Sounds very likely to be a knackered thermostat or water pump; it's not unknown for the water pump impellers to break causing these symptoms. If it is the pump then you might as well get a new timing belt and tensioners fitted unless it's very recently been done, since you have to remove the belt to change the pump anyway.
Oil temp rising when stationary
- Thread starter phil675
- Start date
Soldato
What about the fan? I havent seen a comment from the OP that would rule it out?
If its ECU controlled then it will be seeing the same temp as the ECU and that should be same as the dash. Sometimes they could all have seperate sensors with the fan switch in the rad end tank such that the ECU and dash sensor on the head/block will see different temps to the fan switch.
If its ECU controlled then it will be seeing the same temp as the ECU and that should be same as the dash. Sometimes they could all have seperate sensors with the fan switch in the rad end tank such that the ECU and dash sensor on the head/block will see different temps to the fan switch.
I think fan too. I wouldn't run it until I was sure the fan worked personally but it doesn't sound like that is going to happen. So when you get to work if the gauge says it's hotter than it should be get out before you stop the engine, pop the bonnet and have a look to see if the fan is running.
Engine over heating when stationary but cooling back down when moving screams fan or fan switch to me.
Engine over heating when stationary but cooling back down when moving screams fan or fan switch to me.
It's a possibility, but it takes quite a long time for the fan to kick in when it's freezing outside, and even then you wouldn't see such a sudden rise in temperature if the rest of the cooling system was working, it would be more gradual. The symptoms of rapid temperature rise points to lack of coolant flow IME.
Man of Honour
I had a similar thing happen to my 45 around this time last year. Engine fine when moving, but the coolant temp rose quickly when stationary. It was enough for the fan to noisily kick in. There were other symptoms too, however, the car was using a small amount of coolant and it would sometimes struggle to start. Turned out to be the early stages of HGF.
Coolant temp will always rise when stationary.
This is normal.
Even in the cold.
Is yours getting hot, or overheating?
And the 30ish sounds about right, itsactually really about 20mph or above before radiator passive cooling has good enough effect to start to lower the temp. A mile or so, high gear low revs, sorted.
This is normal.
Even in the cold.
Is yours getting hot, or overheating?
And the 30ish sounds about right, itsactually really about 20mph or above before radiator passive cooling has good enough effect to start to lower the temp. A mile or so, high gear low revs, sorted.
Soldato
It should never go above halfway on the temperature gauge of a ZS, if it does then something is wrong.
I'd change the thermostat and also make sure the radiator fan is working.
Do the heaters work properly?
Heaters working all the time normally points to stuck thermostat or broken rad fan.
Heaters not working or weak normally indicates either an air lock, or a faulty water pump.
I'd be inclined to ignore any garage / person that jumps up and shouts OMG HGF! as in my experience, it really isn't as prominent as you'd think.
I've owned 3 K series engined cars, covered over 100,000 miles in that time, and only had one start to show signs, but my fault for properly overheating it due to a leaking water pump.
The other 2 were fine, and they get a heavy right foot day in, day out.
I'd change the thermostat and also make sure the radiator fan is working.
Do the heaters work properly?
Heaters working all the time normally points to stuck thermostat or broken rad fan.
Heaters not working or weak normally indicates either an air lock, or a faulty water pump.
I'd be inclined to ignore any garage / person that jumps up and shouts OMG HGF! as in my experience, it really isn't as prominent as you'd think.
I've owned 3 K series engined cars, covered over 100,000 miles in that time, and only had one start to show signs, but my fault for properly overheating it due to a leaking water pump.
The other 2 were fine, and they get a heavy right foot day in, day out.
Soldato
Not on the dash it shouldn't
Most cars now sit at middle between 85-100 C with the typical thermostat an 88C item.
Took it to a reputable garage, they said the water pump is leaking (engine bay did smell a bit like antifreeze but the tank level hadn't moved much) and they did a block test and found the head gasket to be wrong (in more words).
So I'm having a new belt, water pump and head gasket with the head skimmed, oil and coolant for £700. Quite a ballache.
Edit: Also the problem seemed to be worse. From a cold start it took about 10 seconds for the temp gauge to hit the middle, which seems impossible to get that hot so quickly, rose to 3/4 just slowing down for roundabouts. Fan was going full pelt.
So I'm having a new belt, water pump and head gasket with the head skimmed, oil and coolant for £700. Quite a ballache.
Edit: Also the problem seemed to be worse. From a cold start it took about 10 seconds for the temp gauge to hit the middle, which seems impossible to get that hot so quickly, rose to 3/4 just slowing down for roundabouts. Fan was going full pelt.
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Unfortunately the leaking water pump is quite possibly what caused the head gasket to go. The K series holds a very small amount of coolant in order to improve warm up times, but this means that only a small leak can seriously degrade the cooling system. This is why you need to regularly check the coolant level - if you notice a leak soon after it starts you can avoid any further damage.
£700 seems a bit steep to me, there are certainly MG specialists that would do it for less. Changing the timing belt when you have to remove the head anyway is virtually a free job in terms of labour.
I would insist that the inlet manifold gasket is changed at the same time, it will take them minutes and the gaskets are cheap (a few pounds) but are a known weak point for coolant leaks.
So the cooling system heats up and cools down, but without the CTS reporting the change to the temp guage?
Soldato
The temp gauge won't move, as it's designed to sit at the same point for (usually) between 80 and 110 degrees, as mentioned previously.
Also, I reckon they've had you on the HG, none of the symptoms point to that.
Also, I reckon they've had you on the HG, none of the symptoms point to that.
Soldato
Not just on MG Rovers, otherwise you'd get people panicking that it was moving up or down. 
Quite standard, and I see the reasoning. Although it is annoying when you do have a problem, by the time you notice, your head is banana shaped.
Quite standard, and I see the reasoning. Although it is annoying when you do have a problem, by the time you notice, your head is banana shaped.
Soldato
I'd question whether the head gasket has anything wrong with it mate. Get a leak down test and a compression test done at a different garage to verify what the other is claiming.
Soldato
Sounds totally crap to me!
Considering the fan somes on around 95-100 in most cars you would only want the temp gauge showing an event outside the 'normal' cooling system parameters.
Then when it does rise above normal you know something must be up and investigate!
Man of Honour
I only heard the fan come on in mine once in the entire 2 years I owned it, and that was when it was stationary for a couple of minutes in the freezing cold a couple of weeks before the HG failed. It was loud and noticeable enough for me to think 'what the heck is that' (or similar). Before that time the temp gauge never ever moved above halfway even in mid summer, at that point it was heading towards 3/4 - obvious something was up!
I don't think they'd bother, I saw they're book and they are completely full, hopefully they can get it done by the end of next week. I don't want to move the car as I might cause more damage and it has definitely been getting hot faster over the last few days.