Overheating or is it?
Discussion
I've recently bought a Triumph Spitfire (Nostalgia trumped logic) with a few faults that I'm working my way through. At the moment i'm trying to get to the bottom of the temperature running hot.
1. On the gauge the temp climbs until just below the red.
2. Removing the thermostat has made no difference.
3. The radiator is warm at the top and cool at the bottom.
4. The thermostat housing is the hottest component (80 degrees C)
5. Top hose is cooler at about 60 degrees C.
6. Engine block is about 40 degrees C.
Does that give any one any thoughts about where the problem might be?
1. On the gauge the temp climbs until just below the red.
2. Removing the thermostat has made no difference.
3. The radiator is warm at the top and cool at the bottom.
4. The thermostat housing is the hottest component (80 degrees C)
5. Top hose is cooler at about 60 degrees C.
6. Engine block is about 40 degrees C.
Does that give any one any thoughts about where the problem might be?
Not sure that I can help too much, but the rad should be hot all over. Sounds like there is no circulation,possibly due to an air lock,or some other reason. I guess it's possible the water pump is not circulating. My thoughts for what they are worth.
Defo nostalgia over logic - but then, nostalgia isn't what it used to be......
Defo nostalgia over logic - but then, nostalgia isn't what it used to be......
80 degrees C isn't normally anything to worry about so you are probably looking at a gauge reading incorrectly and as most don't actually have temperatures on them (just a red area) it is impossible to tell this.
You say the bottom is cool, how cool?
Yes, as above it is indeed possible you may have an air lock, running it up to temperature with the cap off the rad & the heater on full will quite often clear this. It is also possible you have a stat which doesn't have a bleed hole on it, some cars don't like these as they can help an airlock to form in the stat area.
When bleeding some cars you need to jack the front of the car up as high as you can to help air locks out.
It is also possible you have a dodgy water pump as above as the temperature of all elements of the cooling system should be pretty similar when any air locks have been removed.
You say the bottom is cool, how cool?
Yes, as above it is indeed possible you may have an air lock, running it up to temperature with the cap off the rad & the heater on full will quite often clear this. It is also possible you have a stat which doesn't have a bleed hole on it, some cars don't like these as they can help an airlock to form in the stat area.
When bleeding some cars you need to jack the front of the car up as high as you can to help air locks out.
It is also possible you have a dodgy water pump as above as the temperature of all elements of the cooling system should be pretty similar when any air locks have been removed.
the pips said:
1. On the gauge the temp climbs until just below the red.
All that's doing is comparing the resistance of the sender with the gauge's needle. If the sender and gauge are mismatched, or the wiring between the two is iffy, then you're going to get meaningless "absolute" readings. Their value lies in where the needle is compared to its "normal".the pips said:
4. The thermostat housing is the hottest component (80 degrees C)
Which is as it should be.the pips said:
5. Top hose is cooler at about 60 degrees C.
Going to the rad?the pips said:
6. Engine block is about 40 degrees C.
Measured where and how?The rad should be hot all over. You've come up with some numbers - do you have an IR thermometer?
Put the 'stat back in - that's not sounding like it's your problem, and running without it is probably confusing more than it's clearing.
If you think it might be iffy, then just put a new one in. They're cheap. If you're getting to 80deg, THEN the top of the rad starts to get warm, it's working.
With the stat refitted & system filled start & allow to warm up. Keep checking the top hose. It should suddenly get hot as the stat opens. If it warms up gradually & inline with the rest of the engine then the stat is either faulty or missing.
What has the vendor said about the gauges usual position?
Is the coolant temp sensor faulty? I've had a couple go on the RRC & the gauge can do odd things.
Have you replaced the stat with a good quality new one?
This may be of interest:
https://www.canleyclassics.com/technical-archive/o...
What has the vendor said about the gauges usual position?
Is the coolant temp sensor faulty? I've had a couple go on the RRC & the gauge can do odd things.
Have you replaced the stat with a good quality new one?
This may be of interest:
https://www.canleyclassics.com/technical-archive/o...
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