Temperature gauge has always, after a few minutes sat in the middle of hot/cold (no numbers) previously.
Recently, after a couple of mins setting off, it rises to the middle as expected, but after about 6 miles/10 mins it shoots right up to HOT (no lights or anything come on) then settles back down after a couple mins/miles.
It seems to only do this on the first journey of each day (ie after an overnight park). It can sit at work for 8 hours and it's fine on the journey home.
Anyone know the likely culprit given the above - Coolant Temp Sensor? Thermostat?
TIA
|
I'd suspect the thermostat. It would seem to be sticking in the closed position until it gets really hot and then opens.
When was it last/has it ever been changed?
Good excuse to give the system a flush, it's probably due on a car that age.
Weather's looking warmer for the weekend!
|
|
Thanks, sounds like a reasonable assumption. Around £15 on ebay.
|
Don't panic, but keep an eye on the temperature gauge.
I've just dragged up from my memory a tale of a Maxi that displayed the same symptoms. The owner thought it would go away, until one day the thermostat didn't open. You can guess the rest!
|
If it's anything like the gauges on the MX5 of the same era, and it sounds as if it is, the, it's not really a gauge at all. Hence no numbers. If it's in the normal range, it just points to the middle. Too hot, and it goes to H. So it's possible that it's running hot all the time at the cusp of the normal range rather than actually having a big temperature increase.
But I agree a sticking or defective thermostat could still explain it.
I hate those fraudulent gauges. The MX5 oil pressure 'gauge' is the same, pointing at exactly the same spot at tickover or 6000rpm.
|
|
Whether you put numbers on the gauge,blue-white-red or C-N-H,the internals are the same.As with an oil pressure gauge,it may well show the same pressure at all times-it shows that the pressure relief valve is working.
|
It's now not doing it.
Not sure if I should just replace the thermostat or not? It's only £15, but if I go down that road, there are a hundred other things I could also replace!
|
>>It's now not doing it.
It's luring you into a false sense of security, they're psychic you know!
;>)
|
>> It's luring you into a false sense of security
Quite!
Same symptoms this morning again.
Thermostat ordered from ebay - eight quid
|
>> Whether you put numbers on the gauge,blue-white-red or C-N-H,the internals are the same.As with an
>> oil pressure gauge,it may well show the same pressure at all times-it shows that the
>> pressure relief valve is working.
It's likely that gauge end is basically similar whether it is a calibrated or an on/off arrangement.
I have been trying to find a source, and haven't yet, but I did stumble on this description of how to get a proportionate reading from the MX5 oil pressure gauge.
www.miata.net/garage/opg2/
As you will read, the sender is basically designed to operate a light, so the standard gauge set up gives you no information other than good/bad.
I'm pretty sure some temperature gauges operate on non-calibrated lines too, having observed a good number over the years. I'm absolutely certain that my oil pressure gauge comes into that category, as it shows the same pressure at 800rpm and 7000rpm. I have never seen a proper gauge do that.
The usual cause of gauge problems is a bad earth.
Last edited by: Manatee on Wed 24 Apr 13 at 14:36
|
|
It could be the sign of a poor engine>body earth connection.
|
|
That sound easy enough to check/clean up for free when I'm having a poke around for the oil leak.
|
Narrowed down the oil leak to the distributor. A common problem. www.club323f.com/?page_id=1137.
But maybe not that common, A quick google for the 'O' ring throws up results from international ebay sellers at over £30!
At least with the distributor off, access to the thermostat will be easier :)
|
Managed to find the O Ring for 99p (ford probe store if anyone is looking in future), so i'll fit that and the thermostat (£9) this weekend.
But a few other issues i'll take to the other thread in the discussion forum.
|
Quick update - It was indeed the thermostat. New one fitted and for the last few weeks the temperature dial rises to the middle and stays there.
I now have a very small coolant leak from the thermostat housing though. ---sigh---
Access was bad enough when I had the distributor off!
|
>> I now have a very small coolant leak from the thermostat housing though. ---sigh---
>>
Finally got around to sorting this. Removed the housing and found a little bit of the old gasket still stuck below the new one - doh. Oh well, you live and learn.
At least the thermostat came with 3 gaskets - a bit of trimming and all is right.
|
Mazda 323 - 97 1.8 Temp Sensor / Thermostat? - bathtub tom
