My 2000 Miata is starting to overheat @ 85,000 miles. Is it a week fan motor
or just needs a good cooling system flush?
pws - 18 Sep 2006 03:55 GMT
> My 2000 Miata is starting to overheat @ 85,000 miles. Is it a week fan motor
> or just needs a good cooling system flush?
Has it ever had a flush? If not, then it needs it anyway, but it may not
be the problem. Overheating can be from a number of reasons. I would
check the coolant level first.
If it is normal, I would suspect the thermostat, which is another item
that should be replaced by 85K miles.
If it is low, I would replace the thermostat, radiator cap, and make
sure the coolant reservoir overflow system is properly hooked up.
That would be after making certain that there wasn't another obvious
leak somewhere else like a pinhole leak in a coolant hose or the
radiator itself.
If it is leaking internally, it is time to look at the oil for coolant
and the coolant for oil, but that is your worst-case scenario.
It could be the fan, it would be unusual at this age and mileage, but
not impossible.
Is the heating intermittent? Does it go all the way to the red? Does it
overheat only at low speeds or at highway speeds as well? Do you have
A/C and does this affect the gauge? Finally, are you certain that it is
not the temperature gauge or sending unit itself?
Someone here can probably point you in the right direction with a few
more details.
Pat
Jungwoo Ha - 18 Sep 2006 05:13 GMT
> My 2000 Miata is starting to overheat @ 85,000 miles. Is it a week fan motor
> or just needs a good cooling system flush?
Maybe your thermostat or water pump gone wrong.
It is recommended to replace it when you do the timing belt change.
Check this article.
http://www.miata.net/garage/water_pump.html
-j
Michael Frohlich - 18 Sep 2006 18:18 GMT
The coolant level hasn't dropped. The temp goes midway between the half way
mark to the off the scale mark and only above 80 mph especially with the a/c
on. It will stay cool all day if you just putt around.
> My 2000 Miata is starting to overheat @ 85,000 miles. Is it a week fan
> motor or just needs a good cooling system flush?
pws - 18 Sep 2006 21:49 GMT
> The coolant level hasn't dropped. The temp goes midway between the half way
> mark to the off the scale mark and only above 80 mph especially with the a/c
> on. It will stay cool all day if you just putt around.
Your fan is working if the car is staying cool at low speeds. At highway
speeds, the faster movement of air through the radiator should be
providing adequate airflow to keep the car cool.
Have you checked for any obstructions on the grill and radiator area?
The fans provide air from the back, so the symptoms would make sense if
something is partially blocking the front airflow through the radiator.
I would still replace the thermostat, it may be going out but is still
partially working, and replacing it is cheap and easy. A full coolant
flush as well if it has been 2 or more years.
Pat
Michael Frohlich - 19 Sep 2006 00:53 GMT
Yea, I'm going to start with the cheap stuff. Thanks for the advice.
>> The coolant level hasn't dropped. The temp goes midway between the half
>> way mark to the off the scale mark and only above 80 mph especially with
[quoted text clipped - 13 lines]
>
> Pat
Iva - 19 Sep 2006 01:48 GMT
> Yea, I'm going to start with the cheap stuff. Thanks for the advice.
It's always best to start with the cheap stuff. A new thermostat and a new
radiator cap took care of my 1990's intermittent overheating problem. And
that was a whole lot less expensive than a new radiator!
Iva & Belle.)
'90B Classic Red.)
#3 winkin' Miata
Frank Berger - 19 Sep 2006 06:09 GMT
> My 2000 Miata is starting to overheat @ 85,000 miles. Is it a week fan
> motor or just needs a good cooling system flush?
95K on my '96. No problems with thermostat, fan motor, nor radiator cap.
Had to replace the radiator, though. So any of the former may be more
likely, but don't be surprised if it's the latter.
Chuck - 19 Sep 2006 22:28 GMT
While I might replace a radiator that has plastic tanks--(because every one
I've had has failed with a split in the plastic)
A simple removal and good flush should have cured the problem with the
radiator.
If the radiator was previously repaired, the shop may have used the wrong
black paint, and screwed up the heat transfer.
> > My 2000 Miata is starting to overheat @ 85,000 miles. Is it a week fan
> > motor or just needs a good cooling system flush?
> >
> 95K on my '96. No problems with thermostat, fan motor, nor radiator cap.
> Had to replace the radiator, though. So any of the former may be more
> likely, but don't be surprised if it's the latter.
Frank Berger - 19 Sep 2006 23:13 GMT
To posting beacause you did:
How is a a good flush going to cure a leaking radiator?
> While I might replace a radiator that has plastic tanks--(because every
> one
[quoted text clipped - 10 lines]
>> Had to replace the radiator, though. So any of the former may be more
>> likely, but don't be surprised if it's the latter.
Chuck - 20 Sep 2006 22:42 GMT
The original poster has a cooling problem, not a leak.
"The coolant level hasn't dropped. The temp goes midway between the half way
mark to the off the scale mark and only above 80 mph especially with the a/c
on. It will stay cool all day if you just putt around."
> To posting beacause you did:
>
[quoted text clipped - 14 lines]
> >> Had to replace the radiator, though. So any of the former may be more
> >> likely, but don't be surprised if it's the latter.
Michael Frohlich - 23 Sep 2006 22:37 GMT
Thanks chuck for clarification.
> The original poster has a cooling problem, not a leak.
>
[quoted text clipped - 26 lines]
>> >> more
>> >> likely, but don't be surprised if it's the latter.