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Old 21st February 2018, 16:13   #11
kaiser
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thanks genpk. I guess it takes a couple of guys from the warm countries to tell the pommies what is going on with their cooling systems!!

But the good news is, that he V6 is not prone to HGF, so most likely your engine is till OK So cross fingers!
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Old 22nd February 2018, 03:14   #12
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I got myself a new cap (for $70, yikes) and the car ran for 40 minutes until it slowly got too hot.
I have now bled the system and will test again after I get back here in a couple of days.

I can't believe that that's all there is to it, but sometimes you can be really lucky
I wish I could test it properly now but I have to leave for a few days.

I was expecting to replace the thermostat so I figured why not get a few things done at the same time.
The front bumper is off so that I can fix that annoying panel gap most cars seem to have and I replaced the shannon tube whist at it and was able to clean everything under the engine to check for leaks. No leaks anywhere. Odd really but rather nice to know.

As it stands I am pretty sure it just needs the air removed and all will be well.

I have been up at nights quietly freaking out about head gaskets etc. Now I think I can sleep again.

Thank you all so much for the ideas. This people on this forum are the only reason I have stuck with this wonderful car. Without people like you I would have moved it on a few years ago out of fear of screwing things up.
You have all made me feel that if I have a go I can rely on considered responses and help when I need it.
Thank you very much.
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Old 22nd February 2018, 03:18   #13
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Quote:
Originally Posted by T-Cut View Post
What tests did you do?

TC
I did real time tests...

Fan kicks in at 100
Fan speeds up at 106
Another speed hike at 110
This kept it cool for a considerable time until it slowly rose to 115 at which point I shut it down.
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Old 22nd February 2018, 04:51   #14
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Quote:
Originally Posted by BaroqueMoon View Post
...

I have been up at nights quietly freaking out about head gaskets etc. Now I think I can sleep again.

Thank you all so much for the ideas. This people on this forum are the only reason I have stuck with this wonderful car. Without people like you I would have moved it on a few years ago out of fear of screwing things up.
You have all made me feel that if I have a go I can rely on considered responses and help when I need it.
Thank you very much.
Hello Matthew!
The same story with me.
Keep us in touch - it would be very interesting what exactly caused the hot problem.
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Old 22nd February 2018, 05:12   #15
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The engine should never get that hot with the fans working.
Your stat must be stuck, if you had a full system during test.
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Old 22nd February 2018, 05:17   #16
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Quote:
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The engine should never get that hot with the fans working.
Your stat must be stuck, if you had a full system during test.
If the coolant doesn`t move?
Imagine that the impeller of the water pump is worn out or there is an air pocket somewhere in the system.
Or clogging?
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Old 22nd February 2018, 06:04   #17
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An impeller that has come off the shaft or is corroded/worn away, could cause what is seen, but this is unlikely and very rare.
If there is an air pocket, then the water must have gone somewhere, and the system then has a leak!
That can be ascertained by checking the level once the car is cold. Press the top hose repeatedly and watch the level in the expansion box. If it sinks as you press, you are expelling air.
A total blockage of the system is also possible, but also rare. Maybe a problem with a hose de-laminating?

Of all the above, if circumstances are indeed as described, blocked passage caused by stuck thermostat is the most likely cause.
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Old 22nd February 2018, 06:08   #18
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Quote:
Originally Posted by kaiser View Post
An impeller that has come off the shaft or is corroded/worn away, could cause what is seen, but this is unlikely and very rare.
If there is an air pocket, then the water must have gone somewhere, and the system then has a leak!
That can be ascertained by checking the level once the car is cold. Press the top hose repeatedly and watch the level in the expansion box. If it sinks as you press, you are expelling air.
A total blockage of the system is also possible, but also rare. Maybe a problem with a hose de-laminating?

Of all the above, if circumstances are indeed as described, blocked passage caused by stuck thermostat is the most likely cause.
Ok. Looks like it's a fine time to replace the thermostat then.
Didn't think it could be as simple as replacing the cap.

Thanks Kaiser

Edit: Pressing the top hose moves a little water but the level is constant.
Running tests again right now...will report back in about 10 minutes.
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Last edited by BaroqueMoon; 22nd February 2018 at 06:28..
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Old 22nd February 2018, 06:55   #19
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Ambient Temp 22 in the garage. Nice day.

Testing at idle with a/c off.

After 6 minutes
Dash board Temp gauge at 9 o'clock
IPK reports 75 degrees

At 14 minutes
Temp hits 100
Fan starts

At 17 minutes
Temp hits 106
Fan increases speed

At 22 minute mark
Temp at 112
Fan increases speed

At 28 minutes
Temp 116
Dash gauge starts to move above 9 o'clock

Shutdown.

I have the front bumper off and the air box removed (I was getting ready to do the keyhole method of stat change) and with such good access I can see no leaks.

At least the thing isn't spraying water from around the cap. So that's a positive

The thermostat housing isn't leaking but it sure seems like a stuck thermostat.

Ah well...I was halfway done toward replacing it anyway.
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Membership Number 1703

This vehicle was the 82,624th 75 to run off the production line, out of 112,381
This vehicle was the 6,161st 75 2.5 V6 Contemporary to be made out of 8,214
This vehicle was the 9,755th 75 in White Gold Metallic (code: GMN) to be made out of 12,251 White Gold Metallic 75s
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Old 22nd February 2018, 08:57   #20
kaiser
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Yes there is a serious problem. A blocked stat fits the bill. Interesting to see what you end up with.
Cook the thermostat when you get it out, that should show you.
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