Normal engine temperature?
Discussion
keith2.2 said:
I was advised when I bought mine that thes really no such thing as normal, you just have to get a feel for how your car behaves and as long as it doesn't go over 110ish (on a hot track day or sitting in baking sun in traffic..)
110ish! that's too hot surely isn't it?I am finding it hovers between 75 - 85 ish when on move and then fans are in at about 92 - 93.
Granted the comment about accurate gauges.......but if your gauge seems to run between 65 (5am, February, motorway) and 85 (very warm day, driving at 30 in a stream of traffic) then its like mine.
If mine goes above 90 I hear the fans cut in, especially if stuck in traffic, which is when it usually happens, and they stop it going any higher.
If you don't hear the fans, and/or it goes above 90, your fans aren't working properly (or if you do hear them, maybe only one is working). If this happens, up with the bonnet and have a look. No fans, its usually either a dodgy connection in the wiring to the fans (under the rad), or a faulty otter switch. One fan, then most likely dodgy wiring. Waggle the connectors. Not usually fuses IMHO.
Otter switch is a standard Ford part IIRC for the later cars and is low down on the back of the rad, passenger side. Earlier cars its on the bottom of the swirl pot. Short it out to test it - pull the leads half off and stick a screwdriver across the bare terminals. What you are doing is shorting out the switch, ie making it permanently live. If fans start working, it's the otter switch to replace, £10-15. If they don't, get someone to hold the screwdriver while you waggle the connectors in the fan wiring. It is perfectly possible to have both faults - I did.
If mine goes above 90 I hear the fans cut in, especially if stuck in traffic, which is when it usually happens, and they stop it going any higher.
If you don't hear the fans, and/or it goes above 90, your fans aren't working properly (or if you do hear them, maybe only one is working). If this happens, up with the bonnet and have a look. No fans, its usually either a dodgy connection in the wiring to the fans (under the rad), or a faulty otter switch. One fan, then most likely dodgy wiring. Waggle the connectors. Not usually fuses IMHO.
Otter switch is a standard Ford part IIRC for the later cars and is low down on the back of the rad, passenger side. Earlier cars its on the bottom of the swirl pot. Short it out to test it - pull the leads half off and stick a screwdriver across the bare terminals. What you are doing is shorting out the switch, ie making it permanently live. If fans start working, it's the otter switch to replace, £10-15. If they don't, get someone to hold the screwdriver while you waggle the connectors in the fan wiring. It is perfectly possible to have both faults - I did.
QBee said:
Granted the comment about accurate gauges.......but if your gauge seems to run between 65 (5am, February, motorway) and 85 (very warm day, driving at 30 in a stream of traffic) then its like mine.
If mine goes above 90 I hear the fans cut in, especially if stuck in traffic, which is when it usually happens, and they stop it going any higher.
If you don't hear the fans, and/or it goes above 90, your fans aren't working properly (or if you do hear them, maybe only one is working). If this happens, up with the bonnet and have a look. No fans, its usually either a dodgy connection in the wiring to the fans (under the rad), or a faulty otter switch. One fan, then most likely dodgy wiring. Waggle the connectors. Not usually fuses IMHO.
Otter switch is a standard Ford part IIRC for the later cars and is low down on the back of the rad, passenger side. Earlier cars its on the bottom of the swirl pot. Short it out to test it - pull the leads half off and stick a screwdriver across the bare terminals. What you are doing is shorting out the switch, ie making it permanently live. If fans start working, it's the otter switch to replace, £10-15. If they don't, get someone to hold the screwdriver while you waggle the connectors in the fan wiring. It is perfectly possible to have both faults - I did.
I definately have both fans working and I am sure mine doesn't cut in until about 92 ish, is this too high then?If mine goes above 90 I hear the fans cut in, especially if stuck in traffic, which is when it usually happens, and they stop it going any higher.
If you don't hear the fans, and/or it goes above 90, your fans aren't working properly (or if you do hear them, maybe only one is working). If this happens, up with the bonnet and have a look. No fans, its usually either a dodgy connection in the wiring to the fans (under the rad), or a faulty otter switch. One fan, then most likely dodgy wiring. Waggle the connectors. Not usually fuses IMHO.
Otter switch is a standard Ford part IIRC for the later cars and is low down on the back of the rad, passenger side. Earlier cars its on the bottom of the swirl pot. Short it out to test it - pull the leads half off and stick a screwdriver across the bare terminals. What you are doing is shorting out the switch, ie making it permanently live. If fans start working, it's the otter switch to replace, £10-15. If they don't, get someone to hold the screwdriver while you waggle the connectors in the fan wiring. It is perfectly possible to have both faults - I did.
mattgtd said:
I definately have both fans working and I am sure mine doesn't cut in until about 92 ish, is this too high then?
I refer back to the accurate gauge comment earlier..... You can't judge it by the temp gauge as it's not that accurate. They are normally consitantly off however, so once you have 'set your base' you can reliably use it from then.

My gauge reads between 90 in traffic but drops to 70 on a motorway run.
If you want to check the temperature, you can buy an infrared thermometer from places like Maplin quite cheaply. Just point it at the radiator and other parts of the cooling system to get a temperature reading. That should help to identify if you have a problem or not.
If you want to check the temperature, you can buy an infrared thermometer from places like Maplin quite cheaply. Just point it at the radiator and other parts of the cooling system to get a temperature reading. That should help to identify if you have a problem or not.
Quick question whilst we're on the subject. Do both fans kick in at the same time, or does one start at a lower temperature and then the other kick in when it's really hot? I ask because I notice that only one fan was working on my car the other day. I wonder if that's normal, or if one fan isn't working.
Nope zed, thats not normal as standard anyway, give the wires a wiggle.
Imo theres little point in putting a different standard thermostat in them to lower the temp, would probably cause more problems than good during normal road useage as the cooling system is quite efficient when the car is moving.
If you're worried about stationery temps and your system is working how it should, I would be looking for better fans as the 20 year old ones on there could probably be improved on.
Or get yourself some 2 stage adjustable thermostats..
http://www.demon-tweeks.co.uk/motorsport/fan-contr...
Imo theres little point in putting a different standard thermostat in them to lower the temp, would probably cause more problems than good during normal road useage as the cooling system is quite efficient when the car is moving.
If you're worried about stationery temps and your system is working how it should, I would be looking for better fans as the 20 year old ones on there could probably be improved on.
Or get yourself some 2 stage adjustable thermostats..
http://www.demon-tweeks.co.uk/motorsport/fan-contr...
Edited by s p a c e m a n on Tuesday 1st April 05:51
zed4 said:
Quick question whilst we're on the subject. Do both fans kick in at the same time, or does one start at a lower temperature and then the other kick in when it's really hot? I ask because I notice that only one fan was working on my car the other day. I wonder if that's normal, or if one fan isn't working.
As Spaceman said, definitely both should kick in together. The wires he refers to are in the tray under the radiator, lie loose, and have a white connector in the middle. One set of wires for each fan. Lying where they do the connectors get corroded, so get the engine running and up to fan kick in temps, then grab each set in turn and pull the connectors apart and push them back together againJust to add some confirmation about accuracies / inaccuracies;
Mine (from new) always ran consistently 80ish, up to just under 100 maximum in heavy traffic on a hot day, and fans kicked a little over 90.
A new radiator, and one engine rebuild later, and it consistently runs below 70 at cruise, around 70 at moderate speeds, but fans now come on at just above 80 when sitting in traffic, and it never climbs above 90.
Somewhere I have lost 10 degrees
Even though I see temperatures below 70 on the motorway in cooler weather, the heater always has piping hot air available.
So to confirm what others have said, they can vary a bit from car to car when using original equipment sensors and gauges. Consistency is what you look for, and variation is what you must be on the alert for.
Finally, I 100% backup spaceman and QBee, fans should come on together unless a modification has been made, so have the wiring checked. That could easily bite you as the weather warms up; because you absolutely will need both fans in hot weather / heavy traffic.
Mine (from new) always ran consistently 80ish, up to just under 100 maximum in heavy traffic on a hot day, and fans kicked a little over 90.
A new radiator, and one engine rebuild later, and it consistently runs below 70 at cruise, around 70 at moderate speeds, but fans now come on at just above 80 when sitting in traffic, and it never climbs above 90.
Somewhere I have lost 10 degrees

Even though I see temperatures below 70 on the motorway in cooler weather, the heater always has piping hot air available.
So to confirm what others have said, they can vary a bit from car to car when using original equipment sensors and gauges. Consistency is what you look for, and variation is what you must be on the alert for.
Finally, I 100% backup spaceman and QBee, fans should come on together unless a modification has been made, so have the wiring checked. That could easily bite you as the weather warms up; because you absolutely will need both fans in hot weather / heavy traffic.
For best running and to burn off any nasty stuff getting in the oil, I was told my Mark Adams the optimum temp is around 80 deg... I have a 82 stat fitted that holds it at 78 ish on the motorway... and I see temps of 85 ish around town.. get in traffic and it goes to 91 when the fans kick in...
what I see on my gauge ties up with the stats and sensors fitted so I guess mine is about right....
you don't want to run cold or you will build up nasty stuff in your oil
what I see on my gauge ties up with the stats and sensors fitted so I guess mine is about right....
you don't want to run cold or you will build up nasty stuff in your oil

Gassing Station | Chimaera | Top of Page | What's New | My Stuff


