecu to my car.

I knew about the haldex problem when I bought the car, I didnt know about the egr cooler problem, the haldex looks like a much simpler job to sort.

Post #321091 10th Apr 2017 7:47 am
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Yorky Bob



Member Since: 28 Apr 2015
Location: Yorkshire
Posts: 4561

United Kingdom 2013 Freelander 2 TD4 GS Manual Firenze Red

A little trick from years ago when some cars were known air lockers was to run up to temperature with the pressure cap off. As the thermostat opened it often released the last of the air in the sytem. Thumbs Up FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Post #321097 10th Apr 2017 9:05 am
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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue

hi bob, thanks for that,

Post #321099 10th Apr 2017 9:25 am
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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue

hi bob, do you think its safe to drive the car like this, the top hose is getting warm and the heaters working as normal, i won't do more than 10 miles in it as a test drive,

I need to put the bulkhead and scuttle back on incase it rains and damages the electrics. but i dont want to do that until i am sure i have fixed the original problem.

Post #321100 10th Apr 2017 9:31 am
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Yorky Bob



Member Since: 28 Apr 2015
Location: Yorkshire
Posts: 4561

United Kingdom 2013 Freelander 2 TD4 GS Manual Firenze Red

The pressure cap off is not a driven method, just on tickover in the drive/garage.

Can't remember the model but some weird ones you had to fit a pressure rig and pump coolant through to get all the air out. Might have been Renault. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Post #321109 10th Apr 2017 11:34 am
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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue

hi bob, apologies if my reply wasnt clear, when i refilled the coolant i did what you described, ie i filled a bit then ran the engine then filled a bit more. and ran the engine on tickover without the cap fitted.
i wouldnt drive the car without the cap fitted in case it boiled dry.

what i mean was, do you think its safe to drive my car with a cold bottom hose but a working heater and a hot top hose.

obviously i dont want to ruin the engine, anyhow i went on my normal route of about 10 miles, its a mixture of 50mph and 30 mph, on my return i ran the diagnostics and the error codes relating to the egr haven't re appeared. so my hours of toil appear to have worked - thank f***.


anyhow this coming weekend if it doesnt p*** down, its off with the haldex, and on with the replacement. The replacement comes with a new ecu, a local chap in derby can reprogram the ecu.

personally so long as the performance is ok i wouldnt bother with fixing the haldex but i think it will fail the mot as the esp warning lights are a fail. so i have no choice.

Post #321152 10th Apr 2017 6:44 pm
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Yorky Bob



Member Since: 28 Apr 2015
Location: Yorkshire
Posts: 4561

United Kingdom 2013 Freelander 2 TD4 GS Manual Firenze Red

What did the parts cost please and where from and any part numbers ? Very Happy FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Post #321159 10th Apr 2017 8:02 pm
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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue

hi, total cost including coolant was about £130

The replacement cooler and egr valve cost £80 from a breakers on ebay, just above the part number there is a date, its stamped as a 2014.

Coolant was about £25 from eurocarparts

Gaskets cost about £8, I bought a gasket for where the egr bolts to the cooler in case I had to assemble them on the engine when refitting but I fitted as one unit.

A gasket for where the cooler bolts to the manifold, the gaskets were from rimmers

I used a can of egr cleaner to clean the egr side and the cooler side before fitting.

If I was having the job done by a garage I would have probably bought a new cooler and a new egr as its a gamble buying secondhand.

I have been out in the car twice now, both times I have done about 10 miles with a mixture of fast A roads and local 30 and 40 mph roads. I have kept the journeys short as I am still concerned that there may be an airlock.

When I returned I ran a diagnostics check and the errors havent returned.

I had been plagued by dpf faults since about 1 month after buying the car, but when I used the diagnostics to check the dpf it indicated that the dpf wasnt full or didnt need regeneration. So I decided to wait until the problem became more apparent.

The bottom hose is getting warm now, I have noticed a whooshing noise so I need to check the hoses.

I removed the plastic pipe that attaches to the turbo to get access to the egr cooler bolts and also I removed the long metal pipe that connects to the inter cooler so I guess its one of these that I have over tightened.

Next job is changing the haldex unit. Thats my job for easter.

Post #321182 11th Apr 2017 7:30 am
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Yorky Bob



Member Since: 28 Apr 2015
Location: Yorkshire
Posts: 4561

United Kingdom 2013 Freelander 2 TD4 GS Manual Firenze Red
EGR

Thanks.

Looks to me as if its going to become a common failure so what about the future ? No more supermarket fuel ? Or a regular cleaning additive like Miller oils sell ?

One of those jobs I guess that is all about time, money, mechanical ability and possibly age. If you can afford the time take off the EGR and spend as long it takes to clean it and refit.

Will report back on how mine goes over the next 48 hours, time I have plenty of and probably some mechanical ability but as a pensioner my days of crawling behind an engine like this are finished.

As for the money I still send the wife to work. Whistle

My intention is to ask for the old EGR back and clean it up for the next rainy day or part with it, there must be scope for members to create an exchange system. Rolling Eyes FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Post #321186 11th Apr 2017 8:03 am
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weekender



Member Since: 11 Mar 2017
Location: derbyshire
Posts: 51

2012 Freelander 2 TD4 XS Manual Baltic Blue

hi, time and very poor access are the issues, but i enjoy working on cars or thats what i keep telling myself.


Refitting the egr was easier than taking it off as i knew where all of the bits went and I took my time making sure I put everything back it took 3 to 4hrs

The only part that i needed access to from below was the air pipe that connects to the turbo,

Next time i wouldnt bother removing the metal pipe that connects to the intercooler as it doesnt improve access to the egr from below.

I still need to refit the centre bulkhead and the sound deadening material but I want to do a bit more running around to make sure there arent any leaks.

the close up picture is of the old egr, on mine the cooler flap it totally siezed.

re ongoing maintenance, as i dont do a lot of miles I guess i will be doing this every couple of years, perhaps just to clean it prevention being better than cure. Next time I will fit a new egr and cooler.

I have uploaded some pics to my gallery.

Post #321195 11th Apr 2017 9:27 am
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