Erm just to check the fins are still attached, but if when you start it from cold you can see if pump works it should be spitting out of rad tube not loads just enough to let you know water is passing through might have to wait a while tho ie let it warm up a little first but not boiling ok
 
Datatek, I'm sure the baffle should be hard enough to sustain a little light proding ? Also, I didn't do any extra force, the wire (an unfolded metallic hanger) just slid through from one side to the other.

Defender30td1, The hoses get hard but not stone hard. After a long run I can still squeeze them a little bit, about 1 or 2cm, I'd guess.

Tomorrow I'll try taking the bleeder tube out and check if there's some coolant flowing, upon cold startup. Either way, I'm thinking about removing this rad and getting a new one so I'll end up checking the water pump and thermostat too.

Since I have the water pump with the metal vanes, what can go wrong with it, apart from bearing failure (of which I see no signs) ?

It's plastic, if it already has a fracture it may just fall over like a hinge with water flow or your bit of wire.
I wouldn't bother looking elsewhere, you have found the fault.
 
Well, replaced the rad with a new one. Checked the presence of the baffle with a small stone and it didn't go through. Checked the temperature on the water intake, exit and at the bottom of the rad and it all looks good.

Unfortunately it is still overheating on big inclines and it seems to be getting hotter quicker. On the incline that I've been using as a test, this time I couldn't even make it to the gas station on the top :( Engine temperature was reading 124ºC (!!!) and the gauge was in the red with the red light on. After letting it cool down and reaching the gas station I drove it there for a while and the temperature came back down to 85ºC and I drove back home (some 20km) without problems.
It seems that it is overheating only when it comes under severe load.
Any suggestions ?
 
So now you have a new rad, drive it normally for a few days without keep pushing it to max,see if your losing water,looking for steam or water in oil , if no droping of water could be fan again of stat not working properly if still no good, do you know history has someone put something like k seal in to mask something and water ways are blocked reduced because of the gunk stuff??
 
Hello I dont wish to be the bearer of bad news but I had exactly the same symtoms as you are having, perfect normally but boiling when climbing mine turned out to be warped head had it skimmed now perfect
 
Well, replaced the rad with a new one. Checked the presence of the baffle with a small stone and it didn't go through. Checked the temperature on the water intake, exit and at the bottom of the rad and it all looks good.

Unfortunately it is still overheating on big inclines and it seems to be getting hotter quicker. On the incline that I've been using as a test, this time I couldn't even make it to the gas station on the top :( Engine temperature was reading 124ºC (!!!) and the gauge was in the red with the red light on. After letting it cool down and reaching the gas station I drove it there for a while and the temperature came back down to 85ºC and I drove back home (some 20km) without problems.
It seems that it is overheating only when it comes under severe load.
Any suggestions ?

Do the aircon fans mod to give extra cooling and see if that fixes it.
 
Talked to my mechanic, who did the HG job, and he reckons it could be an airlock problem. Told me to disconnect the small hose from the rad and keep filling it until the water runs freely and without air bubbles. When I filled the radiator I did it exactly as RAVE states (just double checked) but will try this. Does anyone else feel this could be an airlock problem ?

One other thing that I forgot to post, but that I remembered as I was talking to the mechanic, is that while refilling, it looked like the coolant in the expansion bottle was becoming emulsified... the coolant is greenish/clear but I noticed that it was turning white/opaque, maybe like there were many miniscule air bubbles in it.

Def300, I've drove this RR for some 20.000km and it was fine until it started overheating sporadically and then the HG went. After having it back it as constantly been loosing coolant and is now overheating, but I never used any of those products with it.

Data, I have the fans already hooked and it's just a question of connecting a cable to make them come on so I'll try your suggestion too.
 
Talked to my mechanic, who did the HG job, and he reckons it could be an airlock problem. Told me to disconnect the small hose from the rad and keep filling it until the water runs freely and without air bubbles. When I filled the radiator I did it exactly as RAVE states (just double checked) but will try this. Does anyone else feel this could be an airlock problem ?

One other thing that I forgot to post, but that I remembered as I was talking to the mechanic, is that while refilling, it looked like the coolant in the expansion bottle was becoming emulsified... the coolant is greenish/clear but I noticed that it was turning white/opaque, maybe like there were many miniscule air bubbles in it.

Def300, I've drove this RR for some 20.000km and it was fine until it started overheating sporadically and then the HG went. After having it back it as constantly been loosing coolant and is now overheating, but I never used any of those products with it.

Data, I have the fans already hooked and it's just a question of connecting a cable to make them come on so I'll try your suggestion too.
We have told you take pipe of rad to bleed,are sure its not just water that you put in and its mixing with your anti freeze ie Diluting it. if it were me I would remove stat and run to be sure,check water pump flow,check and make sure heater matrix isn't blocked and all hoses if no luck pressure test when hot and when cold that's all you can do ..
 
If it were a cracked block what would the symptoms be,a header tank full at the start of a jorney once hot , water Escaping water in header tank lowering but not boiling until it has no more water supply, head gasket water loss through cylinders = steam or into oil ways oil in sump or showing in header tank ,oil mixing with water evident via header tank,or combustion Pressurising the water system pushing water out of header tank leading to over heating its got to be one what are your symptoms ????
 
The symptons started as water escaping from the expansion tank after climbing big hills. Now the symptons are water escaping and overheating, when climbing big hills.
 
The symptons started as water escaping from the expansion tank after climbing big hills. Now the symptons are water escaping and overheating, when climbing big hills.

If it's had a HGF, I would bet the problem is the head.
 
Escaping from header tank or elsewhere , when you drive for a while And park up you should be able to unscrew header cap whilst engine is running, I Tried it today after 10 mile jorney no water pressurised enough to come over the top , bit like opening a coke bottle just a bit of pressurised air , if it spouts out you got to much pressure = hgf
 
Escaping from header tank or elsewhere , when you drive for a while And park up you should be able to unscrew header cap whilst engine is running, I Tried it today after 10 mile jorney no water pressurised enough to come over the top , bit like opening a coke bottle just a bit of pressurised air , if it spouts out you got to much pressure = hgf


That is a very risky suggestion, if the water is up to full temperature it will instantly boil when the pressure is released.:eek:
 
That is a very risky suggestion, if the water is up to full temperature it will instantly boil when the pressure is released.:eek:

I did say a 10 mile journey and yes if it's in good condition it won't boil over but, ok take care when opening cover with a rag and if it feels like it wants to blow forget it as it hgf and over pressurised .
 
I did say a 10 mile journey and yes if it's in good condition it won't boil over but, ok take care when opening cover with a rag and if it feels like it wants to blow forget it as it hgf and over pressurised .

You missed the point. The reason the cooling system is pressurised is that it raises the boiling point of the coolant. In a normal situation, with the engine at working temperature, the coolant will boil when the pressure is released which can be extremely unpleasant and it will prove nothing. Ten miles should be more than enough for the engine to be at normal working temperature, mine gets there in less than 5 kilometers.
 
You missed the point. The reason the cooling system is pressurised is that it raises the boiling point of the coolant. In a normal situation, with the engine at working temperature, the coolant will boil when the pressure is released which can be extremely unpleasant and it will prove nothing. Ten miles should be more than enough for the engine to be at normal working temperature, mine gets there in less than 5 kilometers.

Datatek I have a dse and a pegeout 1.9 a I can do a motor way run pull over leave it for a minute or so with engine running, this keeps the water circulating remove the cap carefully and the water just sits there so I haven't a clue what your on about where as if I turn the engine off and try it the chances are it will push its self out of the rad or header tank what ever is fitted to what particular car , but if the head gasket were to be leaking causing a ( over Pressurised ) system this would be a different case when opening the cap the water would ooze out due to the extra pressure build up .
 
Datatek I have a dse and a pegeout 1.9 a I can do a motor way run pull over leave it for a minute or so with engine running, this keeps the water circulating remove the cap carefully and the water just sits there so I haven't a clue what your on about where as if I turn the engine off and try it the chances are it will push its self out of the rad or header tank what ever is fitted to what particular car , but if the head gasket were to be leaking causing a ( over Pressurised ) system this would be a different case when opening the cap the water would ooze out due to the extra pressure build up .


Obviously the warnings in handbooks about scalding and not removing the pressure cap are wasted. Presumably your cars are over cooling.
The water doesn't ooze out either it comes out as droplets under pressure.
It's basic physics, boiling point rises with pressure.
But have it your own way, I can't be bothered to argue with you.
 
Obviously the warnings in handbooks about scalding and not removing the pressure cap are wasted. Presumably your cars are over cooling.
The water doesn't ooze out either it comes out as droplets under pressure.
It's basic physics, boiling point rises with pressure.
But have it your own way, I can't be bothered to argue with you.

Yes there are warning for thick people who think they can just uncrew the cap completely in one go , bit like a coke bottle isn't it open it quickly and your squirted on open it slowly and you remain dry , the only differance is the water in the car is hot so thick people need to know, but when realising slowly you can tell if its normal pressure or over pressure that's the differance .
 
I have found from personal experience that every single component in the cooling system needs to be working correctly otherwise the diesel will overheat. Particularly if it is chipped. There is no spare capacity.

I replaced the thermostat and water pump to start with. It improved but still ran occasionally hot. Then the radiator burst and I replaced it with new OEM. Again an improvement. Final piece in the jigsaw was the viscous fan. Overheating is now a thing of the past since I did it. Yes I have done the aircon fan mod but it is not as good as the viscous fan.

A useful tool for investigating problems I have found is a cooling system pressure tester. The pump bit is relatively inexpensive but a BMW adapter is needed and they are pricey.
If you pressurise it and leave it overnight and it doesn't hold pressure it would point towards the head gasket and/or cracked head.
 
Well, I'm going to bleed the rad again as per my mechanics instructions (small hose off and keep filling it until I get a constant stream of water from the nipple). Then I'll hook up the AC fans so that they will be always running, independent of temperature. If that still doesn't fix it, I'll try replacing the fan with a new one. If that doesn't fix it I'll declare the head cracked and move on to replace it.
 

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