1.8 cooling issues - Bottom rad hose cold!

Hi all.
I have an issue with the cooling system of my 1.8 Freelander. Looking for help but please read the following first....

*This issue has been covered again and again on this and other forums, the problem is that a lot of people offer their help and well-intended advice, the thread descends into off-topic waffle and 'two-penneth offering' plus; the original poster doesn't ever tell us how they resolved the issue in the end!
Not helpful to anyone else looking for answers

So, if anyone reading this has ever experienced the following symptoms, and managed to fix the issue, please, please, please post a reply! I have tried the obvious stuff, so please no replies stating the obvious!

Rant over. *sorry* I'm tired, frustrated and REALLY need my car back on the road ASAP!

So the issue is: Engine runs all day at idle just fine, except the top rad hose (from engine) gets really hot but the bottom rad hose (return feed to thermostat) stays cold, no matter how long I leave the engine idling or how much I revv it up, coolant doesnt seem to be cycling through the radiator and around the rest of the system.

If I go for a drive in the car, say 5 miles or so the heat in the top of the system becoms such that coolant is sent back into the expansion bottle and starts to bubble out of the cap. Temp gauge on dash never really rises above half way mark, the radiator fans kick-in at around same time as coolant starts to bubble, so the car knows it is starting to overheat ( temp sensor must work).

Heres the stuff I've tried over the weekend so far... so if your suggestion is mentioned here, I don't need to hear about it again unless you have anything new to contribute.

I have taken every hose off the car and flushed it through to check for blockages.

I have flushed the radiator through with a hosepipe, in both directions, clean water runs through.

I have flushed the heater matrix through to clean and check for blockages.

I have removed old thermostat, bought brand new one, tested that it opens with boiling water and fitted it.

I have bought a can of radiator flush and followed the instructions, to flush/ clean any crud in the system.

I have ditched the blue coolant that was in the system ( not me) and bought 5litres of red OAT coolant.

The car had a new water pump fitted in May this year, so is unlikely to be at fault, but have not ruled this out completely. When I removed the top hose with engine running, cooland appeared to pump out so I presume the pump works, however I guess pressure/heat could have been forcing coolant out. Anyone who can provide instructions for testing whether pump is working please contribute.

The system has been filled and bled correctly, including blowing into inlet manifold jiggle valve prior to filling, bleeding from lower bleed screw first, followed by top screw etc.

I spent hours (literally hours) today with the engine running at various speeds, bleeding air out the the top screw and trying to get coolant cycling around the system properly, but the same symptoms persist! The bottom rad hose stays stone cold, in fact sometimes it feels like theres only air in it when I squeeze, but cold water come out of the lower bleed screw.
The top hose to radiator gets red hot. Hoses to and from matrix are hot enough. Heaters in car blowing good and hot.
There just seems to be an endless amount of air to bleed out. No matter how long I work at it (literally hours) there is always more air to come.

I guess that about covers it. My initial thoughts were duff thermostat not allowing coolant to cycle, but that doesn't seem to be the case. Perhaps a blocked rad: so I cleaned it, flushed it, bled it still no heat in bottom of rad, too hot at top hose.

Any help/advice based on what I've already described and tried is welcome. Comments from those who have overcome this problem are what I'm looking for.
Thanks

You appear to have checked everything carefully. Replacement of the thermostat was a wise move as was pre testing the replacement. You are also confident of the coolant tank [bottle] and its cap. Logic would tell me that the only item left to investigate further is the radiator. The cleaning products can do a good job. However, as you have described there appears to be insufficient coolant [if any] exiting the radiator to open the thermostat allowing coolant to circulate as expected. You have noted that the coolant appears to boil and exit out of the coolant bottle cap. I find that continual need to bleed the system troubling in that where is the 'air' coming from?

My thinking would be to have a professional check the radiator. It may need to come out to be throughly checked and may even need to be replaced. Radiators can clog up if the cooling system has lived with poor or no maintenance. Coolant breaks down over time [ it has a lifespan] and electro chemical processes can leave deposits building up inside the radiator's aluminium core.

Yes you may well be able to flush water in the bottom and out the top and vice verse but that only shows that liquid can pass through and not how effective it is at cooling that liquid.

More investigation required.

I had some similar problems a while back, see this post.

It seemed to be a combination of several issues, when I changed the cap an refilled with coolant plus a new inlet gasket, the car never had issues again.

Head gasket. It takes a lot to get the bottom hose hot. That's the radiator working correctly. If it's blowing the water out just as it gets up to temp and not boiling. I'd be looking in that depressing yet well known direction

Diesel Do said:

Head gasket. It takes a lot to get the bottom hose hot. That's the radiator working correctly. If it's blowing the water out just as it gets up to temp and not boiling. I'd be looking in that depressing yet well known direction

Click to expand...

This ^^^^
As DD said. The bottom hose being cold simply shows that the rad is working. The rad fitted to the 1.8 is also fitted to the V6. The V6 requires twice the cooling capacity of the 1.8. The V6 bottom hose temperature is only ever around 10°C above ambient.
If you aren't able to bleed the coolant, it's likely combustion products are getting in there.

I would still buy a new cap and test that, it's only a few £. If the system is not pressurized correctly the boiling point of the coolant drops, which could mean the system does not get hot enough for the thermostat to fully open and still boils because of the lack of pressure. Anyone know at wich temperature the PRT opens fully? I kept an eye on the coolant temperature via a WiFi OBD dongle and an app on my phone, it always kept boiling when the temp hit 100 degrees, naturally.

Because of a leak in the inlet gasket, also a well known problem, I kept topping up with water until I could change the gasket itself, water has a lower boiling point than coolant, naturally, this combined with a faulty cap and the car not reaching the correct temperature for the thermostat to open fully (my theory at least), caused the car to overheat.

I might add that the aux belt snapped and caused the timing belt to skip a tooth or three a while later, all the gaskets, pump, etc. was changed, the HG was in deed alright, no sign og HGF what so ever.

It's only a few pounds, worth a shot.

However, you are saying there are lots of air in the system, which could very well be a symptom of HGF, as other have mentioned, exhaust gasses beeing forced into the coolant system. That was what everyone kept telling me was the cause of my problems.. Any other signs of HGF? Does the car loose coolant over night? Could there be a leak somewhere?

If you just cannot get the air out it has to be getting in somewhere. They're relatively easy to bleed. Sniff the expansion bottle to see if it smells of exhaust gas.

Hi. Thanks for the replies. Your thinking along the same lines as me. Namely, why is there so much air, where is it coming from, which does lead toward the head gasket/ combustion gases conclusion, but people do jump to that conclusion too hastily as many will agree, a faulty cap or cheap inlet gasket can cause these symptoms.
I would just like to explore all the cheaper fixes before diving into my wallet for a new Head gasket.
I bet no end of garages have changed head gaskets that didn't need changing these engines are so notorious for HGF. Easy money for them!
I will get a new cap for the expansion bottle, what you said about the system not pressuring correctly causing the boiling point to be lower makes good sense.
It looks like the best way to test for HGF at home is a block testing kit/ sniffer test, its just a shame they cost on eBay about as much as a complete ML Head gasket kit. But I guess once I've bought it I've got it to use again in the future - no 1.8 Freebie owner should be without one

Fr33LandER said:

Hi. Thanks for the replies. Your thinking along the same lines as me. Namely, why is there so much air, where is it coming from, which does lead toward the head gasket/ combustion gases conclusion, but people do jump to that conclusion too hastily as many will agree, a faulty cap or cheap inlet gasket can cause these symptoms.
I would just like to explore all the cheaper fixes before diving into my wallet for a new Head gasket.
I bet no end of garages have changed head gaskets that didn't need changing these engines are so notorious for HGF. Easy money for them!
I will get a new cap for the expansion bottle, what you said about the system not pressuring correctly causing the boiling point to be lower makes good sense.
It looks like the best way to test for HGF at home is a block testing kit/ sniffer test, its just a shame they cost on eBay about as much as a complete ML Head gasket kit. But I guess once I've bought it I've got it to use again in the future - no 1.8 Freebie owner should be without one

Click to expand...

I bought a sniffer kit off EBay last week for just over £15, not used it yet but will do later in the week.

If it was manifold gasket you'd have a leak! Cap fault will lower the boiling point. But won't explain loads of air being in the system. Is it actually boiling or is it just chucking the water out?

You havnt said if you have the later revised expansion tank and cap or if the revised thermostat relocation kit has beenused?

Yeah. Tricky one to answer that. I haven't taken a temp reading, it gets hot enough for the fans to kick in at the same time as the boiling happens. But it only does this after a while of driving the car, at idle/revving the motor it doesn't boil at all. I'd have to drive it till it boils, then jump out and take a reading with a thermometer.
In answer to some of the earlier points, the car doesn't lose coolant overnight and no leaking. New inlet manifold was fitted a couple of months back for that reason.
Thermostat is in the original location, behind the block, would like to fit the relocation kit soon.
I didn't know there was a revised expansion tank, Im sure I have the standard type tank.

Old stat type shouldn't make any difference to the actual running it just makes hgf more likely. If it's boiling you can normally hear it, bit like a kettle, plus it'll carry on for a bit when you turn it off. If it's gas forcing it out it won't sound like a kettle and it's stop doing it as soon as you turn it off more or less.

Diesel Do said:

Head gasket. It takes a lot to get the bottom hose hot. That's the radiator working correctly. If it's blowing the water out just as it gets up to temp and not boiling. I'd be looking in that depressing yet well known direction

Click to expand...

hi can you help with this
Hi, Having read the post below, and seeing the V6 logo, I guess you have one.
I have a freelander 2.5 V6I on a 51 plate, with what seems to be the same issues as below.
A couple of weeks ago, while doing the normal oil and water check, I noticed it was low on oil, and had no water. I topped up the oil and filled up with water and now have problems with the water side of things.
1. temp gauge stays at normal all day long, but now on tick over seems to (after about an hour) bubble in the expansion tank as if one of the gaskets has gone.
2. on checking over cooling system feel that I have bled the air out but still have bubbles in tank. But checking today noticed heat in the top end of the rad but bottom end of rad was cold.
Looking on this forum and good old google, pointing towards radiator or stat, or are these a false indication and it is the head that has gone??
In driving, it will go all day with temp at normal.....Please can you help or advise me as to where I go from here

Nina27 said:

hi can you help with this
Hi, Having read the post below, and seeing the V6 logo, I guess you have one.
I have a freelander 2.5 V6I on a 51 plate, with what seems to be the same issues as below.
A couple of weeks ago, while doing the normal oil and water check, I noticed it was low on oil, and had no water. I topped up the oil and filled up with water and now have problems with the water side of things.
1. temp gauge stays at normal all day long, but now on tick over seems to (after about an hour) bubble in the expansion tank as if one of the gaskets has gone.
2. on checking over cooling system feel that I have bled the air out but still have bubbles in tank. But checking today noticed heat in the top end of the rad but bottom end of rad was cold.
Looking on this forum and good old google, pointing towards radiator or stat, or are these a false indication and it is the head that has gone??
In driving, it will go all day with temp at normal.....Please can you help or advise me as to where I go from here

Click to expand...

A 'sniffer' test from any good w'shop will show if exhaust gases are present in the coolant. Bubbling only when the motor is running is a good pointer too. Bubbling / boiling coolant due to excess heat build-up will continue for a period after the motor is switched off and you will hear it too. That would point to a potential circulation issue [stat...].

Low cooling system pressure will cause the coolant to boil at a lower temp. Carefully check the coolant bottle for cracking and check the cap too.

Nina27 said:

hi can you help with this
Hi, Having read the post below, and seeing the V6 logo, I guess you have one.
I have a freelander 2.5 V6I on a 51 plate, with what seems to be the same issues as below.
A couple of weeks ago, while doing the normal oil and water check, I noticed it was low on oil, and had no water. I topped up the oil and filled up with water and now have problems with the water side of things.
1. temp gauge stays at normal all day long, but now on tick over seems to (after about an hour) bubble in the expansion tank as if one of the gaskets has gone.
2. on checking over cooling system feel that I have bled the air out but still have bubbles in tank. But checking today noticed heat in the top end of the rad but bottom end of rad was cold.
Looking on this forum and good old google, pointing towards radiator or stat, or are these a false indication and it is the head that has gone??
In driving, it will go all day with temp at normal.....Please can you help or advise me as to where I go from here

Click to expand...

Hi. It sounds like you're not overheating so I doubt you have a stat problem or rad for that matter. There seems to be much confusion on how radiators work. They aren't heating a room so they aren't designed to get hot and stay hot! They're designed to transfer the heat out of the water as efficiently as they can, hence all the fins and massive surface area. The hot water goes in at the top, hot water rises so it always sits on top of the cooler water in the rad, as it travels down the rad it cools down and you get cold water coming out the bottom. It takes a lot of heat in the system to get it that hot that you have hot water coming out of the bottom. It's a common misconception that the water is pumped in the top and goes straight out the bottom. The thermostat is what regulates the engine temp, it opens to release hot water out and cold in, then it'll close again, it keeps on doing this until the system is at full operating temp, then it'll stay open. Even a prt stat works like this, it just blends hot and cold together so it doesn't thermally shock the engine. If the temp continues to rise the computer uses the fans to regulate it after that.
The fact you don't sound like you're overheating suggests that your cooling system is operating correctly. Constantly getting air into the system suggests either a leak or head gasket issues.
If the cap fails it lowers the system pressure by approx 1bar. This will lower the boiling point of the coolant to approx 100*c so the system is more likely to boil and force water out of the cap. You aren't overheating so this is unlikely to be a problem.
Nodge is the V6 expert for when it comes down to the finer details. Mines actually a 1.8, I face lifted it and the only boot trim I could find was off a V6 hence the badge. I am a mechanic with over 20 yrs experience to help ease your mind.

Diesel Do said:

Hi. It sounds like you're not overheating so I doubt you have a stat problem or rad for that matter. There seems to be much confusion on how radiators work. They aren't heating a room so they aren't designed to get hot and stay hot! They're designed to transfer the heat out of the water as efficiently as they can, hence all the fins and massive surface area. The hot water goes in at the top, hot water rises so it always sits on top of the cooler water in the rad, as it travels down the rad it cools down and you get cold water coming out the bottom. It takes a lot of heat in the system to get it that hot that you have hot water coming out of the bottom. It's a common misconception that the water is pumped in the top and goes straight out the bottom. The thermostat is what regulates the engine temp, it opens to release hot water out and cold in, then it'll close again, it keeps on doing this until the system is at full operating temp, then it'll stay open. Even a prt stat works like this, it just blends hot and cold together so it doesn't thermally shock the engine. If the temp continues to rise the computer uses the fans to regulate it after that.
The fact you don't sound like you're overheating suggests that your cooling system is operating correctly. Constantly getting air into the system suggests either a leak or head gasket issues.
If the cap fails it lowers the system pressure by approx 1bar. This will lower the boiling point of the coolant to approx 100*c so the system is more likely to boil and force water out of the cap. You aren't overheating so this is unlikely to be a problem.
Nodge is the V6 expert for when it comes down to the finer details. Mines actually a 1.8, I face lifted it and the only boot trim I could find was off a V6 hence the badge. I am a mechanic with over 20 yrs experience to help ease your mind.

Click to expand...

This^^^^
DD is spot on with his description of a radiator and how it works.
The V6 is no different to a PRT equipped 1.8. If it's not overheating and it's constantly blowing bubbles into the expansion tank, then it's pretty likely that at least one HG has failed. This is really likely if the coolant has dropped below the tank level. The V6 will not tolerate low coolant without doing in a HG or two.

Hi there
can you help I put a post on here over the problems I was havening with this v6 I still seem to have an issue with-it it still siting at nominal temp and driving ok all good then I here you say
but I have up date to fist post I have a gas test on water bottle and all good thank god lol
but still not seem right so the man that did gas test saying could have a large air lock
over to you lot how do I do this as he say not know as can only find 1 bleed vale in heater pipe on bulk head
thanks nina

Hi all. Update to the original thread:
Replaced expansion tank (which had signs of crazing around bottle neck), and a new cap, both Bearmach parts. Since replacing these parts I have driven the vehicle around without any bubbling coolant from bottle cap. -Great!
Also purchased a Block Chek sniffer testing kit. Repeated testing after various driving scenarios show no combustion gasses present! -Great!

The car is now drivable, however:

Top rad hose is still always piping hot and bottom hose stone cold.
The engine now idles lumpy, chasing revs.
This morning there seemed to be quite a bit of white exhaust steam, but may be just have been the cold foggy weather.
There does appear to still be quite a bit of air to bleed out of top air screw.
I thought I saw a hint of steam coming from top right corner if radiator (standing infront of car), but cannot identity a leak in that area.
Not yet sure if coolant levels are stable or if it is slowly loosing coolant, need more time/ test drives.

Thanks for all advice received so far, if anyone has any similar experience of these symptoms, please contribute.