Viscous fan ....... removing it for winter

Just removed the fan from my 300 Tdi today, only covered 30 or so miles so far. No real noticeable differences, perhaps slightly quicker warm up. Thinking about blanking part of the radiator as well to see if this has any effect.

arienol said:

Thinking about blanking part of the radiator as well to see if this has any effect.

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Ooh, could be tempting fate there

A word of caution about relying on LR Disco temperature gauges – they are designed by LR not to read engine coolant temperature accurately, as follows.
The gauges read on an analogue basis upto about 40C and then settle to a “normal” position and do not register again until about 90C. ie between 40C and 90C approx the gauge does not move, intentionally.
At about 90C the gauge again responds to changes in coolant temperature and moves up towards the red, or as some people call it “the too late position”. At this point you’ve probably overheated the engine.
This explains why coolant temperature gauges in Discos settle at a particular level and never seem to move. In fact what they are doing is indicating the coolant temperature has reached about 40C. Depending on operating conditions however the engine coolant temperature continues to rise until the thermostat opens at 88C and can in fact exceed this temperature. All the time the temperature gauge is reading “normal”
Apparently this is done by LR so as not to worry Disco drivers as a correctly reading gauge would indicate the true widely varying temperature the engine coolant operates at.
If you want to see accurately what is happening to engine coolant temperature fit an additional temperature by someone like VDO that does accurately indicate coolant temperature.
This is particularly relevant to people who remove viscous fans and also those who have ac fitted, including myself.
Beware in hot weather, the temperature gauge may be reading “normal” but in reality it is only indicating the coolant is above 40C – it could be anything.
You will only find out if the gauge suddenly starts to move towards red.
Obviously there are a lot of 200 and 300 Discos operating without viscous fans without any problems but if the weather gets hot or the car is working hard, better to be cautious than overheat the engine.
None of this is a problem of course if you fit an electric fan, or a proper temperature gauge.

wow. where'd you find that out?

Interesting stuff, thanks

nicedayforit said:

If you want to see accurately what is happening to engine coolant temperature fit an additional temperature by someone like VDO that does accurately indicate coolant temperature.

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when i first started putting 200s in old 90/110s i ran a few round with a multi probe digital temp monitor hooked up just to make sure

the standard temp gauge can never be used for an accurate reading, simply because it's got so few graduations but it's certainly VERY responsive - not being able to see it move due to it being steamed up is more of a problem

nicedayforit said:

If you want to see accurately what is happening to engine coolant temperature fit an additional temperature by someone like VDO that does accurately indicate coolant temperature.

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i'd quite like to know where your info comes from, I've fitted a few VDOs, and have driven a good few on test and none of them vary much once warmed up

Ok, so i took her out in the snow, first time this morning

Got to work and probed the old girl with an infra-red thermometer. I had to switch her off while i dashed in and got the tool so these temps are after about 1-2mins of standing.

Outside temp - 0c, snowing.
Turbo housing - 170c
Turbo top hose - 7c
Rad top hose - 67c
Cyl head (left side) - 82c
Block - 68c
Stat housing - 75c

I couldnt find any engine part over 82c apart from the turbo itself so it appears that they do stay cool. However, this is not good enough for my peice of mind so i'll probably refit the fan until i can get a leccy one in there, i'll fit an override switch and an indicator lamp on the dash too maybe. Driving with no fan is just too uncomfortable for me, i panic everytime the traffic stops moving so its no fun. Thats just me though

for what its worth i would just keep the fan off and keep it in the back they only take seconds to re fit it isn't as though you have no fan just remember to keep the fan with you at all times.

graham
__________________
98 d1 300 tdi auto.

Do you need the special tool to get the fan off or can you do it using something else?

On my 300tdi, i can use a 32mm spanner or the proper tool, there is just enough room to get a slim spanner in there. Dont forget its a left-hand thread so undoes clockwise.

davek0974 said:

Ok, so i took her out in the snow, first time this morning

Got to work and probed the old girl with an infra-red thermometer. I had to switch her off while i dashed in and got the tool so these temps are after about 1-2mins of standing.

Outside temp - 0c, snowing.
Turbo housing - 170c
Turbo top hose - 7c
Rad top hose - 67c
Cyl head (left side) - 82c
Block - 68c
Stat housing - 75c

I couldnt find any engine part over 82c apart from the turbo itself so it appears that they do stay cool. However, this is not good enough for my peice of mind so i'll probably refit the fan until i can get a leccy one in there, i'll fit an override switch and an indicator lamp on the dash too maybe. Driving with no fan is just too uncomfortable for me, i panic everytime the traffic stops moving so its no fun. Thats just me though

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Mine's been off for over a year now,and if driven hard in summer,would almost make it to halfway,but as soon as you get caught in traffic on tickover the gauge actually drops-don't think it is possible for 300tdi to reach normal temp on just tick over-thinking about blanking the rad a bit in this cold weather-but that to me with no fan seems risky

biolandy said:

Mine's been off for over a year now,and if driven hard in summer,would almost make it to halfway,but as soon as you get caught in traffic on tickover the gauge actually drops-don't think it is possible for 300tdi to reach normal temp on just tick over-thinking about blanking the rad a bit in this cold weather-but that to me with no fan seems risky

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I guess its all down to how much bottle the driver has

I would be happier with a digital temp display that actually showed me what was going on in there, much happier.

I was surprised how low the turbo temp was, is that normal? I thought these things ran sh1t hot?

I'm a bit of a control freak i guess, i 'need' to know whats going on when i start altering things from standard. I had the same thing when i fitted a kenlowe to my old S3 109, waiting for the guage to rise when setting the 'stat knob was a bit nervy, but it worked ok after.

Just me i guess, i'll leaver her off a bit longer but TBH, i cant see much difference.

Just an update, after the drive home i left her running and check around the engine again..

Outside temp - 0c, snowing still.
Turbo housing - 165c
Turbo top hose - 14c
Rad top hose - 62c
Cyl head (left side) - 80c
Block - 69c
Stat housing - 75c

Looking at this it appears the stat was closed (or at least partially) as the top hose was cooler than the stat housing, so definately not running hot.

I was surprised to see the turbo temp dropping pretty fast too it was 179c on first check and last check was 159c, which kind of backs up the advice i was once given to always wait a short while before switching off to allow a turbo to cool so it didnt cook the oil on the bearing.

I would be lot happier if the temp gauge behaved as a gauge and not just a "cold - normal - oh fu*K" indicator

Plus, without the fan, i can hear the viscuous hub bearing grumbling