Water Running Temp and Fans...

[chris1972]

Just a quickie, but this is the first really mild day where I've been driving the car in normal temps and it seems to be running hot.

During the cold spells, it was running around the 50-60deg mark. The fans tended to cut in around 80 (or just before) and quickly reduced the temperature. I've been doing a little town driving today and the weather is a bit milder. Fine on a run (just under 70 degrees) however, the temperature quickly rises in town and I'm struggling getting it down again. Even when the fans kicked in, it seemed to maintain a constant late 70's early 80's temp. I'll check the coolant level tomorrow morning, but I cannot see any obvious leaks.

This evening, I left it to idle on my drive to check the temp. The fans cut in around 80 degrees, then switched off and the temp continued to climb towards 90, which is when I turned the engine off. I have the fan override switch, but wondered what would cause this?

Any ideas?

[Colin RedGriff]

I would suspect low coolant level first, also worth checking you've not got any obstructions blocking the air flow through the radiator

[Bassfiend]

That all sounds reasonably normal ... the water temperature sender is generally acknowledged to be in a pretty poor location and suffers hugely from heat soak, taking ages to come back down again.

Were the fans cycling on and off?

Phil

[WOO5IE]

Sounds normal.
Remember the temp guage does not reflect the engine temp exactly only what is normal for the car .
can vary a lot depending on outside temp

[hodgo]

I agree with bassfiend. Mine was overheating before Xmas and turned out to simply be lack of coolant. Expansion tank ok but header tank low. Top up and heater matrix on hot, run engine and back ok. 

Do some reading on the coolant temp sensor too. It's In a poor place to accurately gauge temperature. my fans first went on at 80, small cooling and then rose to 90 until pretty much staying there. I was worried like you. A small part over 90 but not much before fans came on to reduce back. Hooking up my rovergauge software showed otter switch operating perfectly, fans on at 97 and off at 92...consistently. Now I know that the readings to the sensors and ecu are working Im comfortable with my cars characteristics. On the move it's anywhere between 70 and 80 but it does rise fairly quickly. For info I am running my main cat and soon to decat so am interested how this will affect running temps. Also, I'm changing my thermostat for a 74 opener and otter Switch to 92/87 - easy jobs for better cooling confidence. Oh, and also check the concentration of my antifreeze. 

[StarmistBlue400]

Sounds the same as mine. I don't think there is anything to worry about.

[TV8]

Hi Chris, I would get the Roverguage lead/software or if you are near Bromley, you can connect up mine and that will tell what is going on temperature wise to put your mind at rest.

[Bassfiend]

I've actually got a new and correct temperature sender for my early "ETB" gauges plus an adapter to allow it to be installed in the Range Rover sensor location - just waiting for decent weather to be able to actually fit it!

(This is probably the thing that I'm looking forward to fitting most out of the pile of bits I need to attend to in the corner of my living room!)

There's a mod that you can do to drive the gauge from the Range Rover sender but as far as I can tell the Range Rover sender is *NOT* the correct resistance curve for the gauges, and so, although with a variable resistor you can get it to indicate the right temperature at one point in the gauge range, it does get progressively further "out" the further above or below the calibrated temperature you go.

[chris1972]

Thanks for the advice everyone, very much appreciated. I had been doing a lot of stop/ start driving, parking up for ten minutes etc, however, I'm still getting used to the characteristics of my car at the moment. I'm used to seeing a temp gauge in my diesel that never moves, so watching these dials go up and down has become a bit of a past time whilst driving!

I'll also check out the Roverguage software. Thanks for the offer Graham. I travel to London fairly frequently, so if I'm heading up your way I'll drop you an e-mail and see if we can hook up for a brew. First thing tomorrow, coolant check!

If there's one thing that I've learnt is that these cars get hot very quickly. Is there anywhere that these cars are known for coolant leaks that I can check? I've had a good look under the bonnet, but cannot see anything.

Cheers
Chris

[Mr Supercharged]

They can leak coolant in lots of places, classics are radiator matrix, (when I bought mine it was actually leaking on the back where the fan cowls had fretted through!). Other areas are leaking hoses where the jubilee clips have not been tightened up, leaking heater matrix, failed head gasket or worst of all a slipped block liner which causes over pressurisation of the coolant system. This last one is most easily noticed by coolant leaks around the expansion tank filler cap after a long run but this could also be caused by having this tank over full of coolant. Typically, it should be about 1/3 to half full ish.....

[chris1972]

Okay, I've checked the coolant and it isn't particularly low,has a green and sludgy scum in both tanks, so I think it's time for a drain, flush and new coolant. It is cold this morning, so I expect some of the sludge to solidify a little in the cold, but there seems to be quite a lot. I've prodded a bar into the main tank and there's plenty of blue coolant in there.

Main coolant tank:


Expansion tank:

[portzi]

have different colours or brands of colant been mixed as I have only seen this once before and it turned into a sludge like your pictures , hope you get it sorted.

Mark

[JFReturns]

Yuck! Time for a coolant flush...

[Sardonicus]

JFReturns said:

Yuck! Time for a coolant flush...

This.

[GasMunkey]

When I flush my system out, I pull a couple of hose's off and attach the garden hose to that and wait for it to become clear out the other end

[TJC46]

TV8 said:

Hi Chris, I would get the Roverguage lead/software or if you are near Bromley, you can connect up mine and that will tell what is going on temperature wise to put your mind at rest.

Sorry to hijack this thread somewhat but could you please give more details on Rovergauge/lead software.

Excuse my ignorance, but is this a way of linking a laptop[plus relevant software] up to the standard ECU.

If so where is the software/lead available from, and at what cost.Thanks Tom.

[TV8]

TJC46 said:

TV8 said:

Hi Chris, I would get the Roverguage lead/software or if you are near Bromley, you can connect up mine and that will tell what is going on temperature wise to put your mind at rest.

Sorry to hijack this thread somewhat but could you please give more details on Rovergauge/lead software.

Excuse my ignorance, but is this a way of linking a laptop[plus relevant software] up to the standard ECU.

If so where is the software/lead available from, and at what cost.Thanks Tom.

This is the part. Mark is a regular on here.
http://classifieds.pistonheads.com/classifieds/par...

[Bassfiend]

Sardonicus said:

JFReturns said:

Yuck! Time for a coolant flush...

This.

Absolutely - that looks pretty manky!!!

[chris1972]

Which hoses do I remove to flush the system? Do I have to wait for the thermostat to operate a couple of times to allow the clean coolant etc to circulate?

Anybody got a pic of the hoses I need to remove?

[Bassfiend]

Just popping the bottom hose off should get you pretty much a complete drain (there'll still be some remains in the heater matrix) and yes, you really do need to get the thermostat to open to get a decent flush.

Of course you could pop the thermostat out ...

Phil