Peak water temperature
Discussion
Recent Sagaris owner and still getting used to it's quirks and operating characteristics.
From what I've read (lots of threads/comments) the cooling fans kick in separately, According to Graham Varley 91-92° for near side and then 96-98° for the other, and mine are certainly running independently.
I've also read that the temperature that they actually kick in probably doesn't have a direct correlation to the temp thats given on the dash apart from some sort of offset between what it reads and what it actually is.
However (and there's always one isn't there) - what temperature should I happen to see on the dash that would make me think - stop the engine it's getting too hot. I'm used to vehicles with gauges and you can always guess when it's getting too hot as it nudges towards the red.
Chatting to a straight six owner recently he was saying - I shouldn't let it get above 95° which seems rather low when the second fan hasn't had a chance to cut in..
Looking at the historical display I see it's been up to 105° (but then again it also says it's been to 226MPH).
So the question is - at what temperature would you stop the engine as it's getting too hot ?
Oh and is there a high temp alarm on the dash (if so what does it kick in at ?)
From what I've read (lots of threads/comments) the cooling fans kick in separately, According to Graham Varley 91-92° for near side and then 96-98° for the other, and mine are certainly running independently.
I've also read that the temperature that they actually kick in probably doesn't have a direct correlation to the temp thats given on the dash apart from some sort of offset between what it reads and what it actually is.
However (and there's always one isn't there) - what temperature should I happen to see on the dash that would make me think - stop the engine it's getting too hot. I'm used to vehicles with gauges and you can always guess when it's getting too hot as it nudges towards the red.
Chatting to a straight six owner recently he was saying - I shouldn't let it get above 95° which seems rather low when the second fan hasn't had a chance to cut in..
Looking at the historical display I see it's been up to 105° (but then again it also says it's been to 226MPH).
So the question is - at what temperature would you stop the engine as it's getting too hot ?
Oh and is there a high temp alarm on the dash (if so what does it kick in at ?)
Interesting - have you tried Water Wetter to help keep get the heat transferred away quicker ?
A mate of mine puts it in his desert race car in the UAE which aids the cooling.
http://www.redlineoil.com/product.aspx?pid=74&...
A mate of mine puts it in his desert race car in the UAE which aids the cooling.
http://www.redlineoil.com/product.aspx?pid=74&...
I'd say "always keep it below 95°C" is rubbish. Part of the answer you already gave.
During hot summer days in static traffic I rarely get 100°C. Blip the engine and it should go down a bit (higher water pump throughput).
Since it's not pure water and you have overpressure of up to 1.5bars (both up the boiling point) the cooling fluid will not boil at 100°C as pure water would. You can read on the internet, that 115°C to 130°C would be the boiling point depending on the cooling system. On the other hand I would think, that local boiling can occur on hot spots some degrees earlier than that.
I have no first hand experience with constant higher temps than 105°C in static traffic. If I had 105°C during normal driving, I would think that something must be wrong with the cooling system. So would try bleeding first, since air in the system prevents a good heat transfer.
If my dash reading would reach constant 110°C and more air flow (both fans on, normal driving) and higher throughput of coolant (revs) would not bring down the temps, I'd definately kill the engine for sure.
Is there a high temp warning? I never heard of one being implemented into the system. Could be wrong though. :-)
During hot summer days in static traffic I rarely get 100°C. Blip the engine and it should go down a bit (higher water pump throughput).
Since it's not pure water and you have overpressure of up to 1.5bars (both up the boiling point) the cooling fluid will not boil at 100°C as pure water would. You can read on the internet, that 115°C to 130°C would be the boiling point depending on the cooling system. On the other hand I would think, that local boiling can occur on hot spots some degrees earlier than that.
I have no first hand experience with constant higher temps than 105°C in static traffic. If I had 105°C during normal driving, I would think that something must be wrong with the cooling system. So would try bleeding first, since air in the system prevents a good heat transfer.
If my dash reading would reach constant 110°C and more air flow (both fans on, normal driving) and higher throughput of coolant (revs) would not bring down the temps, I'd definately kill the engine for sure.
Is there a high temp warning? I never heard of one being implemented into the system. Could be wrong though. :-)
The numbers on the dash are not those that trigger the fans, and neither set of sensors is likely to be all that accurate anyway. If the fans turn on independently and cool the engine until they both turn off, all is basically working.
Normally I never saw over 98ºC unless the air conditioning was on (it compromises the air flow to the main radiator in the T350), and I would turn the air con off if engine temps went over 100ºC.
Only once I saw 105ºC, I turned the air con off and the heaters to full on to get the engine temp down, which worked. Sure enough, teeny hole in the rad. Replaced radiator, and all back to normal.
tl;dr - 105ºC
Normally I never saw over 98ºC unless the air conditioning was on (it compromises the air flow to the main radiator in the T350), and I would turn the air con off if engine temps went over 100ºC.
Only once I saw 105ºC, I turned the air con off and the heaters to full on to get the engine temp down, which worked. Sure enough, teeny hole in the rad. Replaced radiator, and all back to normal.
tl;dr - 105ºC
grumbledoak said:
The numbers on the dash are not those that trigger the fans, and neither set of sensors is likely to be all that accurate anyway. If the fans turn on independently and cool the engine until they both turn off, all is basically working.
Normally I never saw over 98ºC unless the air conditioning was on (it compromises the air flow to the main radiator in the T350), and I would turn the air con off if engine temps went over 100ºC.
Only once I saw 105ºC, I turned the air con off and the heaters to full on to get the engine temp down, which worked. Sure enough, teeny hole in the rad. Replaced radiator, and all back to normal.
tl;dr - 105ºC
Good points made.Normally I never saw over 98ºC unless the air conditioning was on (it compromises the air flow to the main radiator in the T350), and I would turn the air con off if engine temps went over 100ºC.
Only once I saw 105ºC, I turned the air con off and the heaters to full on to get the engine temp down, which worked. Sure enough, teeny hole in the rad. Replaced radiator, and all back to normal.
tl;dr - 105ºC
I compared the values from the dash and the software readout. I had a difference of 1-3°C, so not much. Hysteresis of both sensors is a bit different.
Might be different if these sensors/cables age.
Indeed A/C was on when I had 105°C. So did both: Turn A/C off, blip the loudpedal.
Replaced my rad last year. Had tiny hole(s) at the welds of the side rad tanks due of constricted installation of the rad (stress-cracking at welds). Coolant loss was minimal (few drops per run, but steady and was getting more in amount through last summer).
Maybe this was also part of the problem.
Usually I too see no more than 98°C in the dash readout while driving on sunny days.
I fitted an Engine speed independent cooling system from Tecomotive three years ago.
I has been faultless, water temp worries are thing of the past and the delayed shutdown is brilliant.
I has been faultless, water temp worries are thing of the past and the delayed shutdown is brilliant.
aide said:
I fitted an Engine speed independent cooling system from Tecomotive three years ago.
I has been faultless, water temp worries are thing of the past and the delayed shutdown is brilliant.
That looks like a worthwhile improvement there! Very clever and for only 160 €, but you need the additional water pump for 386 €...I has been faultless, water temp worries are thing of the past and the delayed shutdown is brilliant.
What are the implications of fitting it? Do you have to do irreversible changes to the cooling system in case you want ro revert back for some reason?
Reliable system in your experience?
RobertoBlanco said:
That looks like a worthwhile improvement there! Very clever and for only 160 €, but you need the additional water pump for 386 €...
What are the implications of fitting it? Do you have to do irreversible changes to the cooling system in case you want ro revert back for some reason?
Reliable system in your experience?
It's great. The water pump is made by Pierberg, who supplied the first electric water pump to be fitted to a production 3 series BMW.What are the implications of fitting it? Do you have to do irreversible changes to the cooling system in case you want ro revert back for some reason?
Reliable system in your experience?
Fitting the pump, in series with the mechanical pump, was straight forward enough, completely reversible and has been 100% reliable. The microcontroller regulates the speed of the electric pump and fans based on an independent water temp feed. It has a delayed shutdown feature. When you turn off the ignition it runs the pump and fans for a minute and then just the pump for a further minute. sitting in traffic, staring at the water temp dial is a thing of the past.
I spent a bit of time, with the really nice guy that designed the microcontroller, changing it to suit my car. We threw away a section of the target tempratures and changed the granularity of the tempratures that could be selected.
aide said:
I fitted an Engine speed independent cooling system from Tecomotive three years ago.
I has been faultless, water temp worries are thing of the past and the delayed shutdown is brilliant.
Interesting! Please tell more I has been faultless, water temp worries are thing of the past and the delayed shutdown is brilliant.
Where does the pump go? Did you fit it?
My dash temp sensor reads 10c or more higher than ecu, the higher the temp the more inaccurate and jumpy it gets, tried new sensor too. Its not good because you don't know when it might be true... if you have a tiny leak somewhere or bad cap then at some point the ecu will match the dash! and the sudden cloud of steam shortly after stopping will surprise you.
I currently know whether the dash is true or not by revving the engine up to ~2.5k... if the temp drops the dash is telling porkies. If not or taking longer to drop, stop, wait, and fill up.
No leaks under the car, or smoke from exhaust. Getting new hoses and rad fitted tomorrow, so hopefully the bi or tri weekly top up is less frequent. Was thinking about putting a variable resistor in there to calibrate the dash...
aide said:
RobertoBlanco said:
That looks like a worthwhile improvement there! Very clever and for only 160 €, but you need the additional water pump for 386 €...
What are the implications of fitting it? Do you have to do irreversible changes to the cooling system in case you want ro revert back for some reason?
Reliable system in your experience?
It's great. The water pump is made by Pierberg, who supplied the first electric water pump to be fitted to a production 3 series BMW.What are the implications of fitting it? Do you have to do irreversible changes to the cooling system in case you want ro revert back for some reason?
Reliable system in your experience?
Fitting the pump, in series with the mechanical pump, was straight forward enough, completely reversible and has been 100% reliable. The microcontroller regulates the speed of the electric pump and fans based on an independent water temp feed. It has a delayed shutdown feature. When you turn off the ignition it runs the pump and fans for a minute and then just the pump for a further minute. sitting in traffic, staring at the water temp dial is a thing of the past.
I spent a bit of time, with the really nice guy that designed the microcontroller, changing it to suit my car. We threw away a section of the target tempratures and changed the granularity of the tempratures that could be selected.
So you didn't disable the mechanical pump then, right? I was under the impression that this might be detrimental to either of the pumps. I read about the booster function, but still not convinced about that. I would think, that you'd have to uninstall the rotor of the old pump to be safe. And this is a bigger surgery i reckon.
Which position did you choose to tie in the new pump? Manual says "behind rad" but this could be difficult, since the oil heat exchanger is in the way more or less.
Do you have pictures you could share with me? Would be highly interested in them. PM me if yu do not want to share them via the forums. Appreciate it.
Sorry to kill you with these questions, but haven't heard of any mod like this done to any TVR before.
RobertoBlanco said:
Cheers for all the info. Sounds great.
So you didn't disable the mechanical pump then, right? I was under the impression that this might be detrimental to either of the pumps. I read about the booster function, but still not convinced about that. I would think, that you'd have to uninstall the rotor of the old pump to be safe. And this is a bigger surgery i reckon.
Which position did you choose to tie in the new pump? Manual says "behind rad" but this could be difficult, since the oil heat exchanger is in the way more or less.
Do you have pictures you could share with me? Would be highly interested in them. PM me if yu do not want to share them via the forums. Appreciate it.
Sorry to kill you with these questions, but haven't heard of any mod like this done to any TVR before.
The original mechanical pump is still in situ.So you didn't disable the mechanical pump then, right? I was under the impression that this might be detrimental to either of the pumps. I read about the booster function, but still not convinced about that. I would think, that you'd have to uninstall the rotor of the old pump to be safe. And this is a bigger surgery i reckon.
Which position did you choose to tie in the new pump? Manual says "behind rad" but this could be difficult, since the oil heat exchanger is in the way more or less.
Do you have pictures you could share with me? Would be highly interested in them. PM me if yu do not want to share them via the forums. Appreciate it.
Sorry to kill you with these questions, but haven't heard of any mod like this done to any TVR before.
There are two completely independent pumps, in the same system, moving coolant around.
We sent emails to the likes of Davis Craig and other respected companies & individuals and decided to keep the original mechanical pump but fit the new pump on the opposite side of the cooling system.
I guess, in one scenario, if one pump is being driven at a constant rate (ie engine speed) and another pump is causing the water flow to fluctuate, there is a possibility that the flow will stress the passive pump.
We fitted it three years ago. Since then we also fitted a speed six oil cooler (I have a 4.5 v8) and it has been perfect.
HTH
Aide
aide said:
I guess, in one scenario, if one pump is being driven at a constant rate (ie engine speed) and another pump is causing the water flow to fluctuate, there is a possibility that the flow will stress the passive pump.
This is what I was aiming at. Ok, you haven't had problems in the last 3 years, fair enough. Still, I would rather disable the mechanical pump to prevent that, I suppose...Sorry to ask again, but no photos you could share showing your setup? I'm not sure I got the positioning of the pump in your engine bay right, which you mentioned. Not too familiar with the V8s and their engine compartment, too.
I believe removing the mechanical pump is an engine out job on a v8.
The new pump is fitted under the F1 panel above the steering rack. Hot water is routed through it to the thermostat. it's pretty simple. And the microcontroller is in the passenger footwell with the ecu. I'll see if I can find a pic somewhere.
The new pump is fitted under the F1 panel above the steering rack. Hot water is routed through it to the thermostat. it's pretty simple. And the microcontroller is in the passenger footwell with the ecu. I'll see if I can find a pic somewhere.
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