Ok long story short, car severely overheated, so much so after opening the oil cap there was smoke coming out from there as well, the pipe from radiator going to the trans thermostat came off. Most probably because I was fiddling with the trans cooler pipes earlier and probably didn't snap one in correctly Its been a week since and I'm still not sure if the head gasket is gone or now.

There is no sniffer test available so I have to go on my own diagnosis. Car does not overheat, thermostat is not an issue, since I don't have one for the past one year, fan, rad etc etc but seems to me the system is getting over-pressurized but holds the pressure for more than a day, as in if I let it cool down overnight and then the next day there is still pressure in the system as its hisses when I open the cap. No oil in the coolant but can smell some new smell in the expansion tank every time I open it.

Maybe I'm not bleeding the system right although I've had Land Rovers and Range Rovers for 10 plus years now and never had an airlock issue, and am following the official procedure of refilling as mentioned in Rave. I did see coolant seeping out of the expansion tank when at temp and hose pipes hard but I am thinking that could be because I overfilled the tank.

I can hear and see bubbles along with coolant when engine switched off after a drive and I loosen the bleed screw, and takes a while for only a steady stream of coolant. But I can let the car idle all day without the cap on and not see any bubbling in the coolant tank.

Temp doesn't go over 100C but pipes are rock hard or at least I think they are and I don't drive it for too long fearing it might blow a hose or something. But it drives just fine temp needle stays in the middle and the secret menu as well as the icarsoft ( no codes btw ) always show temp below or close to 100C

So no overheating, no steam from exhaust, no oil in coolant, holds pressure overnight just over pressurized ( or what i think is over pressurized )

I read in one of the posts while searching that it has taken some people a couple of days to get rid of all air the system, drive a few miles, the bleed the air from the screw, repeat this over a couple of days, maybe thats what I need to do to?

This is literally driving me crazy, maybe I'm just spooked and over reacting or there really is an issue, I just don't know and worse of all I just moved into the middle of nowhere so there is no help close by.

Any insight into this would be greatly appreciated.

Thanks

Last edited by desertdude on 25th Mar 2018 9:08pm. Edited 2 times in total

There is a thread somewhere and also a website that discusses the potential problems with bleeding the BMW M62 engine and confusing the symptoms with head gasket failure.
The top hose blew off of mine and especially after fitting the 80 degree stat mod I had quite a lot of trouble bleeding mine and even now the top hose is hard.
The header cap on mine is a 140 I think but check what colour you have and I bled mine better after raising the front of the car on a couple of sleepers and squeezing or burping the pipe coming from the bottom of the rad to the stat housing with the engine running and cap off.
The auxiliary water pump bolted to the inner wing should also be running but mine doesn’t .
Have a look at the meeknet site regarding the bleeding procedure.

If you still have the original spec thermostat fitted, then the hoses will be rock hard due to the pressure in the system once fully up to temp, this is normal. It's also entirely possible for the system to hold at least some of that pressure overnight, hence the hiss, again normal. Also, having overheated, it will smell disgusting!! They smell pretty awful running with the OE spec 'stat in any case. Also, have you changed the oil and filter since the overheat? I would do this as a matter of course following such an event. Drives:
2010 FFRR TdV8 Vogue - Stornoway Grey
2010 FFRR TdV8 Vogue SE - Zermatt Silver
1998 BMW E36 M3 GTII

Unnecessary quote removed

Thanks, I'll see if I can find that thread and website

rvbush wrote:

If you still have the original spec thermostat fitted, then the hoses will be rock hard due to the pressure in the system once fully up to temp, this is normal. It's also entirely possible for the system to hold at least some of that pressure overnight, hence the hiss, again normal. Also, having overheated, it will smell disgusting!! They smell pretty awful running with the OE spec 'stat in any case. Also, have you changed the oil and filter since the overheat? I would do this as a matter of course following such an event.

...relevant? BMW 8 series though

http://www.meeknet.co.uk/e31/E31_Cooling_S...eeding.htm

Thanks Martin but I found it earlier on the same site about a 7 series and that's a bit more relevant as ty systems are more similar. But thanks regardless for taking the time to look it up and post it.

If you fill the coolant to just below the level of the cap and squeeze the pipe running from the bottom of the rad to the stat on the left as you look at it you will probably get air bubbles out the cap, just keep doing this and then run the engine and do it some more, have the front raised up, until the air stops bubbling out when you squeeze the pipe but try not to chop your fingers off in the process! remove excess coolant via the normal bleed screw
If you can get a sniff test done that would also tell you if any exhaust gas is going into your coolant.
Make sure your heater is on max heat as well and the one in the centre of the dash when bleeding

Heater is a no go as this winter or what we call winter here I found out its been bypassed. Probably a leaking heater matrix, and about 99% of all cars that have any heater issues get them bypassed as the heater never gets used. We are more concerned about our air conditioners here.

Well just to concluded this thread ( for now ) fingers crossed. I took a chance and got a used but know good original Beher radiator from a local LR indy, Too out mine, it was pattern part no name unknown brand one and there were signs of leaks in the usual corners and seams but on the condensor side, the engine fan side was flawless, with not even a single bent fin, all new and shiny, thats why I never suspected the rad. Having inspected it plenty of times with the fan and shroud off.

Well all seems to be good for now, normal hose pressure, drove around in 32-35 C heat for around 20 minutes and the temp never went past 84C and now I can even hear the Viscous fan kick in around 80C + never heard the fan before other than a cold start for less than a minute.

Side Note : The OEM rad seemed to be made of tin foil I can literally lift it with 2 fingers, while the Beher one is I would say at the very least 4 times as heavy, so the difference in quality is obvious. I know its quite expensive compared to the pattern part rad but you get what you pay for. I think if you can afford it, better go for the original and IMO a good used one is better than the new pattern part one.

Anyways fingers crossed, hopefully this will be the end of an almost month long saga.

P.S : Before I overheated, which lead to this entire mess in the first place, I had used Gunk's radiator flush twice, maybe that ate away the thin rad and made it leak ? Thoughts ?

Spoke too, soon. I think it is a head gasket. Went on an extended test drive, gave it a good run. Temp stayed stable but when slow down to a crawl or stop after that, the temp keeps slowly rising. And system once again filled with air, ane coolant leaking from the cap. So much air that top couple of lines of the radiator are ice cold.

First I thought I didnt bleed it properly, because loosening the bleed screw let out a lot of air and the system gurgled and the entire radiator and bottom hose also warmed up.

Waited for an hour, refilled coolant, went for a test drive again and now exactly the same. Top hose hot and rock solid. Top of radiator and bottom hose cold and coolant flowing like a stream from the rad cap.

This time I didnt bleed it, waiting to see if it holds pressure overnight.

Did you bleed it with the front raised and burping the pipes ?

Yes

I will give bleeding it another try tomorrow morning, hopefully its air in the system, but chances dont seem good.

I think you are right , can you perform a compression test and or leak down test which should tell you, you could check all your plugs to see if any of them seem a different colour?
A sniff test would be easiest if you can get the kit and a coolant system pressure check maybe.