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Old 1st November 2019, 20:26   #51
SD1too
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The bottom hose (the one containing the bleed screw) should always feel hot. When it's cold, the thermostat hasn't opened. It sounds as if the K-Seal is interfering with the thermostat operation.

There's nothing for it but repeated flushes. MGJohn adds Holts Speedflush but drives with it still in the cooling system for a few miles before draining. He swears by this method.

Simon
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Old 1st November 2019, 20:38   #52
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Thanks simon but iv repeatedly flushed the system about 10 times before i put a new thermostat in then another 10 after i replaced it iv also used 3 bottles of speedflush
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Old 1st November 2019, 20:44   #53
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Do you think they could be an air bubble behind the thermostat which is being pushed around as sometimes the hose is cold and sometimes its hot
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Old 1st November 2019, 20:47   #54
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Yes and I sympathise deeply. However the fact remains that if the bottom hose is cold there is no circulation. Even though you've replaced the thermostat, if K-Seal remains in the system it will contaminate the new thermostat.

Other people have had exactly the same trouble as you are experiencing. A member called Trevor, who I don't think is an active member any more, did countless flushes on his engine in an attempt to rid it of the devil's potion.

This is why it is irresponsible to use or recommend this stuff. But the problem is that people are attracted to quick, easy and cheap "solutions". Unfortunately K-Seal is not a solution.

Regarding an air bubble, you can address that by draining the cooling system fully and refilling it following the MG Rover approved method.

Simon
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Old 1st November 2019, 20:54   #55
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I'll have to keep flushing the system then even though before i flushed it i thought i got rid of it all then as soon as i refilled bled and started it there was copper specs in the expansion tank again. There is 2 minor leaks from 2 hose clamps could they have anything to do with it. Id also remind that the temperature was remaining between 90-92 degrees whilst driving its only when i was in traffic the temperature gradually rose to 100 the fan kicked in and stayed at 100 it didn't rise and didn't fall until i started moving or revved the engine then it dropped back down.
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Old 1st November 2019, 21:34   #56
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Iíve given you my thoughts and experiences on a troublesome V6 and sadly donít entirely agree with Simonís all will be OK if you use the Rover method approach. That the method should work - certainly, but that it is 100% successful - no. Sometimes you just have to think outside the box and apply unconventional methods.

I experimented with several different approaches, including compressed air to pressurise the system and bleeding air from the bleed screw while the engine was running, which is how I removed the final pockets of air after several runs.

Your running temperature is a bit hot, but nothing scary, I hope you found and removed the broken bits from the old bleed screw, which as Colvert says was probably leaking air into the system. Perhaps itís time to relax a bit, keep monitoring the temp if using the car, until you get the new parts and can be sure the system is 100% sealed and then battle can commence renewed.

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Old 1st November 2019, 21:39   #57
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Yes not knocking anyone and i appreciate everyone's advice but i thought with a stuck thermostat in the closed position the engine would be overheating whilst im driving which it isn't doing im going to have a pressure test done on it then fix any leaks i find then flush the system again along with another bottle of speedflush

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Old 1st November 2019, 23:25   #58
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Quote:
Originally Posted by racing green rover View Post
There is 2 minor leaks from 2 hose clamps could they have anything to do with it.
That's the sort of thing that prevents the system pressurising properly. I've had similar on my SD1 when a defective brazed joint on the metal expansion tank caused problems. Why don't you fix the minor leaks from the clamps?
Quote:
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... when i was in traffic the temperature gradually rose to 100 the fan kicked in and stayed at 100 it didn't rise and didn't fall until i started moving or revved the engine then it dropped back down.
The temperature should fall as soon as the fan starts running. If you remain stationary it should reach 96 degrees in a minute or two. Yours doesn't because your cooling system isn't sealed (the two minor leaks) plus you have an ongoing K-Seal problem.

One important point about the MGR bleeding method is that the starting point is a fully drained system including the cylinder block plug. I wonder whether those people who distrust this method have done this. Somehow I doubt it.

Simon
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Old 2nd November 2019, 01:21   #59
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I think the leak is coming from the coolant rail where it joins the rubber hose rather than the clamp itself
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Old 2nd November 2019, 10:28   #60
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Earlier this week ...
Quote:
Originally Posted by racing green rover View Post
... so im getting a stainless steel coolant rail.
It will be interesting to see what happens when this is fitted.

Simon
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