Discussion
Morning team, Just quickly everyone goes on about hot start and overheating. should I be worried about over cooling ? my car rarely ever get above 75 in traffic or on a run out. I can leave it idling for 15 mins and it just sits there happy, fans don't cut in. Is this something that I should be worried about ?
h as I use the car every day and the heater just moves around warmish airWell mine
runs around 70 in the current weather, rising to 90 max sat in traffic in summer. It's what my car has always done as I take the absolute gauge reading to be unique to my car. I suspect it under reads a little. I would be concerned if it did something different.
If you still feel it is rumning cold, and you want more winter heat the only option is a blind over the radiator, but be careful you have the ability to adjust should you over heat.
runs around 70 in the current weather, rising to 90 max sat in traffic in summer. It's what my car has always done as I take the absolute gauge reading to be unique to my car. I suspect it under reads a little. I would be concerned if it did something different.
If you still feel it is rumning cold, and you want more winter heat the only option is a blind over the radiator, but be careful you have the ability to adjust should you over heat.
This can be one of the most frightening things, if the temp sensor sits in a steam pocket it will read like that ~ whatever the coolant temp. Personally I hate the sensors that sit on top of the manifold for that very reason, I would always use the ones low in the manifold so that you can be sure they are immersed in coolant to read correctly. Since your fans aren't engaging yours is probably OK from that POV.
More likely that you have a low stat with lots of bypass, which in this weather is likely to just allow enough pre-opening flow &/ early opening partial flow to keep the temps down. It's such a fine line of keeping engines warm in cold weather & allowing cooling to happen early enough in hot weather that I am convinced the only real solution is to fit summer & winter stats ~ rad shrouds may help on the move (ie engine generating heat) but as you've noticed with no air flow there is still enough cooling in zero temps.
More likely that you have a low stat with lots of bypass, which in this weather is likely to just allow enough pre-opening flow &/ early opening partial flow to keep the temps down. It's such a fine line of keeping engines warm in cold weather & allowing cooling to happen early enough in hot weather that I am convinced the only real solution is to fit summer & winter stats ~ rad shrouds may help on the move (ie engine generating heat) but as you've noticed with no air flow there is still enough cooling in zero temps.
Weather looked good yesterday morning so drove the TVR 40 miles to work. It started snowing later on! The temp gauge didn't get above 52 degrees on the drive home (mainly motorway). Once I hit traffic it increased to 85 after 15 mins of stop start traffic,then the fans kicked in. 75 degrees in traffic doesn't sound right to me, especially if the fans don't kick in.
With mine, and we know they can all be a bit different depending on age, mileage, engine size, mods...
When the car was new(ish) I can remember very well spending 3+ hours negotiating London traffic in temperatures of 33C+ and while I suffered personally a great deal, the engine temp never went over 90/95C, though the fans cut in regularly though not frequently when stationary.
In winter in sub-zero, it could run a bit cool, but generally not below 70C.
So in my experience; the original system in 97/98 was more than up to the job.
Since the radiator change a couple of years back, I find that getting 'hot' is almost impossible, though the fans do cut in much as before, when stationary. Otherwise it runs about 85/90 as 'normal'.
In cooler weather, like we have been having, it will run a bit too cool; maybe as low as 50/60C on the motorway.
It seems overall, that anyone with a cooling system in good condition, and without air, will describe something similar as 'usual'.
It also seems, as spend says, the way to 'fix' it is to use a hotter thermostat in winter.
It's not a new concept, just one that doesn't usually apply in moderate climates like most of Britain.
If you live in the 'real north', having oil changed for a lower viscosity, and a hotter thermostat fitted for winter is common practice.
When the car was new(ish) I can remember very well spending 3+ hours negotiating London traffic in temperatures of 33C+ and while I suffered personally a great deal, the engine temp never went over 90/95C, though the fans cut in regularly though not frequently when stationary.
In winter in sub-zero, it could run a bit cool, but generally not below 70C.
So in my experience; the original system in 97/98 was more than up to the job.
Since the radiator change a couple of years back, I find that getting 'hot' is almost impossible, though the fans do cut in much as before, when stationary. Otherwise it runs about 85/90 as 'normal'.
In cooler weather, like we have been having, it will run a bit too cool; maybe as low as 50/60C on the motorway.
It seems overall, that anyone with a cooling system in good condition, and without air, will describe something similar as 'usual'.
It also seems, as spend says, the way to 'fix' it is to use a hotter thermostat in winter.
It's not a new concept, just one that doesn't usually apply in moderate climates like most of Britain.
If you live in the 'real north', having oil changed for a lower viscosity, and a hotter thermostat fitted for winter is common practice.
I would change the stat. I have had a 74 degree stat all year round for the last 5 years and I always get a warm heater.
The gauge shows a lot less in cold weather but the heater is always the same temp . The gauge just differs as it sits in an air flow that does not necessarily reflect the water temp. If the fans do not come on either when sitting in traffic it would suggest that the stat needs changing or is missing.
The gauge shows a lot less in cold weather but the heater is always the same temp . The gauge just differs as it sits in an air flow that does not necessarily reflect the water temp. If the fans do not come on either when sitting in traffic it would suggest that the stat needs changing or is missing.
Even with a 74 stat thats working okay it should never go below 70 deg or so... as the stat will close again to keep the warm water in the block... and making sure it runs at the correct temps. Running low temps can add all sorts of cr*p to your oil... not a good idea... also the ECU starts to enrich the fuel at about 65 deg!!.. 
TVR Beaver said:
Even with a 74 stat thats working okay it should never go below 70 deg or so... as the stat will close again to keep the warm water in the block... and making sure it runs at the correct temps. Running low temps can add all sorts of cr*p to your oil... not a good idea... also the ECU starts to enrich the fuel at about 65 deg!!..
Hi TVR Beaver just another point of view I have also read reports that it is best to run our old V8s at the lowest temp within it's operating limits to prevent liner damage etc. I believe that my engine runs within this whatever the temp gauge reads. Its only a guide and a bad one at that. No other car I have had and its quite a few, changes the guage reading depending on what the weather is doing.
Its strange that since I have been on this forum (over 5 years ) most post on temperature are trying to keep the temp down with large ally rads etc. . Another typical TVR enigma ??
Prizam said:
I expect you have a dodgey temp sender. There are two of them on the car. A crappy TVR one and an ok rover one.
Swap to the rover sender with the use of a 120 ome resister and your temp gauge will read correctly.
As for luke warm air, you probably need to bleed the heater matrix.
Pretty sure that should be a 170 ohm resistor but if you can verify your engine temp best to get a variable resistor first and trim the gauge exactly. Swap to the rover sender with the use of a 120 ome resister and your temp gauge will read correctly.
As for luke warm air, you probably need to bleed the heater matrix.
A.
WOO5IE said:
Hi TVR Beaver just another point of view
I have also read reports that it is best to run our old V8s at the lowest temp within it's operating limits to prevent liner damage etc. I believe that my engine runs within this whatever the temp gauge reads. Its only a guide and a bad one at that. No other car I have had and its quite a few, changes the guage reading depending on what the weather is doing.
Its strange that since I have been on this forum (over 5 years ) most post on temperature are trying to keep the temp down with large ally rads etc. . Another typical TVR enigma ??
It depends on the gauge type.. analogue or digital... Ours will indeed register every temp movement as it's telling you exact temperature.. and it has no damping like the more modern units...I have also read reports that it is best to run our old V8s at the lowest temp within it's operating limits to prevent liner damage etc. I believe that my engine runs within this whatever the temp gauge reads. Its only a guide and a bad one at that. No other car I have had and its quite a few, changes the guage reading depending on what the weather is doing.
Its strange that since I have been on this forum (over 5 years ) most post on temperature are trying to keep the temp down with large ally rads etc. . Another typical TVR enigma ??
There is an optimum runing temp for petrol engines... I think it's about 78 deg C for best power but needs to go above this to burn off the cr*p that gets into the oil etc... Also the 14 CUX starts to enrich the mixture at 65 and below so you don't want to be driving around on the choke!...
The cylinder issue comes mainly from the RR but on thoese cars they run into the 95c and above....
Yes, I agree you don't want then too hot.. I try keep mine between 82 and 88 deg... but also you don't want to run too cold either
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