What is an acceptable coolant temp for a Defender 300tdi?

[86mud]

Hi all

Since installing a VDO temp gauge in my 1998 300tdi Defender 130, late last year, I have been really watching the water temp fluctuate.

During the heat SE Qld had in January, my water temp was sitting at 100 Degrees on the highway on the flat and at any hill temp would climb to 103-105. Even got to 110 going up a step long hill (Landsborough to Maleny)

Around town it sits about 90 degrees

So this week I installed a new radiator (old was not leaking but was starting to break down and probably clogged), new viscous fan and a new air con thermo fan (fitted a larger 12" Davies Craig) and new coolant. Water pump, thermostat was replaced 12 months ago.

So went for a burn last night around the streets and still temps are sitting at about 90 degrees on flat at 60kms and climbed to 93 going up hill. I will go for a burn down the highway tonight to see what the temp does.

Is this normal for a 300 tdi? There is nothing in front of radiator apart from insect screen. My truck does weigh 2.8t empty and running 285/75 MTZ tyres

Thanks

[ROMAROVER]

Reports in disco 1 section also tell of little improvement so any other feedback would be appreciated, my disco runs around town high 80,s to low 90,s, slow long hills will go to low 100, but cools to normal when descending, LR gauge never moves. temp measured at rear cylinder head.

[uninformed]

One of the biggest issues, as being reported here quite a few times, is air flow. The engine bay of the LR are not good at flowing air I.e. it dams up inside and air struggles to pass through the radiator.

[DeanoH]

Isn't there someone on here that successfully put a vent in the LHS guard to improve engine bay air flow and temps ?

Also, it may be worth having your old radiator 'top' tank removed and decrease the bypass hole size to allow more coolant flow through the radiator.

Deano :)

[86mud]

I have a vent cut into the left hand guard. Might look at venting the bonnet on the sides somehow, or on top of the bonnet. Anyone done this?

I do have the spare wheel mount in the middle

Old radiator was cactus. So a new one was purchased. Alloy core.

Thanks

[rover-56]

I have a 300tdi Defender that has that rubber seal at the back of the bonnet missing. I noticed a lot of hot air exits there at the rear of the bonnet.
Might be useful to remove it if it is still fitted.

Not really sure why it has to be there? maybe keeps the hot air away from the fresh air vents?

Terry

[roobar_and_custard]

I have seen defenders with bonnet venting added (round holes) down the sides of the bonnet towards the rear (per attached).
I had a series rover which had louvre vents on the top of the bonnet.
No idea how well any of these work...

My 200Tdi "overheated" for a while, I recored the radiator to no real effect, but then changed the earthing strap on the engine - issue fixed!
Worth a try?

Also, the temps you state aren't really that hot. The engine should hold 90degrees(ish) depending on your thermostat, but when pushed hard temps into the 105degree range shouldn't be a problem, but probably an expert should jump in here.

[86mud]

I think I have vent envy! Just searched on Serge's LH guard side vent and my vent would be a quarter of the size!

So.....grinder time!

Will try this first

Thanks

[ajge]

Hi
My 96 130 new vdo gauge and sender, sits on 80 to 83 for general driving. Max I have seen is 93 on a 40 deg day up a long hill. These temps are confirmed with a sensor bolted to the thermostat housing.
I have removed the air-conditioner thing from in front of the radiator tho.
Regards
Andrew

[uninformed]

I think I have vent envy! Just searched on Serge's LH guard side vent and my vent would be a quarter of the size!

So.....grinder time!

Will try this first

Thanks

If I was doing it again, I would make the bottom go a bit lower. There is room and no reason not to.

Another member here did wool pile testing and the bonnet is pretty much no good for venting hot air out.

For air to move through the radiator, it must be able to enter and exit. A custom snorkle would also allow the right side intake (300 Tdi) to be used as a engine bay vent.

[tbdefender]

isn't temp related to thermostat rating??

What temp rating is your thermostat and when did u last change it?

[2stroke]

Used to have VDO electric water temp and oil pressure gauges on my 300 Tdi 130 and often got high temp readings as well as low oil pressure readings, particularly when the headlights were on. Tried heaps of things regarding earths etc, nothing changed. Ended up putting on VDO mechanical ones same time as I did the pyro and boost gauges. Mechanical seems much better, thermostat is 88 deg and you can see that the gauge is in agreement. Turns out she's running much cooler and with much better oil pressure than I thought.
I also did the vent on the LH guard and the mesh gets warm so it must be doing something. My feeling is that the best place for a vent is where it can eject hot air from the turbo.

[Dougal]

With a 15psi cap on the cooling system your water won't boil until 120C.

What is the concern with 93C?

[86mud]

I am running the mechanical/capillary VDO water temp gauge. And the radiator cap is new as well.

Thermostat is exactly 12 months old. and from memory is 88 Degrees.

IS there a cooler one available?

[vnx205]

I am running the mechanical/capillary VDO water temp gauge. And the radiator cap is new as well.

Thermostat is exactly 12 months old. and from memory is 88 Degrees.

IS there a cooler one available?

Why?

A cooler thermostat doesn't set the maximum temperature. It sets the minimum temperature.

Low Temp Thermostats: What’s the Advantage? | Tuner University (http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/)

[uninformed]

Why?

A cooler thermostat doesn't set the maximum temperature. It sets the minimum temperature.

Low Temp Thermostats: What’s the Advantage? | Tuner University (http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/)

yes, but they are not just open or shut, they are progressive. So a 82c cracking t/stat will flow more water at 88c as will the one that is just opening at 88c.

Dougal, I agree that cool temps may not be ideal. Not best for efficency or wear, but the LR cooling system is not a big enough heat sink to deal with load in summer. Load the truck/engine up in summer and the cooling system can not deal with it and starts pushing over 100c. Not ideal for road trips. Little spikes ok, but not sustained

My light 110 runs around at 82-88c in town and on normal HWY. But going up the Toowoomba range (empty, still light) can see the temp get to 100c.
And that not on a hot day, half way up the ambient temp is dropping noticably.

Towing my trailer out west (dead flat roads) I had to sit on 90-95km/h just to maintain 93c. If I sat on 100km/h it would go up to 100c. 800Km of 100c or more wasnt a good idea in my book.

Yes there is a Tridon 82c T/stat

[86mud]

I am yet to test on highway, so tonight I will be doing a 40km run up the highway to a friends house. I will report back with temp readings.

I thought there was only one thermostat available for the 300TDI - which is 88 degrees.

Thanks

[Dougal]

yes, but they are not just open or shut, they are progressive. So a 82c cracking t/stat will flow more water at 88c as will the one that is just opening at 88c.

Dougal, I agree that cool temps may not be ideal. Not best for efficency or wear, but the LR cooling system is not a big enough heat sink to deal with load in summer. Load the truck/engine up in summer and the cooling system can not deal with it and starts pushing over 100c. Not ideal for road trips. Little spikes ok, but not sustained

My light 110 runs around at 82-88c in town and on normal HWY. But going up the Toowoomba range (empty, still light) can see the temp get to 100c.
And that not on a hot day, half way up the ambient temp is dropping noticably.

Towing my trailer out west (dead flat roads) I had to sit on 90-95km/h just to maintain 93c. If I sat on 100km/h it would go up to 100c. 800Km of 100c or more wasnt a good idea in my book.

Yes there is a Tridon 82c T/stat

Is 100C a problem?

[tbdefender]

I am yet to test on highway, so tonight I will be doing a 40km run up the highway to a friends house. I will report back with temp readings.

I thought there was only one thermostat available for the 300TDI - which is 88 degrees.

Thanks

Pretty sure I'm running the tridon 82deg, reason being my 110 wasn't heating up fast enough and stay 'too cold' for my liking. Was the Thermo not completely shutting so new one in. Honestly, as much as i don't want to admit it, i think i got mine from super cheap auto.

[waltsd]

Is 100C a problem?

My disco 300tdi runs these temps. Up to about 106 on 40 plus days with air on and being pushed. Thought was normal?

Sent from my GT-S7500T using AULRO mobile app

[weeds]

I run a mechanical temp gauge.......new head and radiator 2 or so years ago

running to and from work at hiway speed is sits around 90 degrees.......

towing camper and pushing pretty hard on hills it gets up to 100 degrees than I back off a bit

have seen 105 degrees ish a couple of times

[uninformed]

Is 100C a problem?

It is when you are only just maintaining 100c by nursing it any push and it climbs further, and that on flat roads! A larger cooling system could still have the operating temp at 90c, but deal with load and ambient temp better.

Do you think a 2070kg truck should go over 100c maintaining the speed limit, what would I have reached if towing my trailer on a hot day up this range? And that is with no AC condesnsor in front, a lower cracking t/stat and a large vent cut in the left guard.

[Dougal]

It is when you are only just maintaining 100c by nursing it any push and it climbs further, and that on flat roads! A larger cooling system could still have the operating temp at 90c, but deal with load and ambient temp better.

Do you think a 2070kg truck should go over 100c maintaining the speed limit, what would I have reached if towing my trailer on a hot day up this range? And that is with no AC condesnsor in front, a lower cracking t/stat and a large vent cut in the left guard.

I see your problem now.

Have you got a flow/pump problem or problem with the flow bypassing the radiator?
I'd rig up a thermometer lead in the engine bay you can shift from place to place. Put it on each radiator tank in turn and see if you are getting that 100C water to the radiator and if the radiator is cooling it down enough on the way through.

[uninformed]

IMO it is a common problem that most dont know about as the stock gauge masks it. I still had this problem when I installed a brand new 2.8tgv with brand new t/stat and brand new radiator. (t/stat was changed for another to rull it out)

Maybe my 2 inch spring lift does not help? Maybe my low profile winch and winch bar does not help? But these are common items that should be able to be installed without pushing the limit to failure.

The LR Defenders need the A/C fan as the stock viscous and engine bay air flow will not push enough air through the radiator.

Installing the 82c t/stat made a small difference. Cutting the vent hole made a greater difference.

Remember the LR radiator is only 2/3 width of grill. I doubt many small trucks/4x4 have a radiator as small as LR.

[Dougal]

IMO it is a common problem that most dont know about as the stock gauge masks it. I still had this problem when I installed a brand new 2.8tgv with brand new t/stat and brand new radiator. (t/stat was changed for another to rull it out)

Maybe my 2 inch spring lift does not help? Maybe my low profile winch and winch bar does not help? But these are common items that should be able to be installed without pushing the limit to failure.

The LR Defenders need the A/C fan as the stock viscous and engine bay air flow will not push enough air through the radiator.

Installing the 82c t/stat made a small difference. Cutting the vent hole made a greater difference.

Remember the LR radiator is only 2/3 width of grill. I doubt many small trucks/4x4 have a radiator as small as LR.

This is a disco solution I found to the needle problem, but it might apply to yours too: Google Translate (http://translate.google.com/translate'sl=auto&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fwww.landroverclub.com.ar%2Fviewtopi c.php%3Ft%3D85)

I think some quality time with a thermometer you can read while driving will show the best areas to improve. It's very easy to spend time applying fixes which will help a little but not solve the actual problem.

The three big questions would be:
1. Coolant flow through the radiator.
2. Airflow through the radiator.
3. Fan.

I'd go for the radiator outlet tank tempearature first. If that's hot then the radiator isn't getting the heat out.
If it's cold, then you don't have enough water flow through.

[Jeff]

My Defender is getting older and towing on long trips the standard gauge gets up towards the red. I wonder if the radiator is getting old as most cars this age have probably had them replaced, so am contemplating an Allisport radiator for better cooling when towing.

On other threads some have modified the bleed hole in one of the tanks, not sure if this will help.

Jeff

:rocket:

[86mud]

Well folks I am happy to report that I just completed an 80km highway test in 30 degree heat. Coolant temp on the VDO gauge stayed at 90 degrees. Even when pushed to 110km/hr up a hill only rose to 91 or 92.

I am happy now...highway temps have dropped by nearly 10 degrees!!

Sorry about the picture quality...the whole multitasking thing is not one of my strong points :D

[uninformed]

Well folks I am happy to report that I just completed an 80km highway test in 30 degree heat. Coolant temp on the VDO gauge stayed at 90 degrees. Even when pushed to 110km/hr up a hill only rose to 91 or 92.

I am happy now...highway temps have dropped by nearly 10 degrees!!

Sorry about the picture quality...the whole multitasking thing is not one of my strong points :D

What did you change?

[86mud]

Well Wednesday I installed new radiator, new viscous fan, new larger air con fan and new coolant. I only got a chance to drive around the streets at 60kms/hour that night.

Out on the highway was where I was previously really worried about coolant temps around 100 degress, so today was the first time I had a chance to drive at 100km/hour since installing new radiator etc.


Difference is huge!

[uninformed]

Well Wednesday I installed new radiator, new viscous fan, new larger air con fan and new coolant. I only got a chance to drive around the streets at 60kms/hour that night.

Out on the highway was where I was previously really worried about coolant temps around 100 degress, so today was the first time I had a chance to drive at 100km/hour since installing new radiator etc.


Difference is huge!

What radiator did you go with?

[Sirocco]

I found it depends on ambient temps.

Since being in Aus (November) my cooling system wasn't great. When temps got upto 40-45c it struggled. Did a few things and it improved. Its now good and sits at 90 again with 95 when pushed hard and ambient is 35+

However, the truck is now empty and I use it to commute. So I dont know whats going to happen when its loaded again and towing the sankey! We will see.

UK built 90, not designed for Aus :( could do with some AC!

G

[PAT303]

I've never had cooling issue's with my Tdi until a few days ago,I run a Ford XE fan and the front seal let go and it spat all the fluid out so the fan just free wheeled.It's been doing alot of towing in high 40 degree heat as I've moved south of Perth and I've not had to nurse it at all until the viscous failed. Pat

[uninformed]

I've never had cooling issue's with my Tdi until a few days ago,I run a Ford XE fan and the front seal let go and it spat all the fluid out so the fan just free wheeled.It's been doing alot of towing in high 40 degree heat as I've moved south of Perth and I've not had to nurse it at all until the viscous failed. Pat

do you have any spring lift?

do you have any bullbar or accessories?

[PAT303]

Took all the crap off the front of both my defenders when I was living in the Pilbara and I'm very anal about correctly servicing the cooling system in my vehicles.I think the Ford fan helps the Tdi. Pat

[86mud]

Serge, I picked up an alloy core radiator through British off road. I did have the option to get a oem copper.core, but preferred aluminium.

I am just sitting at coolangatta airport waiting collect my boys. The run from Brisbane was very hot outside with 36 degrees ambient temps. Sat on 110km/ hour and coolant temp read 91-92 and did not fluctuate even up hills. Very happy!

[PAT303]

Serge,I thinking along the lines of Dougal and think your fan could be an issue.Have you gotten it up to temp and jammed a paint brush into it to see if it stops?.If you have to nurse it on the flat to stay under 100 somethings a miss. Pat

[redrovertdi]

Serge, I picked up an alloy core radiator through British off road. I did have the option to get a oem copper.core, but preferred aluminium.

I am just sitting at coolangatta airport waiting collect my boys. The run from Brisbane was very hot outside with 36 degrees ambient temps. Sat on 110km/ hour and coolant temp read 91-92 and did not fluctuate even up hills. Very happy!


Unscrew your capilliary temperature sender and put it in a pot of water and bring to the boil[portable gas stove], i did this with my vdo capilliary sender and in boiling water the gage only read 94, now removed and replaced with a auber instruments digital gage[tested against my flir thermal imaging camera to be accurate] that also controls my twin thermo fans[vt commodore] to cut in at 100 and cut out at 96

[uninformed]

Serge,I thinking along the lines of Dougal and think your fan could be an issue.Have you gotten it up to temp and jammed a paint brush into it to see if it stops?.If you have to nurse it on the flat to stay under 100 somethings a miss. Pat

That was towing 2 tonnes out west to Charlieville in peak summer (mid to high 30s)

Empty I can maintain 88c at 100km/h