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Engine temp guage

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Old 11-17-2013, 11:43 AM
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Default Engine temp guage

First off, I tried the search engine, and it was not working possibly due to me using a mobile app so I apologize in advance if there are threads already for this (I'm sure there are). I recently just had my radiator, water pump, thermostat and temp sensor replaced due to some overheating issues. My temperature gauge is currently not working, I had hoped it was due to a bad sensor which is why I replaced it. I have not really dug into things yet due to my schedule but any insight you vets could provide would be greatly appreciated. It was not working prior to the overheating either, I had gotten the read light indicator which lead me to the overheating issue. I just purchased the vehicle a couple weeks ago.
 
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Old 11-17-2013, 11:58 AM
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scan gauge, or ultra gauge, or aftermarket with sender
the factory gauge is a useless waste of space
 
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Old 11-17-2013, 12:11 PM
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A. Welcome

B. Since you say red light came on, we can assume that you have a Discovery 2. It helps to include that. The red light comes on at 284F, to warn you that engine damage has likely been done and prepare for overcharging at stealership. That is if system is working.

It may be your lucky day. If the engine coolant sensor is "open circuit" it can make the sensor read zero and the red light on to prompt you to service it. It is top center of engine between alternator and compressor. Be sure it is plugged in.

C. Normal temp would be in the 195-205 range, and electric fan (if not broken) will come on at 212F.

D. The RAVE is the factory shop manual and circuit manual and owner manual for your new toy. Free download below. The text that covers the gauge includes this on page 1494 of 1529:

The engine coolant temperature gauge is an analogue gauge with three sections: cold temperature; normal operating
temperature; high temperature. Under normal engine operating temperatures the engine coolant temperature gauge
will display in the centre of the gauge. When the engine is cold e.g. from first start-up, the coolant temperature gauge
will display in the cold band. When the engine is over heating the temperature gauge will display in the high
temperature band. If the engine coolant temperature gauge receives no input or the input is out of range the
temperature gauge will read cold and the high coolant temperature warning lamp will be illuminated.

The input signal is a PWM signal from the engine coolant temperature sensor via the ECM. The power input for the
high coolant temperature warning lamp is supplied by the instrument pack via fuse 27. The ECM controls the earth
path to illuminate the high coolant temperature warning lamp.

In other words, the gauge points at 50% from about 130-240F, so you really don't know when overheating begins..... until it is already Mongolian BBQ. Anything above 50% is too hot. Many owners use and OBDII connected scanner, like the $70 Ultra Gauge, to keep an eye on this. Note in pix that both gauges point to same spot, but temp is quite different.

Also, there is a different thermostat that should have been used, available mail order from places like Rovers North. Real Land Rover part, not the Motobad knock off. About $60. Runs truck at 180 ish instead of 199-210 ish.

How serious is this? Head gaskets frequently fail around 235 at extended running time. Enough overheat, and the cylinder liner will break loose and begin to "tick" as it travels. Rover engines hate over heat, but have gauge operation that "lulls" unsuspecting owners to ignore what becomes and engine killing problem in short order.
 
Attached Thumbnails Engine temp guage-bc8afb25-b563-4331-bdd7-c77d9c7f7685-8721-00000924dc11272f_zps3eba1104.jpg   Engine temp guage-pittsburgh-20120905-00034.jpg  

Last edited by Savannah Buzz; 11-17-2013 at 12:16 PM.
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  #4  
Old 11-19-2013, 05:45 PM
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Originally Posted by Savannah Buzz
A. Welcome

B. Since you say red light came on, we can assume that you have a Discovery 2. It helps to include that. The red light comes on at 284F, to warn you that engine damage has likely been done and prepare for overcharging at stealership. That is if system is working.

It may be your lucky day. If the engine coolant sensor is "open circuit" it can make the sensor read zero and the red light on to prompt you to service it. It is top center of engine between alternator and compressor. Be sure it is plugged in.

C. Normal temp would be in the 195-205 range, and electric fan (if not broken) will come on at 212F.

D. The RAVE is the factory shop manual and circuit manual and owner manual for your new toy. Free download below. The text that covers the gauge includes this on page 1494 of 1529:

The engine coolant temperature gauge is an analogue gauge with three sections: cold temperature; normal operating
temperature; high temperature. Under normal engine operating temperatures the engine coolant temperature gauge
will display in the centre of the gauge. When the engine is cold e.g. from first start-up, the coolant temperature gauge
will display in the cold band. When the engine is over heating the temperature gauge will display in the high
temperature band. If the engine coolant temperature gauge receives no input or the input is out of range the
temperature gauge will read cold and the high coolant temperature warning lamp will be illuminated.

The input signal is a PWM signal from the engine coolant temperature sensor via the ECM. The power input for the
high coolant temperature warning lamp is supplied by the instrument pack via fuse 27. The ECM controls the earth
path to illuminate the high coolant temperature warning lamp.

In other words, the gauge points at 50% from about 130-240F, so you really don't know when overheating begins..... until it is already Mongolian BBQ. Anything above 50% is too hot. Many owners use and OBDII connected scanner, like the $70 Ultra Gauge, to keep an eye on this. Note in pix that both gauges point to same spot, but temp is quite different.

Also, there is a different thermostat that should have been used, available mail order from places like Rovers North. Real Land Rover part, not the Motobad knock off. About $60. Runs truck at 180 ish instead of 199-210 ish.

How serious is this? Head gaskets frequently fail around 235 at extended running time. Enough overheat, and the cylinder liner will break loose and begin to "tick" as it travels. Rover engines hate over heat, but have gauge operation that "lulls" unsuspecting owners to ignore what becomes and engine killing problem in short order.
Excellent write up. I'm just about to fit an after market temperature and oil pressure gauge as the old truck is pushing on in years/miles and I don't trust the LR gauges anymore. The only use for the LR temperature gauge, is as Savannah Buzz says, knowing when your engine's overheated and 'lunched' but it can be used as a comparison double check against the after market gauge. I like the look of the Ultragauge I'll check out whether it's available in europe.
 
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Old 11-20-2013, 05:30 AM
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I just checked out the Ultra Gauge website and unfortunately the TD5 2.5L engine is not OBDII compliant and so the gauge is unlikely to work on mine.
 
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Old 11-20-2013, 07:47 AM
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i've been looking for something like this.

haven't found the right one yet.someone on this forum had a pic. of a nice looking one...forgot who
 

Last edited by dusty1; 11-20-2013 at 07:50 AM.
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Old 11-20-2013, 05:20 PM
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Originally Posted by dusty1
i've been looking for something like this.

haven't found the right one yet.someone on this forum had a pic. of a nice looking one...forgot who
You mean something like one of these Dusty Oil & Water Temp Gauges, Turbo Boost Gauges, Oil & Fuel Pressure Gauges | Smiths, Stack, VDO - Demon Tweeks

Look under 'display', 'dual analogue' there are a few shown.

I'll take a look around on this side of the pond for something at a reasonable cost as Demon Tweeks are way over priced.
 

Last edited by OffroadFrance; 11-20-2013 at 05:23 PM.
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Old 11-20-2013, 06:12 PM
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nice find. I like these. pricey though. this is exactly what I am looking for http://www.demon-tweeks.co.uk/motors...ure-dual-gauge thanks for link
 

Last edited by dusty1; 11-20-2013 at 06:22 PM.
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Old 11-20-2013, 09:15 PM
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I installed analog gauges on my instrument binnacle, but the ultragauge is nice since it also reads codes. With a TD5, gauges are your only option. I went with 1 1/2 inch autometer gauges. They aren't as easily read as the larger gauges but they are more than adequate for my needs: Installed New Gauges - Land Rover Forums : Land Rover and Range Rover Forum
 
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Old 11-21-2013, 05:22 AM
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I've used these gauges http://www.tomtop.com/car-accessories/other-for-cars , they work great and are also very cheap. Admittedly Smiths and Stack are good gauges (all probably made in China) but you pay top dollar for them. I have some of these gauges running in my Pajero and have checked and verified them and they are pretty accurate as good as any after market gauge. Check out the postage as I believe it's free worldwide. Admittedly, when auto road racing I used Stack displays ST8100 Dash Display but they had to be accurate with data logging abilities.

Another link which might be useful. http://www.banggood.com/buy/gauges/1...0-0_page1.html
 

Last edited by OffroadFrance; 11-21-2013 at 05:27 AM.


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