How hot is too hot?

[philandmickey]

Hi all

Had our first longish run in our 1996 130 with 196,000 km's.

I am preparing it as a long distance tourer so it is quite heavy probably just over 3 tonnes.

One of the mods I have fitted is an engine watch dog.

While driving up a long hill the temperature slowly rose to 97 at the top of the hill, it was a long steep hill (Wilunga hill for any SA people).

Not sure if this is too high and not sure how hot it would have got if the hill had been longer or the day hotter?

I have receipts for the radiator being cleaned out (Says was 30% blocked) 6000 km's ago from previous owner.

Apart from the hill the temperature sits at around 82.

So any advice anyone can offer would be greatly appreciated.

Phil

[Snail Bait]

Check your viscous fan clutch, my 95' 110 would get hot when towing or on the beach installed a new fan clutch no problem now.


Sent from my iPhone using AULRO mobile app

[Marty110]

Hi, I reckon that 97 is OK for a 300Tdi up Willunga Hill given your 3 ton estimate of weight. 82 is very good for normal running. What was the ambient on the day? How hard were you pushing the car?

[steveG]

I wouldn't be too concerned about 97deg. Where abouts is the sensor connected?
A few years back when I had my D1 I started off with the sensor on the LH side of the head near the thermostat housing but suspected that it was being influenced by the exhaust manifold when under high loads as it would climb higher and more quickly than I felt was real
Moved it to the RH side under a small bracket below the #1 injector and found it was much less reactive to high loads.

Check your viscous fan as snailbait suggested anyway.

Did you have aircon on? If you do, then turn it off if you're concerned about engine temp.
You can also use the heater as an extra radiator for additional cooling if you need to.
I've got an engine watchdog in my '98 Falcon (as well as my County), and if the head temperature starts to get up around the 97 deg mark (usually when stuck in peak hour traffic on hot days) I turn the heater and fan on full and its enough to hold that temperature or start to drop it. I'd rather sweat it out on a 40deg day with the heater on than replace another head :)

Steve

[philandmickey]

Hi
Thanks for replies

The temp for the day was 25ish.

AC not on.

Foot hard to floor with speed at 60 in 3rd by top of hill.

The watch dog is connected to a thermostat bolt, the temp gauge went up to just over 3/4 as well so I think it is reading reasonably correct.

Is there any way of testing the viscous coupling or is it a replace and see?

Phil

[Snail Bait]

My fan clutch was never engaging, with the new clutch you should be able to hear the fan working when first start up (cold) and after a long uphill.

[philandmickey]

Another thought I had was, would it help to put a switch on the thermo fan in front of the radiator, that currently comes on with the AC, so that I can have it on when needed?

Phil

[steveG]

A/C Thermo fan is only small and not ducted.
I doubt it would have much effect.
Think you can test viscous fan coupling using a paint brush or similar. Have a search here as I can't recall the details.

Steve

[roverrescue]

the temp gauge went up to just over 3/4 as

As mentioned previously across the forums. The OEM water temp gauge is normalised between about 80 and 110 degrees. The very moment it starts moving your water temp is over 110 degrees celsius.

Obviously if the external temp only got to 97 and didnt climb further you likely dont have issues such as head gasket but more likely radiator/viscous fan/ water pump.

I wouldnt lose too much sleep running up to 110 water temp on a long hill with a full load as l.ong as it comes back down afterwards but really it shouldnt get that hot.

S

[Bush65]

IMHO 97* is ok for a diesel, but the concern is what would it get to when the ambient temp is higher, the load higher .....

I don't know about the 300Tdi installation in a Defender, but in a disco, IIRC, there are 2 temperature switches (different colour for different set temperatures) in the thermostat housing, one disengages the clutch for the air con compressor and the other switches on the air con condenser fans (if not already on).

[86mud]

I recently installed a VDO water temp gauge and capillary sender in my 1998 300TDI.

It is interesting to watch the temp rise and fall when travelling up and down hills. Yesterday was about 33 degrees ambient temp and at 110kms/hr on the highway, my water temp gauge was sitting between 95 and 105 degrees depending on terrain.

My 130 sits at about 3 tons as well.

Cheers

[nedflanders]

What I've found with the TD5 is on a normal day (25deg ish) it will sit between 80-83 depending on traffic, throw in a decent hill and it's upto 87-89ish. I can hear the fan cut in at that temp and the engine temp drops rapidly back to 83. The thermostat is set for 83 as well I think and again I can usually tell that's kicked in.
When the ambient temp is hitting high 30's it only raises the normal operating temp by a couple of degrees.
I can also bring the temp down by slowing down and using a lower gear on the hills when towing, 5th gear at 80kph will get the temp close to the 90's no problem, drop it to 4th and it can drop temp by a good 5degs, guess more throttle equals more fuel equals running rich equals higher burn temp equals higher engine temp but I could be wrong.
My only concern with temp is gearbox, those suckers get ridiculously hot, already fitted extended t-box sump and fitting a better gearbox cooler soon.

[roverrescue]

John,
'Fenders dont run the A/C thermostats on the elbow such as discos.
Also really Phil is not running his diesel at 97 he is running the outside surface of the alloy head at 97... as mentioned if the OEM gauge is at 3/4 the actual coolant water temp is more like 110 maybe more.

Cooling system needs some loving IME

S

[nedflanders]

John,
'Fenders dont run the A/C thermostats on the elbow such as discos.
Also really Phil is not running his diesel at 97 he is running the outside surface of the alloy head at 97... as mentioned if the OEM gauge is at 3/4 the actual coolant water temp is more like 110 maybe more.

Cooling system needs some loving IME

S

On my TD5 when the engine Guardian reads 83deg (fitted on the coolant pipe entering the head) the Nanocom is reading 87deg at the coolant sensor.
Also my gauge reads in the normal position (just under half) when its anywhere from 60degs to 90degs, I suppose this is to stop drivers being paranoid with the gauge going up and down al the time. :)

[uninformed]

John,
'Fenders dont run the A/C thermostats on the elbow such as discos.
Also really Phil is not running his diesel at 97 he is running the outside surface of the alloy head at 97... as mentioned if the OEM gauge is at 3/4 the actual coolant water temp is more like 110 maybe more.

Cooling system needs some loving IME

S

And a hole cut in the left guard :D

[roverrescue]

On my TD5 when the engine Guardian reads 83deg (fitted on the coolant pipe entering the head) the Nanocom is reading 87deg at the coolant sensor.

Ned, I assume those readings are when temps are stabilized about the thermostat temperature.

Now run the water temp quickly up to 115 and see how long the head bolt temp takes to reach 115
If your cooling system gets the funk one day you can test it. Especially if the water temp then drops as soon as you get over the hill, the actual head temp will not reach the peak that the coolant has.

S

[philandmickey]

Thanks to everyone for all the info and advice.

Sounds like the cooling system needs further looking at, I'm still trying to work out how to test the Viscous fan? I guess there is not a lot one can test with the water pump just replace it?

We are going on a trip to the Grampians and posible High country in a few days for 10 days so I guess it will get a good test then!

Will keep you posted of developments.

Have a jolly good Christmas and very happy New Year

Phil

[Bush65]

Test the viscous coupling with a paint brush, not something like your hand, which will hurt (worse than that) or something less forgiving, which will damage the fan.

At temperature below the opening of the thermatic valve, or if the coupling is faulty, you will be able to stop the fan by holding the bristle of the paint brush against the spinning blade.

With a viscous coupling in good order, when the thermatic valve opens and the silicon has effectively "locked" the coupling the brush can't prevent the blade spinning.

Some viscous couplings can be repaired by re-filling with silicon.

[Bushie]

Or like my old Rangie - drill a hole through and drop a bolt into it !!! -worked fine for the next 17 years :)


Martyn

[Kevin B]

Test the viscous coupling with a paint brush, not something like your hand, which will hurt (worse than that) or something less forgiving, which will damage the fan.

At temperature below the opening of the thermatic valve, or if the coupling is faulty, you will be able to stop the fan by holding the bristle of the paint brush against the spinning blade.

With a viscous coupling in good order, when the thermatic valve opens and the silicon has effectively "locked" the coupling the brush can't prevent the blade spinning.

Some viscous couplings can be repaired by re-filling with silicon.

I just checked mine, when I start cold the fan cannot be stopped with a paintbrush or even rolled uo newspaper but after it reaches normal opp temp tge fan can easily be stopped with a paintbrush when I let it go it takes s bit to start spinning again, does that mean mine is RS?

1993 Discovery 1 3.5l
2" Lift, Cranked HD Trailing Arms
31" Maxxis Mudders
Tons of Radios, Tons of Spotties

[philandmickey]

Hi
I thought I would give you a bit if an update of my cooling issues.
I did the paint brush test on the fan and found at normal temp - 82, I could stop the fan and then spin it backwards while the engine was running.

So I removed it further tested it by pouring boiling water over it while spinning it by hand and again no lock up.

As it was Christmas I did not think I would be able find one locally so decided to lock it. The way I did this was to make up small L shape brackets that the fan bolts went through then welded the bracket to the centre nut.
Once I fitted it the next problem occurred.
As the fan was locked I could not keep it tight on the shaft, however much I tried to tighten it, it came loose!
Back to the drawing board!
Found a company in NSW who had one they over nighted it to me I fitted it today and so far it seems a million times better than the old one.
We leave in the morning for 10 days away so hopefully all will be good.
Further news as it happens.
Thanks again for all the advice
Have a fantastic new year
Cheers
Phil

[slug_burner]

I just checked mine, when I start cold the fan cannot be stopped with a paintbrush or even rolled uo newspaper but after it reaches normal opp temp tge fan can easily be stopped with a paintbrush when I let it go it takes s bit to start spinning again, does that mean mine is RS?

1993 Discovery 1 3.5l
2" Lift, Cranked HD Trailing Arms
31" Maxxis Mudders
Tons of Radios, Tons of Spotties

Kevin B,

The fan normally roars at start up, ie, it is engaged and turns as you have described, can't be stopped by a brush.

After a short period the fan disengages after it redistributes the silicone oil, at this stage you car is not up to temperature so it is ok that it does not engage and you can stop it with a brush.

After a few minutes if your thermostat is working the cooling system will get up to temperature. You then have to get more heat into it before the fan will engage again. The fan will engage for short periods as it pulls the temperature down fairly quickly.

I would not be throwing the fan center out just yet. If it engages on start up it has oil in it. It is just a matter of if you have enough. Unless you are having overheating issues I would get a few more checks done before thinking about changing it.

On really hot days when you are stationary with the A/C on you will hear the fan cycling on and off, it roars when it is engaged due to the huge volume of air it moves. You may have to open the window a bit to hear it if you car is well sound insulated. If the fan does not cycle under these conditions then you are likely to be experiencing overheating and it is time to check the rest of the cooling system and then maybe you will need to get a new thermostatic clutch fan.

Don't replace it with an electric fan, they cannot move the amount of air an engine driven fan can. As the thermostatic clutch fan idles when the system is running cool enough they don't waste power when your cruising along the highway. At cruising speed the air forced through the radiator by the vehicles motion is enough to keep the system at thermostat temperature and the clutch fan will not engage.

[philandmickey]

Hi
I have noticed I never followed up on the outcome of this problem and as I find it frustrating when, a thread never comes to a conclusion, thought I would conclude it.

The new viscous fan arrived and there was distctive difference with the new one. You can hear it roar on start up and the engine is running a lot cooler now under load.

So all is good.
Thank you for all the assistance.
Phil

[PAT303]

Phil,lastly don't drive a Tdi with your foot to the floor when under load,you'll cook it,find a gear and speed it likes without labouring it and it'll be happy.I think too many people try and keep up with traffic when loaded and that causes most of the Tdi's supposed cooling issue's,with 3T on board cruise at 100 or so and go down a gear when she starts labouring and you will find that your speed might be low but your average road speed will stay quite reasonable over the trip.I'd do a valve set and tune before your trip also. Pat

[philandmickey]

Thanks Pat
I try to avoid foot to the floor due to the amount of smoke the car produces.
Shal avoid it even more so now.
Car is running a lot better since I changed all the lash caps, half of which were completly worn through.
Cheers

[PAT303]

What color smoke?. Pat

[philandmickey]

Black
Definitely diesel.
It's been looked at by a land rover specialist, who says its normal.
But I'm going to let a diesel specialist with a rolling road have a look and see what they think.

Leaving a cloud of smoke behind me every time I pull away from lights seems a bit excessive!