Hippo is overheating......AGAIN!

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I've had budget thermostats fail within minutes of the engine reaching running temperature.
For this reason, I will now only fit a genuine LR part.

You can test the fan control unit by simply putting the AC on. The AC system tells the engine ECU that AC is running. The engine ECU then sends a PWM control signal to the fan control unit. The fan control unit then alters the fans speed based on what the engine ECU is telling it to do. So the system is easily checked ;)
 
I'm ready to commit murder! Murder of the finicky Hippo that is.

So,.....since the holiday is over (all the family is gone, thank God!), I rolled up my sleeves yesterday, and decided to dig into this thing (wife been pestering me to fix it, doesn't like to drive the Benz). So I started with the electrical (fuses, relays, OBD codes,...the works). It gave me 1471, 1472, 1477 and I know what they mean. I checked the motors (all good), all good with relays and fuses for the fans (has two, V6),.....all good. Coolant missing from the bottle,.....topped it off, and for the FS, I looked at the bottle cap (seems normal, but I don't have the way to test it for pressure, and too lazy to drive down into city). So it happens I had an old cap from my L322 on the shelf, I dusted it off, and put that one on.

Fired the thing up, turned on the A/C, and waited for it to overheat. I waited for about an hour! Then I got ****ed off, and drove it on the ranch in circles (about a mile and 1/4 round driveway). I couldn't get it to overheat! Then I drove it into the hills (on the trails behind the ranch), up and down, through the gullies, over the stream, got it filthy dirty, and it still didn't want to overheat! WTF!?

Pulled over on the mountain, heard fans running full speed, opened the hood, squeezed the bottom rad hose (warm, but not HOT),.........all seems to be working as it should!

Drove it down the mountain to the ranch, cleared the codes with the scanner, opened the bottle of Sam Adams, and tried to figure out what the hell is going on.

Is it possible that the failed expansion bottle cap (it's new, came with the bottle about 400 miles ago) causes the lower rad hose to be stone cold, upper HOT, and fans not running? I am almost 60 years old, and I wrench on cars, bikes, and airplanes my whole life (since about 13). I've never seen the behavior like this. And I'm no stranger to British engineering either (three Jags, Range Rover, etc.).

So if someone can kindly explain to me how is the replacement cap on the bottle "fixing" all this, I'll be all ears.

And BTW,......wife drove the thing to work today, and reports "Hippo likes me again!".

WTF?
 
Hi Danielsand. I am having the EXACT same sympyoms with mine, exept mine is rhe 1.8 K-series petrol motor. Started with coolant bubbling out of the expansion cap, bottom rad hose stone cold, top hose melting hot! Like you I suspected thermostat failure, so I replaced that, the water pump was brand new back in May this year and had decent heat from heater matrix so pump ruled out. The car would idle for hours on the driveway without overheating, this only happened when I took it for a long run. Also, the bottom rad hose stayed cold and there seemed to be an endless amount of air to bleed out of the bleed screw, no matter how well I bled it there was always more air in there - Was this something you encountered?
I researched the net and read up on expansion bottle/cap failure which described symptoms like ours so this was my next job, bought a brand new bottle and cap. This seems to have partially solved the problem, I've driven It around for a couple of days with no bubbling coolant, but it doesn't seem quite right. It's running a little lumpy at idle, chasing revs. I was wondering perhaps partial head gasket failure, water getting into one of the bores? I tested the coolant with a block chek sniffer test kit, no combustion gasse present in coolant. No coolant in the oil, or oil/mayonnaise in coolant.
I don't know anything about the V6 engine (exept we share the same radiator), not sure how much you know of the Rover K series 1.8, what i'm wondering is what whould cause both types of engine to suffer same symptoms.
 
It was good while it lasted. After replacing thermostat, pipes, and the expansion tank, wife didn't have any issues with Hippo for few months. And over the weekend, she barely made it home.

Expansion tank is getting over pressurized, fluid boiling, and steaming. Fans are not coming on. It didn't overheat (didn't let it run when we noticed the problem), and it was brought home on the flatbed.

So what am I looking to replace now? Waterpump? There is no oil in the coolant, and no coolant in the oil (HGF higly unlikely). IF waterpump took a dump, why are fans not coming on? Went from running perfectly on Saturday, to this yesterday.

Imputs/experiences are very welcome!:confused:
being a fender owner ours dont have as many issues as yours but being helpful and knowing all the rover engines i suggest you ask at the rover 75 and mgzt club.co.uk,there are more people on there with experiance of the kv6 than here and may have a better idea
 
The KV6 engine runs hot by design. If you look at the live OBD2 data, you will see that. Here in the UK, it's not uncommon to see the coolant at 100°C cruising. If you are in traffic or the day is warm here (25°C) the coolant will be over 100°C.
Obviously these high running temps require a well sealed cooling system. The pressure cap needs to be able to hold the pressure this over boiling point cooling system runs at.
I noticed that you have drilled the thermostat. This can have an adverse effect on the way the engine gets to running temperature. Basically if you bleed cold water over the thermostat, it makes it open slower. This means that the engine will need to get hotter than normal before the stat opens. Obviously this higher initial temperature will pressurise the coolant, for which the cap must be able to hold.
 
Hi Danielsand. I am having the EXACT same sympyoms with mine, exept mine is rhe 1.8 K-series petrol motor. Started with coolant bubbling out of the expansion cap, bottom rad hose stone cold, top hose melting hot! Like you I suspected thermostat failure, so I replaced that, the water pump was brand new back in May this year and had decent heat from heater matrix so pump ruled out. The car would idle for hours on the driveway without overheating, this only happened when I took it for a long run. Also, the bottom rad hose stayed cold and there seemed to be an endless amount of air to bleed out of the bleed screw, no matter how well I bled it there was always more air in there - Was this something you encountered?
I researched the net and read up on expansion bottle/cap failure which described symptoms like ours so this was my next job, bought a brand new bottle and cap. This seems to have partially solved the problem, I've driven It around for a couple of days with no bubbling coolant, but it doesn't seem quite right. It's running a little lumpy at idle, chasing revs. I was wondering perhaps partial head gasket failure, water getting into one of the bores? I tested the coolant with a block chek sniffer test kit, no combustion gasse present in coolant. No coolant in the oil, or oil/mayonnaise in coolant.
I don't know anything about the V6 engine (exept we share the same radiator), not sure how much you know of the Rover K series 1.8, what i'm wondering is what whould cause both types of engine to suffer same symptoms.

If the cap/pump/stat are ruled out, I would say the only thing left would be the variable valve motors. I also replaced those (few months back when I got 1471/1472 for the first time), and didn't see any improvements.

When I replaced thermostat, I had a chance to look at ALL wiring, and I didn't like what I saw. Basically,......I would need to replace all wiring in the engine compartment to "feel safe". Wires are brittle, easily cracked, patched up with tape in many places,.....a mess.

Unfortunately, I am not familiar with 1.8L but I would think they are the same. Engineered by same people, with same materials.

Totally cute (and capable) little cars, but VERY finicky. I'm keeping my fingers crossed, and keeping it on the road. Wife works down in the city (10miles round trip, five days a week), and for that kind of driving, this thing will do. We are luckier than most people, and we have six vehicles in the garage, so no chance of being stranded. The way Hippo is acting, I will never feel secure enough to take it on the long trip.
 
being a fender owner ours dont have as many issues as yours but being helpful and knowing all the rover engines i suggest you ask at the rover 75 and mgzt club.co.uk,there are more people on there with experiance of the kv6 than here and may have a better idea

Appreciated. I'll check that out. I would like to sort this thing to the point of hopping in it, and drive it 2000 miles one way. Not sure that will ever be possible (probably was when the thing was new, and under warranty).
 
The KV6 engine runs hot by design. If you look at the live OBD2 data, you will see that. Here in the UK, it's not uncommon to see the coolant at 100°C cruising. If you are in traffic or the day is warm here (25°C) the coolant will be over 100°C.
Obviously these high running temps require a well sealed cooling system. The pressure cap needs to be able to hold the pressure this over boiling point cooling system runs at.
I noticed that you have drilled the thermostat. This can have an adverse effect on the way the engine gets to running temperature. Basically if you bleed cold water over the thermostat, it makes it open slower. This means that the engine will need to get hotter than normal before the stat opens. Obviously this higher initial temperature will pressurise the coolant, for which the cap must be able to hold.

This makes perfect sense! But why is KV6 designed to run hot? What's the benefit? What would happen if the thermostat is taken out of the loop?

AFAIK, thermostat is the ONLY mechanical device that allows (or denies) the circulation of the coolant through the lower part of the rad, and the engine. If it's out, coolant will take a LONG time to warm up, engine will run rich (wasting fuel, and polluting, until it reaches operating temp), but the engine will never overheat. So why "playing" at the top of the charts (when it comes to temps), why not have the thermostat open sooner, keep the engine temps/pressures lower?

Many moons ago I was in a Volvo on a cross country trip. Somewhere in Colorado (climbing up to the Eagles Pass) Volvo overheated. I pulled over, let it cool down, yanked the thermostat out, threw it in the ditch, and drove all the way to Cali without a single issue. Why is this not possible here? Is VIS the reason? And why do we "need" VIS to begin with? Pollution again? Tree hugers demanding it because of "global warming"?
 
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being a fender owner ours dont have as many issues as yours but being helpful and knowing all the rover engines i suggest you ask at the rover 75 and mgzt club.co.uk,there are more people on there with experiance of the kv6 than here and may have a better idea

I just read a TON of useful info on that forum you suggested. Thank you. Didn't join yet (I might), but now I'm certain I need a new upper intake manifold (along with VIS motors), for I believe my 1471/72 codes are coming and going because of that (there is also rattle when cold, and the general lack of power).

The problem is,......new ones are over a $1000, and the used ones less than half of that (but no guarantees that they are good to go). Crap.
 
This makes perfect sense! But why is KV6 designed to run hot? What's the benefit? What would happen if the thermostat is taken out of the loop?

AFAIK, thermostat is the ONLY mechanical device that allows (or denies) the circulation of the coolant through the lower part of the rad, and the engine. If it's out, coolant will take a LONG time to warm up, engine will run rich (wasting fuel, and polluting, until it reaches operating temp), but the engine will never overheat. So why "playing" at the top of the charts (when it comes to temps), why not have the thermostat open sooner, keep the engine temps/pressures lower?

Many moons ago I was in a Volvo on a cross country trip. Somewhere in Colorado (climbing up to the Eagles Pass) Volvo overheated. I pulled over, let it cool down, yanked the thermostat out, threw it in the ditch, and drove all the way to Cali without a single issue. Why is this not possible here? Is VIS the reason? And why do we "need" VIS to begin with? Pollution again? Tree hugers demanding it because of "global warming"?

Gee lots of questions.
The high running temperature is purely to aid economy and so lower emissions. If the running temperature was 85°C lots of K series problems would disappear. Emissions would be slightly higher though.
In theory you can remove the thermostat valve and run the engine like that. This wouldn't be advisable here in the UK but California is less of an issue. The engine ECU will always try to ensure that the mixture is correct. However this is only completely true at an engine temp of over 75° C or so. Below that temperature the engine runs in open loop control. This means it doesn't monitor the exhaust gases. This could shorten the life of the cats as the engine might run a little bit rich for longer periods. Other than that, I can't see any other problems arising. The VIS system simply alters induction length at different engine speeds. This helps with engine torque output. It has little effect on emissions, per se. However a higher torque will help fuel economy and so lower emissions as a byproduct.
 
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Gee lots of questions.
The high running temperature is purely to aid economy and so lower emissions. If the running temperature was 85°C lots of K series problems would disappear. Emissions would be slightly higher though.
In theory you can remove the thermostat valve and run the engine like that. This wouldn't be advisable here in the UK but California is less of an issue. The engine ECU will always try to ensure that the mixture is correct. However this is only completely true at an engine temp of over 75° C or so. Below that temperature the engine runs in open loop control. This means it doesn't monitor the exhaust gases. This could shorten the life of the cats as the engine might run a little bit rich for longer periods. Other than that, I can't see any other problems arising. The VIS system simply alters induction length at different engine speeds. This helps it's torque output. It has little effect on emissions, per se. However a higher torque will help fuel economy and so lower emissions as a byproduct.

Sorry about so many questions. ;)

Just brainstorming on the open forum. You confirmed my thinking nevertheless. And another question..........:D.......since so many people all over the world report Hippos overheating (and all other problems associated with this, to the point of complete engine failure), how come nobody offered thermostats with different temperature ratings? Since I came to LRs from a long line of Jeeps, I know we can choose three different temperature ratings for the Jeeps, and those stats are available in every neighborhood auto parts store.

I did not know that 75C (or so) is when ECU starts leaning the mixture, and all is good as far as emissions. In that case, a 80C (or so) thermostat would be nice to have. My MBZ (S430) has a so called "smog pump" which is basically a fan that blows outside air into the intake, for the first 60 seconds after start (aids in combustion, and reduces emissions until the cats warm up). That car you can't overheat even if you try. System is not flawless though, and carbon build up in the schrader valves and intake manifold has been well documented. Once the air passages in the manifold get plugged up, the smog pump fails (easy to replace, and the schraders are easy enough to keep clean).

Anyway,......went off the path a little here. Since this IS SoCal, and since we see 32F (0C) air temp once every couple of years for an hour or so in the early morning, I think I'll "experiment" with Hippo when this cheapo thermostat gives up. I'll take it out, and see what happens with the operating temperatures. I am not worried about the emissions inspection (every two years), and running it hot before the inspection is a MUST anyway. I have 22 months before my next inspection, and by that time I think I'll replace the engine.

I am also looking for an add on temp gauge, that I can install in the dash. The Jags I had in the past had the same type of temp gauge (it stayed in the middle until it was too late!), and there is a guy on the Jag forum that designed (and produced) a "real gauge" (that's what he calls it) that installs in the cluster instead of the "idiot gauge". I need to see with him what can be done for Hippo.

There are two reasons (actually three) why I'm so involved with this vehicle. First,....for some unexplained reason my wife is in love with it (and I'm in love with her!). Second,....at the time of purchase I was looking for the replacement engine, and one of my former colleagues in the car business (service manager/part owner of a major dealership) scolded me! He said he couldn't believe that I of all people would buy this "British Dud". Continued on saying how bad these are, how they are good for about 80K miles, and then off to junk yard. Jokingly called me a cheap bastard, and suggested I go and buy a brand new whatever. The third reason is that I'm bored, and a little OCD.

So I am determined to keep wrenching on it, until I see well beyond 200K on the odometer, and prove him wrong. :D
 
Thermostat wise. There is a better unit available that can take a few different temperature stats. These are supplied by a guy called Keiser, based in South Africa. I had one installed in my hotted up ZS180. That engine ran a 90°C. It was 100% reliable for the 80K miles I did in it. This was even more impressive as my ZS180 made 225 BHP.
The KV6 can do huge mileages if it's looked after. The bottom end is very durable. The head gasket joint and liners are the weakest points on the whole engine.
 
Oh yes. The Freelander's temperature gauge shows normal from 75° C to 114° C. This prevents the masses panicking should the guage fluctuate.
 
Oh yes. The Freelander's temperature gauge shows normal from 75° C to 114° C. This prevents the masses panicking should the guage fluctuate.


I know (from your earlier posts). I've read everything ever written on the subject by you, Hippo, and few others. I know about Keiser too. Maybe find him, and buy it for spare (to have on hand when this one goes).

These cars have very BAD reputation over here. Most Americans barely know how to pump gas in their vehicles, especially women (to whom these were marketed). And most people have a good reason for it,......they live WAY beyond their means (on credit, and paycheck to paycheck), so they don't have time to "work on cars", in this rat race.

I grew up in times when time was abundant, and I always liked turning the wrench. Back then, tuning the muscle cars and bikes, was a matter of "growing up manly", and geeks were ostracized. No computers, no video games, and very few "sissies" in the neighborhood.

So these were purchased (novelty), and driven to death with little, or no care. There are many around with blown engines that people can't get rid of, and they end up on the junkyard (where mine came from). As I said,....to me it's a challenge, and proving the point, and since money is no object,.......we'll see how far I can push it. Since I've spent most of my life following rules, once I was free, I started breaking them. In the county where everyone drives American trucks, I am considered an eccentric "gentleman rancher", and I drive "unreliable/expensive" British vehicles. Oh, well. ;)
 
I just read a TON of useful info on that forum you suggested. Thank you. Didn't join yet (I might), but now I'm certain I need a new upper intake manifold (along with VIS motors), for I believe my 1471/72 codes are coming and going because of that (there is also rattle when cold, and the general lack of power).

The problem is,......new ones are over a $1000, and the used ones less than half of that (but no guarantees that they are good to go). Crap.

if the vis motors are shot pm dave (stocktake)on there tell him mark sent you ,he fixes them,not sure if its the same set up though on the free lander
 
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