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Old 11th December 2020, 16:05   #51
macafee2
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Originally Posted by T-Cut View Post
The coolant temperature is displayed as whole numbers only, whereas the ambient is calibrated in 0.5 degree jumps. So, if the coolant was actually at 7.5C, then the coolant display would show 007. Did you see 075 for ambient under Section 7.1 or did you read that from the standard dash screen?

If you had successfully logged into Section 7.0, I'd expect to see maybe 008 or 010 following an overnight stand after driving. This would be due to the high thermal capacity of the engine. If it had all cooled down to ambient over several days, yet it read 000 then it suggests it's at zero Centigrade. Maybe it was still cold from an overnight standng in freezing weather? Once down to say 0C, warming up to the daytime ambient at this time of year is unlikely to happen. There's not enough time before it's night and freezing again. It's far more informative to watch the temperaturte rise with the engine running so you can access how well the thermostat is performing.

TC
From a previous post it looks as if I did it wrong, hence I got 000.
I will try again and hopefully do it right.
It will be an eye opener if at 9 o'clock it is still "cold" as I do get warm air.
I will have to visit this thread after testing again and seeing what the diagnostics display tells me.
I do not want to fit a digital display and I do not want to run in diagnostics mode, I would like the original gauge to be accurate.

If I fit the other inline stat that is recommended in this thread and that opens when the water is hotter, what can I expect to see when it comes to the needle? Will it sit between 9 and 10 0'clock or will it rise to between 9 and 10 and then the stat opens and the needle drops to 9?

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Old 11th December 2020, 18:52   #52
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Quote:
Originally Posted by macafee2 View Post
From a previous post it looks as if I did it wrong, hence I got 000.
I will try again and hopefully do it right.
It will be an eye opener if at 9 o'clock it is still "cold" as I do get warm air.
I will have to visit this thread after testing again and seeing what the diagnostics display tells me.
I do not want to fit a digital display and I do not want to run in diagnostics mode, I would like the original gauge to be accurate.

If I fit the other inline stat that is recommended in this thread and that opens when the water is hotter, what can I expect to see when it comes to the needle? Will it sit between 9 and 10 0'clock or will it rise to between 9 and 10 and then the stat opens and the needle drops to 9?

macafee2
It will sit at 9 o'clock.

It's worthwhile running the diagnostic mode for a few trips after you've replaced your stat.

You can then see the needle sits at 9 at 75c and stays there until you hit you target temp, and then it still stays there as the water circulates, cools and then gets hotter again.

Unless it goes over 105(?) It won't go above 9 o'clock.
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Old 11th December 2020, 20:11   #53
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... I would like the original gauge to be accurate.
It is accurate Ian, but it was designed to indicate "normal" (the nine o'clock position) for any temperature between 75 and 115 degrees. So the gauge is operating within its specification but that doesn't give the driver the information he/she needs.
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Originally Posted by Daveluck View Post
Unless it goes over 105(?) It won't go above 9 o'clock.
115 degrees Dave.

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Old 11th December 2020, 20:34   #54
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Quote:
Originally Posted by macafee2 View Post
From a previous post it looks as if I did it wrong, hence I got 000.
I will try again and hopefully do it right.
It will be an eye opener if at 9 o'clock it is still "cold" as I do get warm air.
I will have to visit this thread after testing again and seeing what the diagnostics display tells me.
I do not want to fit a digital display and I do not want to run in diagnostics mode, I would like the original gauge to be accurate.

If I fit the other inline stat that is recommended in this thread and that opens when the water is hotter, what can I expect to see when it comes to the needle? Will it sit between 9 and 10 0'clock or will it rise to between 9 and 10 and then the stat opens and the needle drops to 9?

macafee2
You do not and will not need to fit an additional gauge, I simply wanted to. I would actually be confident enough to not even have a working gauge with the diesel. All reports seem to suggest that over heating is extremely rare, and even if it did, it would be take it in its stride until you got stopped - the warning light would come on to warm you.

If you find that your thermostat is not allowing it to heat up to the magic 88 degrees (the tell tale is 82 and below), you will still get warm air, the problem is, as you use the warm air, the engine will cool yet more, but you will still receive warm air. The engine will still run fine, albeit a little less economically. Theoretically it will experience more wear, but in real world, I bet the rest of the car will expire first!

If you decide (or you 'need') to fit an inline thermostat, the chances are you will notice little difference, except if you turn the temp up to max. on the ATC, I found it noticeably warmer. With the ATC set to 22-24, there was no change. You may get a couple more mpg, but again, in real world situations, you may not even notice lol.

It doesnt have to be a Wahler stat. I have tried various brands, and all were not as good as the wahler. They are twice the price (£15 compared with £7.50) but they are also twice the quality. As long as the stat holds water in its bowl whilst it is cold, it should be fine, and you dont damage/distort it whilst fitting.

Incidentally, if you watch it at 74 degrees, you will see the gauge at around the 8 o'clcok position, as it turns 75, you will see the needle rise to 9 o'clock. I have only ever seen it rise above the 9 position, and at idle that was some wait! At that point the fan came on, (which was 105, it actually rose to 106 before it fell) and it rapidly fell back to 9 position, which was when I was fed up and embarrassed (it took about an hour, and I am sure my neighbours were wondering what i was up to!).
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Old 11th December 2020, 23:14   #55
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Default Engine Temp Run Out OBD Inline Stat.

As i started to read this thread early this morning, i decided that i would give the tourer a run out later today and take a few photo before, during and after i got back.

So to start with ignition to I

Press trip switch go to 19.
1

Then press when on the off sign go to 7.
2

It will read ---000

Turn ignition off then back on again ignition II without starting the car.

Press trip switch to 19.
3

Press when on off sign, go to 7.
4

It should give a reading mine was ---009

Next i took photo of time before starting the car for the tested journey.
5

Car started press trip switch to 19.
6

Then on off to 7. reading now is ---016
7

Set trip distance to 0.0 miles before setting out on the journey.
8

Even in that amount of time 3 minutes the reading temp as changed while on tick over, please take note of the time through out this thread on the camera & clock. ---044
8

Pulling off at 4mph reading is ---56
9

After 1.7 miles reading is ---063
10

3.5 miles reading ---081
11

4.3 miles reading is ---084
12

5.9 miles reading is now ---085
13

I am 18 minutes into the journey.
14

9.4 miles reading is ---084
15

I pull over in layby to take photo of the time, on the clock 15.10pm
16

Arrive back home clock reads 15.20pm
17

15.0 miles the journey finished back home reading is ---086
18

Fuel reading 37.6mpg driving roughly 35mph to 40mph reading as now reached ---087
19

Average mph 29.3 reading is still ---087 while ticking over.
19

Back to 0mph ticking over reading is ---084
20

So a 15 mile round trip in differing traffic thermostat fitted is a Gates which i prefer nice tight fit no bypass and doe's not need a second jubilee clip to keep it in hose correctly.
21


22

23

24

25

26

make sure there are no leaks after fitting.
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Last edited by Arctic; 11th December 2020 at 23:58..
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Old 12th December 2020, 10:59   #56
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Originally Posted by macafee2 View Post
I do not want to fit a digital display and I do not want to run in diagnostics mode, I would like the original gauge to be accurate.
That's not possible I'm afraid. The only way to get an 'accurate' reading is via the K-bus/diagnostic system. There'd be no need to fit aftermarket gauges if the one in the car operated sensiby. Unfortunately, MGR's styling gurus assumed 75/ZT owners wouldn't want to know such things.

EDIT: Altering the way the gauge responds to the sensor signal has been discussed umpteen times in the past and the conclusion thus far is it can't be done.


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Old 12th December 2020, 15:42   #57
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I do not want to fit a digital display and I do not want to run in diagnostics mode, I would like the original gauge to be accurate.

macafee2
Just putting it up to show you where I put mine. I did have to dim the brightness (by using a product called dimms- basically smoked clear vinyl sticker). But I think it works quite well. I would have preferred to be able to have it selectively displayed on the large ipk screen, as the speed can be, but hey ho.





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Old 12th December 2020, 18:50   #58
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Unfortunately, MGR's styling gurus assumed 75/ZT owners wouldn't want to know such things.
To be fair to MG Rover, I doubt that it was their initiative. I briefly owned a BMW 330i of the same era as the 75/ZT and its temperature gauge was exactly the same. I wouldn't be surprised if all the major manufacturers have followed suit. After all, it's a great marketing ploy that BMW and MG Rover engines are so technically advanced that they maintain a rock solid temperature in all conditions.

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Old 13th December 2020, 11:26   #59
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Am I running cold? Started the car and went for a drive and this time with ignition key at position 2, I got the temperature reading.

Having done about 12 miles mainly at 30, 40 and 50 the best I got was 81.
I think it made 83 on the way home. There was no load so to speak as it was just the wife and I on the way and return a load of empty boxes as well.
Am I running cold or cool? The dial was at the 9 o'clock.

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Old 13th December 2020, 14:36   #60
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Originally Posted by macafee2 View Post
Am I running cold? Started the car and went for a drive and this time with ignition key at position 2, I got the temperature reading.

Having done about 12 miles mainly at 30, 40 and 50 the best I got was 81.
I think it made 83 on the way home. There was no load so to speak as it was just the wife and I on the way and return a load of empty boxes as well.
Am I running cold or cool? The dial was at the 9 o'clock.

macafee2
How long did it take to reach 75?

At this time of year, and in these ambient temperatures, mine reaches 75 in about 3 miles. This is roughly 1 mile each of 30, 40, then 50 mph, and what I would describe as firm acceleration.

Following this, another 2 miles at varying 40-50 mph (and maybe a traffic light or two) it reaches 84-86 degrees.

After those 5 miles I reach the motorway and within a mile of accelerating to to 70/80 and cruising the inline stat has opened at 88/89 degrees. It maintains 84-86 until I park at my work, which is literally at the end of a slip road off the motorway.

So that is 6 miles variable speeds of 30-40-50-70 mph, it reaches temp. In the summer, it opens earlier at 5 miles and before I reach the motorway.

As well as this, I do not have the heater on. If you have the heater on after perhaps 3 miles I would suggest that it will not reach 86/88 by the 12th mile without much acceleration (ie no engine load), if you didnt exceed 50mph.

There are so many variables, it is difficult to measure. I am happy that it reaches the temperature, and it has a consistent pattern. But your description is similar to how mine would react if the heater was on early in the run.

If the heater was not used, I would suggest that whilst it seems like the stat is opening early (it does NOT have an inline if I recall) it is not bad, but would still benefit slightly to a decent inline stat fitted.

----------------------------------------------------------------------

Another test, if you can cruise, with no acceleration, along a motorway for 5 miles, after the temp has reached its max temp. The temp displayed should remain relatively constant, and that will give you an idea if the stat is opening early. The last time I did this, with a faulty stat, it maintained roughly 76 degrees - if the stat had been operating correctly, the temp would have continued to rise.
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