Discovery II TD5 coolant pressurised

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Got to bleed it properly first then if you are really losing that much you have a leak
Bleeding Landrovers
 
Hi @geoff edwards

One thing does spring to my mind from the distant past.

Have a look here,
https://www.aulro.com/afvb/discovery-2-a/212384-thermostat-fitted-reverse.html

May be worth checking it is correct.

@Alan Crossley , not sure if they are the same or not, but might be worth you checking yours as well, knowing how you have cooling issues.

Cheers
Thanks worth checking. I did replace a hose to the thermostat that split - had to be taken home by AA. So I have not interfered with it until I had another problem so changed the thermostat. I had a look a the car but couldn't take a photo unless I remove the fan. Looked at the AU post and couldn't access one photo until my membership is sanctioned - probably tomorrow. I need to print the photo and compare it to my thermostat. I'll then report back. Note the Haynes manual is no help and the photos are poor anyway.
 
Just undoing the bleed screw -without touching the expansion chamber. Very little bubbles of air escaping.

OK, I would raise it up, as said, it did take me 3 heat cycles to fully bleed my TD5. One other thing is, if the pipe with the bleed plug in ti was not replaced ( amongst the 4), then I suggest you change the screw for an anodised one . as I had one snap. whihc is why I had to bleed the system....:oops::oops:

Cheers
 
if its driving around town ok, but when under hard load like on motorway its pressurizing and chucking water out, on my experience of td5's, I think you have either failed head gasket or more likely a crack between exhaust and water jacket in the cylinder head, these cracks are hairline and under load/heat allow exhaust gas into waterway causing the problem you have, a new head would be the answer
 
if its driving around town ok, but when under hard load like on motorway its pressurizing and chucking water out, on my experience of td5's, I think you have either failed head gasket or more likely a crack between exhaust and water jacket in the cylinder head, these cracks are hairline and under load/heat allow exhaust gas into waterway causing the problem you have, a new head would be the answer
Hi johnlad. There is no evidence that would suggest that the head gasket has gone since it was replaced last June, it was sent for testing for a crack at the time. There is no oil in the coolant and no coolant in the oil, it passed a sniff test OK. As I have not got rid of the air locked in the heater yet I have not eliminated the possibility of the coolant not circulating properly. Maybe there is a leak that appears under load which I can't see. Maybe there is a dye I could put in? I have now attached a plastic bottle to check whether there is a build up of pressure leading to the pressure cap ejecting coolant. with the new cap this has happened, which suggests that the cap I bought last year is defective.
 
Hi Geoff,

You could add the UV dye to the coolant.

kits are available on the bay of flea , about a tenner ( actually now £13) for the dye and the light.

EDIT:

ebay number is:
230723938073

Cheers
 
Hi johnlad. There is no evidence that would suggest that the head gasket has gone since it was replaced last June, it was sent for testing for a crack at the time. There is no oil in the coolant and no coolant in the oil, it passed a sniff test OK. As I have not got rid of the air locked in the heater yet I have not eliminated the possibility of the coolant not circulating properly. Maybe there is a leak that appears under load which I can't see. Maybe there is a dye I could put in? I have now attached a plastic bottle to check whether there is a build up of pressure leading to the pressure cap ejecting coolant. with the new cap this has happened, which suggests that the cap I bought last year is defective.
If the leak is from exhaust ports into water jacket as is common on td5 then there won't be any oil in coolant or visa versa. Also dye won't show a crack between exhaust ports which is known to show itself under heavy load i.e. motorway
 
Thanks johnlad I hope the leak is not happening where you describe as that means that I would not be able to pay for a new cylinder head and fitting it. My motorway section of the 34 mile trip to Swindon was done at a steady 50-60mph. I am awaiting delivery of the dye and UV torch, fingers crossed the leak is elsewhere. Update: dye arrived and I ran the car on 2000 revs for 20 minutes, actually 30 minutes. No leaks but the overflow from the expansion chamber shed about half a pint of coolant. The top hose was hard but not rock hard and returned to usual pressure when the car is cold. I could take the cap off without any boiling coolant. I noted that the viscous fan could turn very freely and wondered whether it should be stiffer as the engine was very hot?
 
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Second on the cap. Is it using any water still?

If its pressurised that much it should overflow out to the open ended pipe.

I stick a bottle over it with a hole in the cap to check if the pressure is too high and water is escaping through the over pressure vent pipe.

But that will only work if the cap is working correctly.
Hi Simon098 I have fitted a plastic bottle to monitor coolant loss through expansion tank cap operating.
 
How about a soft bottom hose collapsing (under suction from water pump) and restricting the flow is this heard of anymore the original hoses on mine look very poor in quality
 
How about a soft bottom hose collapsing (under suction from water pump) and restricting the flow is this heard of anymore the original hoses on mine look very poor in quality
Both hoses going to the thermostat have been replaced. I dont know about the conditon of the other hoses beyond the two metal pipes. One of the junctions of a metal pipe with a hose has been repaired with an epoxy filler as there was a leak- the metal pipes are expensive. You mention ". . . is this heard of anymore" what does that mean, was it a known fault? My car's a Dec 1999 registration so there might be several items that may need to be replaced, which might have been already replaced.
 
:eek:16 YR Warranty:rolleyes: Don't want to p!ss on your strawberry's Geoff but had a lad down south with the same problem as you:eek: Ended up with NEW Head , After 2nd pressure test found head cracked !
 
:eek:16 YR Warranty:rolleyes: Don't want to p!ss on your strawberry's Geoff but had a lad down south with the same problem as you:eek: Ended up with NEW Head , After 2nd pressure test found head cracked !
I see no reason why a car should not last for years and years, provided its maintained properly. I accept that a manufacturer can not afford to provide a warranty for that long. Never mind about your mate having the same issues as me. I doubt it. I read plenty of stories of Land Rover owners replacing cracked heads and still finding they have a problem. To recap: overheating due to failed coolant pump, further overheating due to blocked radiator. Radiator cap replaced, prevented build up of pressure as it did expel coolant. Presently, awaiting dye to search for coolant leak. Note that it may not work if there is a crack in the cylinder head leaking coolant into the exhaust manifold. If that's the case will sell on eBay to someone who can carry out the work themselves. I can't, as I do not have a garage in which to work on the car. Might try Steel Seal, it works for some.

Got the dye test kit and the coolant system is not leaking. The engine had to be run at 2000 revs for 20 minutes. It eventually expressed about a pint of coolant into my temporary bottle which I am using to check if the cap was working. So the motor is overheating

I did notice that although the motor was working at 2000 revs the equivalent of driving a steady 50mph after I switched off I checked the fan expecting it to be stiff, but it wasn't so have I got a defective fan?
 
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Hi Simon098 I have fitted a plastic bottle to monitor coolant loss through expansion tank cap operating.[/QU
Hi @geoff edwards

One thing does spring to my mind from the distant past.

Have a look here,
https://www.aulro.com/afvb/discovery-2-a/212384-thermostat-fitted-reverse.html

May be worth checking it is correct.

@Alan Crossley , not sure if they are the same or not, but might be worth you checking yours as well, knowing how you have cooling issues.

Cheers
Hi Neilly just to confirm the thermostat is fitted the correct way.
 
I did notice that although the motor was working at 2000 revs the equivalent of driving a steady 50mph after I switched off I checked the fan expecting it to be stiff, but it wasn't so have I got a defective fan?
To check the fan try to stop it with a rolled up newspaper with engine running when the engine is hot...if you can it's fubar
 
Thanks sierrafery just what I needed to know. Update: tried the test and the fan stopped. Also tried it at 2000 revs and it stopped.
I have fitted the new one and after coming home last Wednesday I tested the fan.whilst the car was hot. I could spin the fan it was totally free to rotate. I thought that it should be stiff so as to provide the full effect of the fan on cooling.

Incidentally, I lost over 6 litres of coolant each way on the trip total 64 miles. Is this fan defective or its that how it is supposed to work?
 
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Thanks sierrafery just what I needed to know. Update: tried the test and the fan stopped. Also tried it at 2000 revs and it stopped.
I have fitted the new one and after coming home last Wednesday I tested the fan.whilst the car was hot. I could spin the fan it was totally free to rotate. I thought that it should be stiff so as to provide the full effect of the fan on cooling.

Incidentally, I lost over 6 litres of coolant each way on the trip total 64 miles. Is this fan defective or its that how it is supposed to work?

The fan doesn't do much work when on the motorways, so although this is an issue, I don't think it's the underlying one. Have you taken the radiator off and run a hose through it? You should get a good flow. Probably better to fill it from the bottom and see how much overflows. Short of knowing what the cooling efficiency of the TD5 radiator should be (which someone like neilly or sierrafery may know?) so you can measure inlet and outlet temperature to tell you if the radiator is working correctly.
 
It's completely irrelevant to check the fan stationary cos the silicone within it is subject of centrifugal force too as to act well, if you fitted a new one you should have done the same test with hot engine running and if it stops like the other it's DOA (if it's some cheap one not OE it can be)...though as long as you are loosing so much coolant concentrate on that in the first place cos at such leak the pressure in the system can't build to normal and all the cooling effect is mixed up
 
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