When traveling in the middle of nowhere it might be good to carry a spares kit. On belts and tensioners, etc. I saved my old ones for sparts.. Just saying..

I don't think your engine could tell the difference between freezing and hot weather as it operates in the same temperature range. It will overheat, let's say by a frozen radiator, failed water pump, or broken belt.

Let's say you are stranded with a Water Pump failure.. Maybe you could go 5 minutes, and wait 10, or just wait for rescue.. A good question though.

 

I expect even five minutes in arctic weather is too long and you will have destroyed your engine.

I had a rear frost plug pop out of my GM 350 a few years back; that was for the most part, no water at all in the lower parts of the engine, and the engine was hence destroyed, not seized but effectively destroyed.

Neither the temperature gauge nor the radiator low water level light indicated anything as the rad remained full of water due to some sort of air lock and the temp gauge sensor only works when it is immersed in water.

I actually saw the water discharge in my rear view mirror but thought it was smoke burning off my new muffler just installed.

It was maybe five minutes between when I saw something in my mirror and steam was coming out around my hood - and that was Made in USA cast iron, not exotic foreign stuff.

In other words, spend time and money on preventive maintenance - that is cheap compared to just drive it til it stops.

With preventive maintenance, you tend to build a spares kit kind of for free and you do the fix at your leisure, not out in the cold and wet on the side of the interstate with your wife fuming and the kids crying.

 

Gents, I do have a spares kit, including the belts we are talking about.

Also, I don't mean to be argumentative at all, just want a good discussion...but your responses have drifted off topic. Let's talk about the specific case of a fan belt on the specific vehicle Land Rover LR3.

The belt only drives the fan, right? Not the water pump. So focusing the discussion on only the belt that drives the fan, what are the downstream effects of that breaking and how long could the vehicle be safetly operated in cold weather?

 

houm, nobody here is being argumentative or trying to start anything. Are you looking for scientific theory, or opinion and conjecture here.

There is one way to find out, take the belt off and drive it. It is not cold enough here to consider it.

 

Now I understand the question- silly me.

You are asking how the 3 might react if it were like the new GM pickups where the belt driven viscous fan has been replaced with a couple of radiator mounted electric fans, like on a Honda. I must say my first reaction when I lifted the hood of a new GMC pickup and saw a north south engine without a belt driven fan was "it sure is empty in here".

The 3 uses what is called an electroviscous fan controlled from the engine computer. The clutch portion can be locked up to have the fan run as a conventional viscous fan or unlocked, (as if the belt is gone or it was just an electric fan), and the fan freewheels until the engine computer says to reengage, or anywhere in between.

You might notice that action on a cold morning at first start up when the fan noise sounds very loud, and then perhaps 30 seconds to a minute later the fan noise drops off - that is the initially locked clutch depowers and the fan then freewheels as if there is no belt drive.

The locked clutch instruction results from cold start emission requirements and is an attempt to put a bit of a load on the engine.

More specifically, the temperature of the cooling system is monitored by the Engine Control Module via the Engine Coolant Temperature (ECT) sensor located in the cylinder head. The ECM uses signals from this sensor to control the cooling fan operation and adjust fuelling according to engine temperature.

The ECM controls an electronically controlled viscous coupled fan to provide engine cooling. The ECM supplies the fan with a PWM signal that controls the amount of slippage of the fan, thus providing the correct amount of cooling fan speed and airflow. The EMS uses a Hall Effect sensor to determine the fan speed.

The ECM varies the duty cycle of the PWM signal between 0 and 100% to vary the fan speed. If the PWM signal is outside the 0 to 100% range, the cooling fan module interprets the signal as an open or short circuit
and runs the fans at maximum speed to ensure the engine and gearbox do not overheat.

The ECM operates the fan in response to inputs from the ECT sensor, the transmission oil temperature sensor, the A/C switch and the A/C pressure sensor.

The speed of the cooling fan is also influenced by vehicle road speed. The ECM adjusts the speed of the cooling fans, to compensate for the ram effect of vehicle speed, using the Controller Area Network (CAN) road speed signal received from the Anti-lock Braking System (ABS) module.

The above two paragraphs are the interesting ones. Note that the temperature sensor paragraph eludes the to the fact that the round temperature gauge on the dash is not solely an engine coolant gauge but also is subject to engine oil temperature; also that the clutch control for the fan in influenced by cabin temperature.

In summary, all this means is that if the fan belt is missing, a lot of seemingly unrelated lights could appear on the dash, or perhaps worse, none at all - and yes, on a cold day, if some other system did not throw the 3 into safe mode, you might just be able to drive all day.

My guess would be that on a real cold day and level road surfaces, the fan might be just along for the ride; also that as long as the fan circuit is plugged in, the systems may not notice the fan belt is missing.

It was a good question I guess - really got me to thinking.

 

@unseenone: only person I was accusing of being argumentative was myself! I just didn't want you guys to think I was being a douche....

...what I really want to know, is mostly what bbyer touched on. Is it game over if that fan belt breaks? Sounds like the answer is "hmmm....maybe." I'd definitely want to keep an eye on that temperature gauge.

I will stock the belt in my spares kit plus the clutch holder and wrench in my tool kit....and hope that it doesn't happen. I had the guys at LR Seattle evaluate the belt a few weeks ago and they said it looked good; they didn't suggest changing it even though they know where I'm going next month! (Whitehorse)

 

So you are going back to the Great White North - again, if I recall correctly. The trouble is Northern BC and the Yukon are a bit hilly - the hint as you no doubt know is the mountains on either side that you will be driving thru. You will need the good headlights that our 3's have as you can drive hours without seeing any thing but snow and the odd moose. Even seeing an RCMP 4x4 police truck is a comforting feeling. These days, they are driving either winch equipped Ford F-350 crewcabs or Tahoe's.

I think this is where that question of tensioners and pulley bearings comes into play. The good news is that there is a lot of Ford in our 3's and once you pass Vancouver BC, the next closest dealer north of you will be in Iceland.

I think the NAPA guys can cross the LR tensioner to a Ford Fusion belt tensioner or some other mini car Ford like that. Regardless, I will not be fussy or too proud to go crawling in to the Ford guys. At Christmas, I drive down to ski area near Fernie BC. Best of all, there is a local Ford dealer - closed of course due to Christmas, but it makes me feel a bit less apprehensive anyway.

In short, the water pump pulley belt does matter - Ford does not stock the petrol 4.4L V8 Jaguar engines, short block or otherwise, that is for certain. They do however have the 4L V6 and its bits and it only has one serpentine belt driving all.

When you are driving in cold weather, the first hint of a cooling system problem in the winter is not the temperature gauge but either your heater starts to work really well or not at all. Either one is not good.

 

Bruce:

A few things: I have not gone on that trip yet. I planned it for last year and had to move it to 2014; so the inaugral trip is in March this year. I have the belt; I won't need to source a part. ...and what do you mean by water pump pulley belt? Were you referencing the Ford in that sentence?

I guess I'm just being paranoid about my secondary serpentine belt. I replaced the primary a few years back and didn't do the secondary for some unknown reason and now I'm worried for probably no reason. Dealer techs said it looked fine.

???

I just wanted a little comfort knowing that it ONLY runs the fan and I'd be travelling in an area where folks use radiator covers ("muffs") presumably to keep the cold air from making their coolant too COLD...so who the hell needs a fan, right?

 

With the V8, the long belt is what is called the primary serpentine belt and it operates everything but the fan. The primary belt operates the alternator, air compressor, power steering and water pump.

Yes, you are correct about covering over the grill/radiator area with cardboard and or custom made quilted covers that seem to be the norm, but that is with American pickups, not necessarily with that exotic foreign stuff.

For what it is worth, I do not have a grill cover for my 3. If it were a diesel, probably I would, but even then I would be cautious. The problem with these new vehicles is one does not want to be closing off cooling of the transmission oil. Everything is more complicated now so what worked in the past or was normal practice does not necessarily work any longer.

The reason the thermostat is so complicated and there are so many little hoses is to allow controlled water bypass flow to various portions of the engine or just to the heaters with other circuits shut down. In other words, all this PWM stuff is supposed to do what a piece of cardboard did before and then undo it as well.

If you ever wondered why the nice piece of weather stripping surrounding the top of the engine compartment is there, well it is not for looks. It was included to provide a combination of air and water control in the engine compartment. The idea is that when fording creeks, if you travel fast enough and do not stop, the engine compartment will not get wet as it remains sort of pressurized due to the sealing effect of the rubber against the underside of the bonnet. To some degree, the same holds true with air, be it hot air in the desert or cold air in the winter. The operation of the fan, or not, to some degree controls the pressurization.

Yes for water crossings, you do see canvas set in front of the grill but that is more often seen in Series Land Rovers and Land Cruisers.

 

Yes, I'm aware of the belts. That's my whole thing....I just replaced the primary; not the secondary. That's why my line of questioning pertains to the fan and nothing else.

Oh, and if the radiator muff is not such a good idea for an LR3, someone should've told me that before I dropped over $100 (incl. shipping) on a version that is made specifically for the D3; from the U.K. !!!