TD5 viscous v electric, who's done it. what are the options?

haha, I think I may have opened a can of worms.

Thanks for the input everyone.

I've emailed the company that you recommended Tombie, no reply back yet about if Dave's low coolant alarm screw will fit into the new hose. maybe I should send dave a message as well? will he know the product? the low coolant alarm has been on my shopping list since I bought the car a couple months ago. I want to have it. I've had a couple cars overheat and i'm not getting bitten again. The first car was my own fault, the second was manufacturers (arguably mine as well, TBH I wasn't watching the temp gauge like a hawk on that trip like I should have been but I doubt many people watch it that closely) but if i'd had a low coolant alarm on the second the damage would have been far less.

Quote:

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Originally Posted by Tombie

www.samcosport.com/manufacturer/land-rover/

Part TB-3051

Not cheap but you’ll only do it once!

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hey mate just thought I'd quote you on this so that you can see the above reply and if you know the answers

cheers

So the original size bleed screw is different to the samco version for anyone that’s interested. Samco have a 5mm thread

Just spotted this notification

Seems you found your answer.

I've just found this thread, i can tell that i tried 3 kind of e-fans on my td5 and non of them had enough guts at 35*C... one was a Revotec sold in UK as dedicated for the Td5, this was the worst but the most expensive, got the ECT to 110 in no time then i tried a german universal but stronger fan with the same result and in the end a big russian 600W fan which was the best but still not enough to keep the ECT under 100 like the viscous does.... i strongly discourage everyone against this mod on a Td5 where the ambient temps can rise above 30*C.... just wasted money and energy IMO.

Sierrafery with experience! Did you keep a photo of the install by any chance? Was it a DII?

Just looked at the revotech offerings, one flat blade fan (16 inch?) on a frame with holes in it. Looks like it would pull some of its air from the engine bay! Absolute rubbish!

I reckon another issue to consider is pressure build up and lack of natural flow through the engine bay. A D2 engine bay looks more restrictive than a Defenders, in either case a viscous fan is more likely to overcome those restrictions.

So if it can be done on a D2 TD5, it would need maximum fan coverage of the core, on a proper sealed shroud, twin speed fan(s) up to around 400w, AND perhaps some extra vents out of the engine bay in low pressure zones to facilitate flow through the engine bay.

So yeah, for the sensible this all translates to: too much mod/expense/time for very little if any gain.

But if you had to cool a TD5 without the viscous, it could probably be done.

When the electric fans on our D1 300Tdi died on the Telegraph Track, we were able to remove the driving lights to just get enough airflow so the viscous fan could keep the engine cool enough to drive it home. Without the viscous fan, it would have been an expensive tow job. So I recommend you keep the viscous.
Interestingly, British OffRoad fitted a used set of Ford Falcon fans to our D1, which worked fine. I'm not sure of your situation, but might that be an option for you?

Mick, are you talking about the ac condender fans? They only come on with AC or if your motor is overheating. Basically without AC on, those fans shouldnt be required. Was your radiator blocked up by any chance?

Manic - and you don’t think I’ve had these experiences?
Tried and tested these types of device to see what happens?

If I told you sticking your hand in front of an oxy flame would burn you would you need to experience it to understand that it would hurt?

There are calculations that can be done to confirm the cooling air movement required and the pull or push efficiency of fans. Knowing these can provide all the answers - which can then be verified by a real world test.

Simply - a fully shrouded eFan is good for about 2500cfm at full song. A correctly shrouded driven fan is good for that at just on idle and goes up to 5000cfm at full speed.

The other myth is engine warm up time - this is the thermostats task, the only marginal cooling a driven fan is doing is a bit of air across the motor.

And whilst on that - guess what happens to under bonnet temps with efans and no driven fan; it’s higher!
This was tested on one of my vehicles with thermocouples in the engine bay.

Quote:

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Originally Posted by DiscoMick

When the electric fans on our D1 300Tdi died on the Telegraph Track, we were able to remove the driving lights to just get enough airflow so the viscous fan could keep the engine cool enough to drive it home. Without the viscous fan, it would have been an expensive tow job. So I recommend you keep the viscous.
Interestingly, British OffRoad fitted a used set of Ford Falcon fans to our D1, which worked fine. I'm not sure of your situation, but might that be an option for you?

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As mentioned earlier - low BMEP engines take less airflow through a decent radiator to dissipate thermal load.