engine temp

[dee1]

I put an engine watchdog temp gauge in my Disco 1 300tdi during the week, and what a revelation that was. The factory temp gauge enters the normal zone at about 55 degrees and doesn't budge at least up to 98 degrees. So, begs the question, how hot is too hot for this engine? One of Melbournes stinking hot days recently, in traffic with air con on and 98 degrees was the hottest it got to before i got home. Now i'm concerned that the car is running far too hot. In the early hours of the morning it sits about 85 on the run to work.. Thoughts anyone?

[Judo]

Is the temp you're looking at coolant temp, or head temp?

Coolant temp can definitely get over 100 and my TDI always does if it's a hot day up a freeway hill. Mid 90's around town if it's hot and A/C on. I think anything upto 105 is probably OK, but past that I get very nervous! I'll let someone else comment exactly how hot is safe, but generally anything up to and around 100 is fine.

[dee1]

It's not coolant temp, the temp sensor is mounted under a bolt on the block. Would being bolted to the head give a more accurate reading?

[Judo]

I'm not sure it's more or less accurate - it's different.

TBH I'm not sure what head temp's are OK from a bolt on sensor. I don't have a head bolt sensor.

[SouthOz]

I have mine bolted to one of the bolts on the thermostat housing.

Dave

[Spel1]

It's not coolant temp, the temp sensor is mounted under a bolt on the block. Would being bolted to the head give a more accurate reading? Yes the stock gauge barely moves, and if it does its usually too late to make a difference. I attached mine to one of the thermostat housing bolts, closest to the original sender, and I think of any part in the engine the head would be the hottest, and would reflect the most and any immediate change. Overall all the metal in the engine would get to the same temperature eventually. Mine got to high 90s also last week in the Melbourne furnace with AC on. I have my watchdog warning set at 104 - I think somewhere on one of the posts they said that coolant cavitates at 115, so is set to warn me to back off or stop before getting to that.

[lane]

I spoke to my head mechanic, who I might add really knows his stuff and I can highly recommend, and he said that running any lower than mid 80's could harm the engine due to running too cool, somewhere between 85 and 95 is standard operating temps for those motors depending on humidity, outside temp, winds, and speed. He also said that damage to the alloy would start to occur at 120-125 depending on several factors such as if the motor had been overheated before etc. He wouldn't start to worry until he hit 105. Remember that whatever temp you start damage control the peak temp will be several degrees hotter. I have two electronic gauges fitted on my disco 300tdi auto here in Perth, (where we regularly see fairly hot days over summer and I live in the hills,) one TM2 fitted to the head on the spare threaded hole beneath No1 glow plug, (alloy conducts heat faster than steel) and a different branded one in my coolant at the thermostat. Both generally run at the same temp but the coolant is quicker to respond to changes i.e. it will rise and fall before the head temp. I see on an average trip through the suburbs around 86-89, pushing to 90-91 on hills. An extended run up Greenmount hill can see me hit 98 on a hot day with me thrashing the motor. I have a new rad, water pump, viscous coupling, thermostat, and Penrite coolant so is as close to new as I can get it! Don't worry if the temps fluctuate a lot as that is just the engine running as it should! I have my TM2 set to 97 but I am paranoid and cool it down long before that! The other gauge switches the aircon fans on at 89. So Dee1 your motor is running beautifully, just make sure you keep the servicing up to it and you (hopefully;)) will never have a problem! Hope this helps.

Lane

[omvanders]

I'm not sure it's more or less accurate - it's different.

TBH I'm not sure what head temp's are OK from a bolt on sensor. I don't have a head bolt sensor.

I've got the bolt-on version and my temps - and my thinking about those temps - are the same as Judos. The alarm is set at 106 degrees.

[James P B]

are we assaying that the vehicle gauge is not accurate? reason i ask is today my gauge hit the red out of the blue just after filling up driving along Gt North Hwy. Had to stop 4 times and could only travel a few lays before it would heat back up - coolant level was ok etc, then i opened the cap on the expansion tank a tad it burped a bit and then i drove the rest of the way of home without the gauge moving over half way which was another 25 minutes - go figure...

[lane]

are we assaying that the vehicle gauge is not accurate?Most definitely!:D They were built with a fifteen degree lag in the temp gauge so as not to frighten the posh drivers who were supposed to drive them! Add to that some Lucas electrics and age and you have a perfect time bomb!:wasntme: Mine has shown red hot when my other gauges were showing 82 and has been below normal running temp when the others showed 106! As well as it jumps a quarter whenever I switch my spotties on and another 1/4 when the aircon goes on! I don't even see it anymore when I scan my dash!:)

[dee1]

Thank you for all your helpful posts. Yesterday afternoon it peaked at 103. It was 40 degrees outside, sitting in traffic. It cools down reasonably quickly once it gets up a bit of speed. I notice the air con shuts off just over 100. I've only recently bought the car but the previous owner looked after it very well. 200k on the clock so I tend to think there is much life left in it. Meanwhile I might find a spot on the head to bolt the sensor and see if there is any difference.

[Spel1]

This thread got me thinking again of supplementary electric fans to help with high temps, or better utilising the two that are already there. FYI all my cooling parts are in new condition, rad, viscous fan, coolant, etc and all work fine in day to day conditions.

There are some situations where I drive at relatively slow speeds, up hills with load, trailers etc, so potentially not a lot of airflow and do push to 100º on rare occasions. In stock form, the AirCon fans cut in at 100º C, switches off at 94º C (according to all the books) to help cool things down without the AC running. So I figured I'd set up a manual control to switch them on earlier, but in looking into the circuitry (see attachment), the easiest thing to do was change the Thermo Fan Switch that is already there , to one that starts and stops at a lower temperature. The circuit is set up with a relay and everything. So, the replacement part I sourced from Tridon http://www.tridon.com.au/Products/Product.aspx?SG=8&S=35&G=483&P=2014 (after looking around for the specs, it has an M22 thread with 1.5mm pitch). One that switches on at 95º and off at 90º is part number TFS102. Its otherwise a direct replacement for the one that's there - X113 - see attached page from the Disco Electrical Troubleshooting Manual, bottom right photo. Ordered it from SCAuto for $35, no one I tried had one in stock. Repco price was $49 so shop around. I will post again if its all OK with a photo or two. Won't get the part till later in the week. Simon

[lane]

So I figured I'd set up a manual control to switch them on earlier, but in looking into the circuitry (see attachment), the easiest thing to do was change the Thermo Fan Switch that is already there

Mate the easiest thing to do, rather than spend $35-$50 bucks, is to negatively wire a $2.50 two way switch to the no.30 (if I remember correctly) terminal relay under the glovebox. Or if you don't smoke remove the ash tray and whack a spare landrover switch panel with switches (same as on the drivers side, they fit interchangeably) from a wrecker and it looks completely factory. Works great for me as my led underbody lights are wired from the left side so there was no fiddling with wires behind the stereo and aircon controls as that can be really hard and painful! (Think cut knuckles from all those nice sharp edges landrover left behind there!):)

Lane

[Gary S11]

How much are these after market " under bolt" type temp gauge? .

[lane]

How much are these after market " under bolt" type temp gauge? . Depends on what you get. A TM2 watchdog is about $150 or these Digital Temperature Controller Thermostat 12V 10A Switch 40„ƒ 120 (http://www.ebay.com.au/itm/Digital-Temperature-Controller-Thermostat-12V-10A-Switch-40-f-120-f-w-Sensor-/400610014265?pt=AU_B_I_Electrical_Test_Equipment&hash=item5d4637b439) are about $10.50 with a relay output. (To switch fans on and off when it rises or falls above a set temp)
I have both, TM2 I know I can rely on to be always accurate. I've had one of the other ones pack up but I have mates who have run them for years with no problems. To use the cheap ones under a bolt just flatten a piece of 1/2in copper tubing around it, with some solder or glue if you like, and drill a hole in it the size of your bolt. Works great. I glued mine in a threaded plug which I screwed in the top of the thermostat housing with some of the probe exposed to the water. Its a nice cheap option if you can't afford an exxy one and they are accurate until their not at which point its just goes haywire so you know not to trust it anymore and buy another one!

[Spel1]

Mate the easiest thing to do, rather than spend $35-$50 bucks, is to negatively wire a $2.50 two way switch to the no.30 (if I remember correctly) terminal relay under the glovebox. Or if you don't smoke remove the ash tray and whack a spare landrover switch panel with switches (same as on the drivers side, they fit interchangeably) from a wrecker and it looks completely factory. Works great for me as my led underbody lights are wired from the left side so there was no fiddling with wires behind the stereo and aircon controls as that can be really hard and painful! (Think cut knuckles from all those nice sharp edges landrover left behind there!):)

Lane

Mate, I'm happy to go with the $35 original position replacement switch - its not a lot of money for a useful control, and keep the ash tray for coins. I posted this information for those that are not into saving $32.50 as their main concern, but to help with keeping temperatures below 100º using as much original equipment as possible. No fiddling behind anything anywhere and nothing painful. This would be something that makes the electric fans that are there, work as they should in our hotter conditions here without manual control. Its not just about saving money, you have a Land Rover and generally you spend one way or the other - but I'd rather spend a little money on potentially functional stuff than underbody lights.

[lane]

No worries, you have a great idea there though. One that had never even crossed my mind!:) I don't know whether different years had different temp switches though as mine definitely doesn't come on at 100. But I'm with you on having the extra cooling capacity even though all components are in top condition. I'm currently researching engine oil coolers as, according to several diesel and truck mechanics I've spoken to, cooling the oil is just as important as cooling the water! As we all know oil holds more heat than water and is more reluctant to let it go. They all reckon the biggest mistake when fitting an aftermarket oil cooler is to keep the original rad cooler as it just adds more heat to the oil! And the oil, which stays hotter longer than the water because of it's position in the rad actually heats the water up! Especially offroad where airflow isn't great but engine temps can run high.


but I'd rather spend a little money on potentially functional stuff than underbody lights. What can I say! I'm in my twenties and they were $17 on ebay!:D Had to treat myself after the thousands I've spent on keeping her on the road!:mad:

[James P B]

Lane have you fitted a different engine oil cooler, i am planing to do the same and was wondering where u were thinking about fitting

[lane]

Not yet.:( Like I said still looking at options. There are two spots I would fit it, in the engine bay on the drivers side where the spare jack is on some models, which would keep it nice and clean but would need quite a powerful fan to keep the airflow through it. Or underneath somewhere on the drivers side, which has other pros and cons such as clogging the fins with mud, damage is more likely to occur from stray stones etc. but has more airflow. There are options such as fitting a stone guard without damaging cooling capacity as you need a fan on an underbody one anyway. However with the engine bay one I'm thinking of fitting a bonnet vent to increase airflow throughout the engine bay (think v8 cruiser size) which would help with the cooler but you have to be careful with that. There's a thread going atm about it. You can buy oil coolers with the piping from Veale auto parts for about $300 or SCA for about $125! And basically the same item quality wise though I think the cheaper one doesn't have a fan that comes with it in the box. The main thing is to bypass the rad cooler though.

[Discomark]

How much are these after market " under bolt" type temp gauge? .

I've got a couple of different types but these $20 ones work just as well as the $100+ ones in my opinion.
DC 12V Digital Temperature Controller Thermostat C | eBay (http://www.ebay.com.au/itm/DC-12V-Digital-Temperature-Controller-Thermostat-C-/290567953863?pt=AU_B_I_Electrical_Test_Equipment&hash=item43a7331dc7)

The only issue is they have a bullet type sensor so you need to make a holder to allow you to bolt it down to the head etc. A bit of copper formed around it has work well for me for the last 2 years.
They have a relay output so you can connect to a buzzer, light or fan controller relay.
Pics here http://www.aulro.com/afvb/discovery-1/174578-300tdi-operating-temperature.html
Cheers
Mark

[Dannyroger]

So what about 3.9 V8? Anybody know what temp range is normal for this? (or should this be a new thread?)

[lane]

So what about 3.9 V8?

Didn't know there were any left! I thought they all popped they're heads years ago!:wasntme:

Dunno what the the running temps should be but the peak temps mentioned earlier in the thread are the same for any alloy motor. Oh for the old iron series heads. Back in the sixties Len Beadell, the outback surveyor, once gouged a hole in the bottom of his Series II radiator with a sharp stump in the middle of the desert a thousand miles from nowhere. Of course there were no aftermarket temp gauges then so he didn't know he was overheating until all the water drained and the motor seized. After letting her cool down for some time he hammered a mulga root in the hole, filled her up with water, and turned the key. She fired first time. He then drove back to camp and, after fixing the hole properly, drove her back to Adelaide from the work site way out on the Gunbarrell hwy! You have to have some respect for any motor you can abuse like that!

[Gary S11]

I've got a couple of different types but these $20 ones work just as well as the $100+ ones in my opinion.
DC 12V Digital Temperature Controller Thermostat C | eBay (http://www.ebay.com.au/itm/DC-12V-Digital-Temperature-Controller-Thermostat-C-/290567953863?pt=AU_B_I_Electrical_Test_Equipment&hash=item43a7331dc7)

The only issue is they have a bullet type sensor so you need to make a holder to allow you to bolt it down to the head etc. A bit of copper formed around it has work well for me for the last 2 years.
They have a relay output so you can connect to a buzzer, light or fan controller relay.
Pics here http://www.aulro.com/afvb/discovery-1/174578-300tdi-operating-temperature.html
Cheers
Mark
Thanks, just purchased one on eBay....thanks

[lane]

I hope you didn't pay $20 bucks for a $10 item!;) They seem to be getting cheaper as two months ago the cheapest on ebay was $12.50!:D

[Gary S11]

I hope you didn't pay $20 bucks for a $10 item!;) They seem to be getting cheaper as two months ago the cheapest on ebay was $12.50!:D
NOW YOU TELL ME !
Oh well not to worry,. I didn't pay $20.00 ...I think it was $19.95

[lane]

NOW YOU TELL ME ! I did in an earlier post!;)


Oh well not to worry,. I didn't pay $20.00 ...I think it was $19.95 Ah, I don't feel so guilty now!:D

[Discomark]

I hope you didn't pay $20 bucks for a $10 item!;) They seem to be getting cheaper as two months ago the cheapest on ebay was $12.50!:D
That's cheap! I might pick up another one for the gearbox cooler.
I guess this is the one you referred to
http://www.ebay.com.au/itm/Digital-Temperature-Controller-Thermostat-12V-10A-40-f-120-Switch-f-Sensor-/190998540483?pt=AU_B_I_Electrical_Test_Equipment&hash=item2c786670c3
Cheers
Mark

[Discomark]

NOW YOU TELL ME !
Oh well not to worry,. I didn't pay $20.00 ...I think it was $19.95
Sorry Gary looks like they can be picked up even cheaper now. If it makes you feel any better I paid $25 for mine two years ago!

[lane]

I guess this is the one you referred to

No, the link I posted earlier in this thread!;)

[Ovadahill]

These are a little more expensive but I thought I would give it a go anyway when it turns up.

http://pages.ebay.com/link/?nav=item.view&id=231109165789

Sent from my GT-I9305 using AULRO mobile app

[Gary S11]

Finally got my temp gauge, slowboat from china. Started fitting it today. Took a ridicules amount of time to do such a small job.i ended up fitting it in place of the ash tray which I dont need. A big delay was finding a way through the fire wall on the left side of the engine bay.ended up going beside the rear washer pipe, had to extend the prob wire to reach, and then getting the thermostat bolt on the v8 was stupid . Picked up my power and earth from the LPG level indicator ..but very impressed with the unit. Took it for a run up our steepest climb, air temp 36 deg, with the air cond flat out ...it rose to 98 deg and then dropped as I went over the top, std gauge never shifted off 1/2 .....WHAT IS THE NORMAL OPPERATING RANGE FOR THE 3.9 does any one know ?
The pic shows the ambient air temp in my shed..not nice..thanks for all the help guys ..Gary

https://www.aulro.com/afvb/images/imported/2014/03/1193.jpg