Running temperature too high???
- Thread starter rockdemon
- Start date
Does make me wonder whether you guys who have these sorts of problems should be investigating electric water pumps? Currently when you are stuck in traffic the fluid stops moving around the engine and the fan slows down... An electric water pump would at least work at the right speed no matter what???
rp61973 wrote,...
Hello rp,
I would imagine that the only time you would ever be in a position to feel a possible difference would be either while accelerating "flat stick" or at high speed, and in the latter instance the fan is essentially reduntant. Did you record a fuel consumption reduction with the engine fan not running?
If you have an 85 degree thermostat (I think it is likely an 82), then the stat will begine to open at 85 degrees C and be fully open at 95 degrees C. There is always a 10 degree window from first cracking open to being fully open to allow maximum coolant flow.
Ron.
Hello rp,
I would imagine that the only time you would ever be in a position to feel a possible difference would be either while accelerating "flat stick" or at high speed, and in the latter instance the fan is essentially reduntant. Did you record a fuel consumption reduction with the engine fan not running?
If you have an 85 degree thermostat (I think it is likely an 82), then the stat will begine to open at 85 degrees C and be fully open at 95 degrees C. There is always a 10 degree window from first cracking open to being fully open to allow maximum coolant flow.
Ron.
Hi Sydney,
No I haven't recorded the MPG. I think you are right - this is an 85 deg C thermostat, not an 82.
I accept what you say about the stat opening window, but it is the remarkable speed at which the temp rises from being just in the green on the gauge to a temperature where the Kenlowe kicks in (around 85+ degrees). We are talking about 2-3 mins. With an uprated rad surely this can't be right?
When this happens, the Kenlowe switches on, runs a few mins, goes off. 20 seconds later switches on, runs and few mins...etc...
No I haven't recorded the MPG. I think you are right - this is an 85 deg C thermostat, not an 82.
I accept what you say about the stat opening window, but it is the remarkable speed at which the temp rises from being just in the green on the gauge to a temperature where the Kenlowe kicks in (around 85+ degrees). We are talking about 2-3 mins. With an uprated rad surely this can't be right?
When this happens, the Kenlowe switches on, runs a few mins, goes off. 20 seconds later switches on, runs and few mins...etc...
Couldnt that be because the stat temp is that little bit too high? If you swapped the 85 for an 82 or 79 wouldnt the flow through the rad would be steadier (can someone else confirm?)
As it is, your stat opens, kenlowe cools it, stat closes, engine heats stat opens again etc???
Rich.
As it is, your stat opens, kenlowe cools it, stat closes, engine heats stat opens again etc???
Rich.
rp61973 wrote,...
Hello RP,
If I am understanding correctly,..this only happens,...the rapid rise in temperature when stationary in traffic on a warmish day, when the engine driven fan is not running,..only the Kenlow.
If you run the engine driven fan and disconnect the Kenlow,..what happens? The same rapid rise in temperature or something different?
When you take the fan belt off, by what means do you run the water pump?
Ron.
Hello RP,
If I am understanding correctly,..this only happens,...the rapid rise in temperature when stationary in traffic on a warmish day, when the engine driven fan is not running,..only the Kenlow.
If you run the engine driven fan and disconnect the Kenlow,..what happens? The same rapid rise in temperature or something different?
When you take the fan belt off, by what means do you run the water pump?
Ron.
Two questions, first off how big is the Kenlowe? Second, what happens to the temperature guage once the Kenlowe cuts in?
When stationary at idle, especially after being under power (so that there is an overshoot of heat waiting to come out of the engine), I don't have too much of a problem with a rapid rise in temperature. The upgraded rad is irrelevant in these circumstances because there is no air flow through the rad. But there ought to be a fairly rapid return to normal once the Kenlowe starts.
Once the car is moving, normal airflow should be sufficient above, say, 15mph without use of the Kenlowe.
There are peripheral issues, such as how is the fan fixed? It should be tight to the rad and there should be the minimum possibility of air, having passed through the rad once, being able to find its way back for a second run. Is there a pilot hole in the thermostat? What engine speed is your idle set at - very high or very low?
Chris
When stationary at idle, especially after being under power (so that there is an overshoot of heat waiting to come out of the engine), I don't have too much of a problem with a rapid rise in temperature. The upgraded rad is irrelevant in these circumstances because there is no air flow through the rad. But there ought to be a fairly rapid return to normal once the Kenlowe starts.
Once the car is moving, normal airflow should be sufficient above, say, 15mph without use of the Kenlowe.
There are peripheral issues, such as how is the fan fixed? It should be tight to the rad and there should be the minimum possibility of air, having passed through the rad once, being able to find its way back for a second run. Is there a pilot hole in the thermostat? What engine speed is your idle set at - very high or very low?
Chris
Hi,
The rapid rise in heat happens on a warmish day (20 deg + day) after a run. I removed the fan blades only, not the belt (as the alternator relies on the same belt).
If I disconnect the Kenlowe and run the car stationary with the crank driven fan on a warmish day, the temperature will still rise through the gauge but much slower until it nudges the red. To be honest I haven't taken it past this point for fear of overheating.
The Kenlowe is the one supplied by them for the 3500V8 model of P6. It pulls the air through the grille and is mounted on the front of the rad with ties that pass through the fins. The Kenlowe does get the temp down pretty quickly but it tends to rise and then it eventually gets to the point when it is cutting in and out too frequently (only with the crank fan removed). If I replace the crank fan the Kenlowe only cuts in when I have been sitting in traffic for a reasonable time.
Idle speed is around 700 rpm. I don't believe there is a pilot hole in the stat - 3 years or so since I changed it last - I can check - does it make much difference?
Rgs
The rapid rise in heat happens on a warmish day (20 deg + day) after a run. I removed the fan blades only, not the belt (as the alternator relies on the same belt).
If I disconnect the Kenlowe and run the car stationary with the crank driven fan on a warmish day, the temperature will still rise through the gauge but much slower until it nudges the red. To be honest I haven't taken it past this point for fear of overheating.
The Kenlowe is the one supplied by them for the 3500V8 model of P6. It pulls the air through the grille and is mounted on the front of the rad with ties that pass through the fins. The Kenlowe does get the temp down pretty quickly but it tends to rise and then it eventually gets to the point when it is cutting in and out too frequently (only with the crank fan removed). If I replace the crank fan the Kenlowe only cuts in when I have been sitting in traffic for a reasonable time.
Idle speed is around 700 rpm. I don't believe there is a pilot hole in the stat - 3 years or so since I changed it last - I can check - does it make much difference?
Rgs
The Kenlowe cutting in and out when stationary is exactly how it is supposed to work! I doubt very much it will cut in much when you are running at speed.
I think you need to get the thermostat back to standard - ie an 82C one with a pilot hole/jiggler. There are some on Ebay at the moment:
http://cgi.ebay.co.uk/ROVER-ASTON-J...arts_Vehicles_CarParts_SM&hash=item19bf4de079
Then you can play with the Kenlowe adjustment stat so that the Kenlowe cuts in around mid point of the green.
It really doesn't sound to me like there is a great deal wrong.
Chris
I think you need to get the thermostat back to standard - ie an 82C one with a pilot hole/jiggler. There are some on Ebay at the moment:
http://cgi.ebay.co.uk/ROVER-ASTON-J...arts_Vehicles_CarParts_SM&hash=item19bf4de079
Then you can play with the Kenlowe adjustment stat so that the Kenlowe cuts in around mid point of the green.
It really doesn't sound to me like there is a great deal wrong.
Chris
Just a little update on my issues with the apparent high running temperature. Changing the temp sender now has the needle generally pointing at the 5 of the 85 on the gauge. There is also a rubbish piece of wiring from the sender with aplastic connector, so i'm going to have that apart and solder it and hopefully we'll be all the way there 
Thanks for all the great advice as always,
Rich.
Thanks for all the great advice as always,
Rich.
ghce
Well-Known Member
Cannot remember if it was mentioned before (and too lazy to read back in the thread) but also the instrument regulator may be slightly off however reading on the 5 instead of the 8 or in the middle of the 8and 5 certainly sounds alot better, it may well be that the variation in gauge manufacture is the determining factor. I do not know what the instrument regulator voltage is meant to be (with out consulting the workshop manual someone chime in) but aftermarket ones are available.
graeme
graeme
Hi Chris,
I changed the thermostat today for the jiggle pin model which Classeparts kindly dispatched to me. Many thanks - I am now getting a steady temp reading once the thermostat opens (just below the '8' on the gauge). After running the car for around 1/4 hour after the stat opening all seems good.
I changed the thermostat today for the jiggle pin model which Classeparts kindly dispatched to me. Many thanks - I am now getting a steady temp reading once the thermostat opens (just below the '8' on the gauge). After running the car for around 1/4 hour after the stat opening all seems good.