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Old 16th October 2013, 06:53   #11
lovema75
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The thermostat sits on the bottom of the V:


8 hours labour is over the top. Yes the air box has to come out - a 10 second job as it just pulls out of rubber mounts! Do not let the garage over state the job.


However the fact that the cooling fan worked "after it was fiddled with" does not sound good, it needs to work promptly and reliably. You have to understand how it works:

The fan runs with either 2 or 3 speeds. When engine temp rises low speed will cut in which is usually enough. However fan also runs on low speed when the aircon is switched on, so after some years, low speed will wear out and fail first. That's why we are suggesting checking if it runs when operating the aircon - if not then there is a problem which must be fixed.

If low speed has failed then the engine will get hotter and hotter, until eventually high speed emergency will cut in, however by then it is on the threshold of danger. This can lead to the coolant boiling and overflowing, even with the fan running. This is why a faulty fan could be the root of your problems, and why it must be checked.

Understand also that the temperature gauge is next to useless - it is designed to remain still between 75 and 112oC, so when it does finally rise it is often too late. It may as well be painted onto the dial.

Carry out the check indicated by Stocktake above, and post the result. The V6 cooling system works perfectly well if all the components are in good condition, so once the fault is found and repaired you will have no more issues. Blind guesswork however will lead to disaster!

Alternatively, if the cooling fan is working correctly following your tests, then follow the advice given already and check for coolant in the engine V, a sure sign the plastic thermostat housing has split and is leaking.

Last edited by lovema75; 16th October 2013 at 08:55..
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Old 16th October 2013, 09:53   #12
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Thank you so much for these guides! I will test the cooling fan when I get the car back..theyve had it for 22 hours..

Update!

Garage done a pressure test and it seemed to be leaking water from the cooling pipes. Apparently its corroded in. I think I need 2 of these? And also a silicon hose with bleed screw/valve.

I was told to find a kv6 metal cooling pipe if I could as John Grose may not be able to get the parts.

I was quoted 77 for cooling pipes and 41 for silicon and 80 for labour.

He doesnt think its the thermostat because theres heat in the car and its leaking water from the pressure test.

He said the pipes are like the letter L?

Could the pipes be the issue then?

Last edited by Dragrad; 14th November 2013 at 01:40.. Reason: consecutive posts - use the Edit ;-)
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Old 16th October 2013, 16:19   #13
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Leaking pipes certainly won't help, but a scattergun "replace em all" approach seems a little over the top.

However you are currently at the mercy of the garage. Dependent on the year of your car, the metal coolant pipes may be unavailable, however some owners have simply replaced them with new lengths of hose.
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Old 16th October 2013, 16:25   #14
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If pipes are leaking could it still be the thermostat

Cuz if the water is leaking, why would we say the thermo is caussing the overheat?

Or is it possible that with the thermostat going it could have damaged the cooling pipes?

Last edited by Dragrad; 16th October 2013 at 23:42.. Reason: consecutive posts
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Old 16th October 2013, 18:07   #15
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Old 16th October 2013, 18:13   #16
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If you are loosing coolant than that will almost certainly cause overheating. I had the same issue with the lower coolant pipes. In had to buy second hand ones. Be warned that there are two types of these pipes. I'll see if i can find a picture of mine.

Thee are the pipes on my car, there is another type that have fatter pipes.
Attached Images
File Type: jpg lower pipe.jpg (94.7 KB, 24 views)
File Type: jpg lower pipe1.jpg (68.4 KB, 23 views)
File Type: jpg lower pipe2.jpg (72.8 KB, 23 views)
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Last edited by Dragrad; 16th October 2013 at 23:45.. Reason: consecutive posts
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Old 16th October 2013, 19:40   #17
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Im just hoping that the thermostat is alright and its the pipes that i need. Do you know where I can get these from?

I need a silicon hose with bleed screw, and a kv6 metal cooling pipe.
Although is my engine even a k series? I thought k series was the older engine? :/
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Old 16th October 2013, 19:57   #18
lovema75
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The KV6 was derived originally from the K series, although they really have nothing in common.

Doing the thermostat is not a disaster, its even possible to replace it without removing the manifolds.

Here is the thermostat with 2 of its outlets showing...


But unless you have seen the offending pipes its going to be difficult to know exactly what is required.

I'.also unsure on the insistance on "silicone" pipe, there are no slicone pipes fitted to the engine.

Last edited by lovema75; 16th October 2013 at 20:05..
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Old 16th October 2013, 19:58   #19
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Quote:
Originally Posted by galaxyclass View Post
Thee are the pipes on my car, there is another type that have fatter pipes.
I believe this is the pipe I need cuz he said they are welded together and have 2 right angles on it. Where can I buy this and the silicone hose with bleed screw?

Quote:
Originally Posted by lovema75 View Post
The KV6 was derived originally from the K series, although they really have nothing in common.

Doing the thermostat is not a disaster, its even possible to replace it without removing the manifolds.

But if the pressure test has failed on a leak, this is most likely the issue right? But if so, why did the radiator cap overflow with hot coolant from pressure?

Last edited by Dragrad; 16th October 2013 at 23:44.. Reason: consecutive posts
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Old 16th October 2013, 20:27   #20
lovema75
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Quote:
Originally Posted by BrainKing View Post
But if the pressure test has failed on a leak, this is most likely the issue right? But if so, why did the radiator cap overflow with hot coolant from pressure?
Thats what you need to find out!

You or your garage will need to be really methodical about this rather than just throwing new parts at it. Find out whats gone wrong.
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