Chimaera overcooling.
Discussion
I'm no expert but afaik the otter switch turns the fans on at a set temp(88 C ??) so a change wouldn't affect anything because if they come on the engine must be up to temp. However changing the stat might but is it worth it .Maybe stick to the blanking idea
>> Edited by ray_von on Wednesday 28th December 10:46
>> Edited by ray_von on Wednesday 28th December 10:46
cant think of much to be honest mate.
Otter switch only relevant if its getting to the temp in the first place.
Thermostat too much of an arse to change every 3 months...
reckon the cardboard idea is the easy way forward. Use black cardboard and you probably wouldnt notice. or sketch "sparco" or something on it
Otter switch only relevant if its getting to the temp in the first place.
Thermostat too much of an arse to change every 3 months...
reckon the cardboard idea is the easy way forward. Use black cardboard and you probably wouldnt notice. or sketch "sparco" or something on it
It was particularly parky on that run across Dartmoor yesterday Corin, my 4.0L struggled to get above 60 on the guage!
I seemed to use more fuel too, but I guess that could be related ???
Starting to wonder if my thermostat is stuck open - air from the heater was none too toasty either (Mary was freezing in the passenger seat).
Simon
I seemed to use more fuel too, but I guess that could be related ???
Starting to wonder if my thermostat is stuck open - air from the heater was none too toasty either (Mary was freezing in the passenger seat).
Simon
I'm new to TVR ownership + Pistonheads - but need to start joining in somewhere.
So - if there is such a thing as comfort in numbers ....
Mine too struggles to get above 60 on open roads in this colder weather. Soon warms up in town or slower driving.
In days of driving Hillman Imp (many years ago) would have been bl**dy delighted!
So - if there is such a thing as comfort in numbers ....
Mine too struggles to get above 60 on open roads in this colder weather. Soon warms up in town or slower driving.
In days of driving Hillman Imp (many years ago) would have been bl**dy delighted!
There are very few problems that can cause over-cooling. Running cold almost always indicates that the stat is missing or faulty. Occasionally it is caused by the gauge misreading. If somebody has helpfully 'cured' an overheating problem by tweaking the gauge, then it will read low in the winter.
If your car is running cool when driving but then rising to normal temp in traffic or when stationary it would suggest that there is not a problem with the system itself, it may just be that the exeptional cold air flowing through the engine bay on its own is enough to keep the temp in the 60 to 70 degree range, and the thermostat is staying shut.
When I drove mine in the cold, I noticed a definate raise in temp after the air splitter had fallen off.
When I drove mine in the cold, I noticed a definate raise in temp after the air splitter had fallen off.
There was an earlier thread on this but couldnt find so...
IIRC the temp sender that makes the dash guage work is affected by the cold airflow throught the engine due to its position. So it misreports the temp of the engine. I can confirm this is the case with my '97 450 which shows about 55 this time of year, yet the heater puts out lovely toasty hot air and the fans kick in if Ive been giving it some stick then sit in a Q for a bit. Temp guage jups up if I sit still for a bit then immediately drops when I start moving again. And I mean a big drop not the normal drop you get when getting air over the rad. In summer the guage works ok and matches the fans kicking in and out. DOnt forget the temp guage sender is not related to the fan otter switch.
So I suspect they all do this - but it doesnt mean you dont have a fault. If your heater is running cold or cool then I would suggest you have a real problem as mines nice and warm.
Maybe the stat is out of order. Quickest way to tell that I have heard is to start with a stone cold engine, pop the top off the swirl pot and start her up. You shouldnt see more than the smallest of motion in the pot and this will usually be caused by the small bleed through holes in the stat. If you get lots of action in the pot then the stat is knackered.
All of the above from memory, I am surely no expert !
Dodsy
IIRC the temp sender that makes the dash guage work is affected by the cold airflow throught the engine due to its position. So it misreports the temp of the engine. I can confirm this is the case with my '97 450 which shows about 55 this time of year, yet the heater puts out lovely toasty hot air and the fans kick in if Ive been giving it some stick then sit in a Q for a bit. Temp guage jups up if I sit still for a bit then immediately drops when I start moving again. And I mean a big drop not the normal drop you get when getting air over the rad. In summer the guage works ok and matches the fans kicking in and out. DOnt forget the temp guage sender is not related to the fan otter switch.
So I suspect they all do this - but it doesnt mean you dont have a fault. If your heater is running cold or cool then I would suggest you have a real problem as mines nice and warm.
Maybe the stat is out of order. Quickest way to tell that I have heard is to start with a stone cold engine, pop the top off the swirl pot and start her up. You shouldnt see more than the smallest of motion in the pot and this will usually be caused by the small bleed through holes in the stat. If you get lots of action in the pot then the stat is knackered.
All of the above from memory, I am surely no expert !
Dodsy
Mine is the same. Concerned, I started from cold and let it get up to temperature while stationary. Hose to radiator eventually started to get hot as the thermostat opened, then after a while longer the fans kicked in at an indicated approx 88, so all appears ok. Went for a run and the temperature dropped down to below 60. Was initially concerned, but now put it down to the sensor location and a good cooling system! Works fine in the summer, and on track days! Oil pressure shows typical characteristic of initially 45 ish, dropping to 30 when warm. Heater works fine.
Bomber Denton said:
This time of year I find it hard on a run to keep the car at optimum running temp, last year on a long run I blanked off half the radiator, is there any other way of doing it bar changing the otter each season?
Corin,
Is the temp normal when stuck in traffic ? If so then the problem is probably that the thermostat is stuck open. I could also be tested by going for a run and then sitting in a car park with the engine running until the fans come on. If the fans come on at the normal 92 deg then its the thermostat that has probably stuck open. If not then there is a different problem.
I had a problem with cool running, temp gauge only went over 70deg when i hit traffic and when i went to change the thermostat it was missing.
Anyway i put one in (30 min job) and on tuesday i drove from newcastle (left at 8pm) to worthing (arrived 1:30am) in the snow so it was very cold and the temp gauge showed 80deg all the way down.
Just take the lid of the swirl tank, start the car and see what the water flow is like. If there is a trickle your stat is probably ok, if it is flowing fast when cold replace your stat.
Anyway i put one in (30 min job) and on tuesday i drove from newcastle (left at 8pm) to worthing (arrived 1:30am) in the snow so it was very cold and the temp gauge showed 80deg all the way down.
Just take the lid of the swirl tank, start the car and see what the water flow is like. If there is a trickle your stat is probably ok, if it is flowing fast when cold replace your stat.
Thanks everyone! 
The gauge indicates near normal readings when stuck in traffic (slightly lower than summer as to be expected) and the heater still blows out toasty air when on a run so i am putting it down to the system being O.K. but just out of curiousity I'm going to change the stat anyway then I know it's done.
The gauge indicates near normal readings when stuck in traffic (slightly lower than summer as to be expected) and the heater still blows out toasty air when on a run so i am putting it down to the system being O.K. but just out of curiousity I'm going to change the stat anyway then I know it's done.
Today in -7C to -2C mine fluctuacted between 80 and 95 depending on traffic - once it had actually got warm. About the same as I get in summer.
[edit]Oh - it did reduce to about 75 ish when I had the heater on full blast. With the fan on 1 it ran normal temperature. Could the additional cooling be due to enthusiastic use of the heater ? [/edit]
>> Edited by Bob the Planner on Friday 30th December 10:41
[edit]Oh - it did reduce to about 75 ish when I had the heater on full blast. With the fan on 1 it ran normal temperature. Could the additional cooling be due to enthusiastic use of the heater ? [/edit]
>> Edited by Bob the Planner on Friday 30th December 10:41
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