2003 S Type 2.5 petrol - Occasional water loss

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Wed 6 Mar 2013 06:47
2003 S Type 2.5 petrol - Occasional water loss - Touchy
Hi. My car is occasionally loosing water and the low coolant level warning light comes on. I have fitted a new header tank and thermostat pipe network, there are no signs of leaks, indeed the header tank retains pressure for several hours after the engine has been turned off. I have had it pressure tested and there are no issues there. I am now thinking that the water pump may be worn and require replacement. The car has covered 100,000 miles .
I can drive 100 miles in one hit without issue then the light may come on as I get into urban areas.
The car is fine for quite a while then the low coolant light comes on, stop the car for a while, maybe 10 minutes or even half an hour and the water level has returned to normal and the light has gone out.
How long should the water pump last?
Can they suffer for cavitation and can this cause the problem?
Is it possible for the hoses to collapse and restrict flow and therefore cause excess pressure and displace the water?

Any ideas or experience of this as it is doing my head in!
Tuchy
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Wed 6 Mar 2013 08:16
2003 S Type 2.5 petrol - Occasional water loss - Armitage Shanks {p}

Comment rather than answers I am afraid! What does the temperature gauge do while all this going on?

You say - "The car is fine for quite a while then the low coolant light comes on, stop the car for a while, maybe 10 minutes or even half an hour and the water level has returned to normal and the light has gone out."

On that basis you are not losing water

Have you looked on the net for a Jaguar owners forum? There must be one and I think you might find good info there - good luck and don't cook the engine!


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Fri 8 Mar 2013 07:46
2003 S Type 2.5 petrol - Occasional water loss - Touchy
Hi. Temp gauge normal as it has been for re last three years. I think there is air trapped in the system but no amount of effort to bleed the system seems to
clear it. I can set off water level in header tank at correct level, sometimes 5 sometimes 100 miles then the low coolant level light comes on. Stop the car and return 30 minutes or even overnight and no light! Water level ok! The new header tank fitted last year has a 140kpa pressure whilst the original one was a 120 kpa cap. Even swapped these around but it appears to make no difference.
This is so frustrating, but I will not be beaten!
Touchy
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Wed 6 Mar 2013 08:43
2003 S Type 2.5 petrol - Occasional water loss - TeeCee

Both a water pump problem and a collapsing hose would cause obvious overheating well before the coolant level warning came on.

That sounds more like something blowing into the system and displacing coolant into the expansion tank. Head gasket on the way out?

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Wed 6 Mar 2013 09:10
2003 S Type 2.5 petrol - Occasional water loss - Collos25

I agree,and the only proper way to check a head gasket is to remove the head.

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Wed 6 Mar 2013 10:22
2003 S Type 2.5 petrol - Occasional water loss - SlidingPillar

There is a chemical test for head gasket leaks applied to the coolant. No idea how reliable it is, but when shown to me in the early 80's by a garage proprietor it was a cheap test to do.

Idea basically was to avoid doing unneeded and expensive head jobs.

I had a car that always gave signs of leaks when you filled to the cold level - but if you let it drop, it got to the same amount below the level, and dropped no more. In other words, it was blowing the coolant out when it pressurised, but didn't actaully have a leak. Once I wised up to this, I never topped it up again in 50 000 miles

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Wed 6 Mar 2013 13:42
2003 S Type 2.5 petrol - Occasional water loss - Collos25

It could quite well be a faulty water pump or even air in the system but unless the fault is found and cured ASAP then I see the HG or even the head itself being ruined.

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Sat 9 Mar 2013 12:29
2003 S Type 2.5 petrol - Occasional water loss - Touchy
Hi guys. Thanks for the input it is greatly appreciated. I was thinking possible head gasket. Tried again yesterday evening to see if I could remove any air from the system by opening the bleed screw and running the engine to push the air out, if there is any. If no then ........££££ I hope not!
I will update as,when,if I ever get to the bottom of the problem.

Have a great weekend
Touchy
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Sat 30 Aug 2014 18:46
2003 S Type 2.5 petrol - Occasional water loss - mickanic
Hi guys. Thanks for the input it is greatly appreciated. I was thinking possible head gasket. Tried again yesterday evening to see if I could remove any air from the system by opening the bleed screw and running the engine to push the air out, if there is any. If no then ........££££ I hope not! I will update as,when,if I ever get to the bottom of the problem. Have a great weekend Touchy

Hi, Did you get to the bottom of this problem, as my friend has the same problem with his 2004 2.5 v6 be great to know how you got on !!

Thanks inadvance Mick

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Thu 7 Mar 2013 23:08
2003 S Type 2.5 petrol - Occasional water loss - Avant

Moved to Technical.

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Tue 2 Sep 2014 07:48
2003 S Type 2.5 petrol - Occasional water loss - mickanic
Hi guys. Thanks for the input it is greatly appreciated. I was thinking possible head gasket. Tried again yesterday evening to see if I could remove any air from the system by opening the bleed screw and running the engine to push the air out, if there is any. If no then ........££££ I hope not! I will update as,when,if I ever get to the bottom of the problem. Have a great weekend Touchy

Hi, Did you get to the bottom of this problem, as my friend has the same problem with his 2004 2.5 v6 be great to know how you got on !!

Thanks inadvance Mick

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Mon 13 Apr 2015 22:27
2003 S Type 2.5 petrol - Occasional water loss - terry k
Any updates my 52 plate is doing exactly the same ....
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