Running too cold???
#1
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Running too cold???
I know its like winter out there, but my car never seems to warm up.. no matter how long or hard I drive.
Its about 6 degrees C outside and I just drove home before, about 20 minute drive, I'd run the car only 1.5 hours before, so I let it warm up around 1500rpm for a few mins then got on my way, kept below 3500rpm for the first 10-15 mins.. then started taking it a bit further...
Well the needle never left here:
![](http://rx7.pw.cx/photos/templow.jpg)
Now this is the same during the day too, in the sun, about 16 degrees out... and the needle still only came up to here.
I ripped my spark plugs out which are about 4 months old and they were pretty black and brown, this has me thinking im running rather rich... There is also a long patch about 80cm long on my drive behind the exhaust which is all black from warming my car up in the mornings...
1982 with a 3 core radiator, 13B S4 engine (6 port and mods below)...
just wondering what you guys think... is it normal that it is running this cold? I remember a few months ago that it used to usually sit around a quarter... now it barely gets off the lowest mark. are there disadvantages from running this cold?
Cheers and thanks in advance,
Paul.
Its about 6 degrees C outside and I just drove home before, about 20 minute drive, I'd run the car only 1.5 hours before, so I let it warm up around 1500rpm for a few mins then got on my way, kept below 3500rpm for the first 10-15 mins.. then started taking it a bit further...
Well the needle never left here:
![](http://rx7.pw.cx/photos/templow.jpg)
Now this is the same during the day too, in the sun, about 16 degrees out... and the needle still only came up to here.
I ripped my spark plugs out which are about 4 months old and they were pretty black and brown, this has me thinking im running rather rich... There is also a long patch about 80cm long on my drive behind the exhaust which is all black from warming my car up in the mornings...
1982 with a 3 core radiator, 13B S4 engine (6 port and mods below)...
just wondering what you guys think... is it normal that it is running this cold? I remember a few months ago that it used to usually sit around a quarter... now it barely gets off the lowest mark. are there disadvantages from running this cold?
Cheers and thanks in advance,
Paul.
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The gauge does move though and it comes up real slow.. just doesnt come up as high as it would in the past...
Could this be a thermostat problem? maybe its letting water through too fast?
Could this be a thermostat problem? maybe its letting water through too fast?
#7
Originally Posted by H4Inf
The gauge does move though and it comes up real slow.. just doesnt come up as high as it would in the past...
Could this be a thermostat problem? maybe its letting water through too fast?
Could this be a thermostat problem? maybe its letting water through too fast?
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#8
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sorry, its the stock clutch fan. no efan.
regarding the 3core it was on the car when i bought it.
with the clutch fan from memory whenever i bring the revs up, it spins up too... at all times.. is it normal to always spin up faster with more revs, or should it be at a very low speed at all times when the engine is cold? any easy tests?
regarding the 3core it was on the car when i bought it.
with the clutch fan from memory whenever i bring the revs up, it spins up too... at all times.. is it normal to always spin up faster with more revs, or should it be at a very low speed at all times when the engine is cold? any easy tests?
Last edited by H4Inf; 06-27-05 at 10:22 AM.
#9
With my experience running no t-stat, the water temp should be higher than that as in the picture below. thats after an hour of driving on the freeway. Im running a HE 3-row radiator (more fins than the usual mail order stuff but approx $50 more), no t-stat and 50/50 mixture of antifreeze.
Clean the sending unit as well as the male/bullet electrical connection. if that doesnt help, then try a different sender OR install a mechanical gauge (stay off those cheap *** autogage and sunpro with unsealed t-couple).
Clean the sending unit as well as the male/bullet electrical connection. if that doesnt help, then try a different sender OR install a mechanical gauge (stay off those cheap *** autogage and sunpro with unsealed t-couple).
![](http://img.photobucket.com/albums/v365/wack-o-racer/DSC04766.jpg)
#10
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im guessing my tstat could be jammed open because the manual here says its meant to open at 82 degrees C, and that would be about halfway up on the gauge there...
Ill pull the sensor and clean it, clean contacts and pull the tstat and have a look at it tomorrow morning. Anything else I should do?
edit: and ill look into testing the clutch fan... because since you run without a tstat warmer, something gotta be wrong here :P
Ill pull the sensor and clean it, clean contacts and pull the tstat and have a look at it tomorrow morning. Anything else I should do?
edit: and ill look into testing the clutch fan... because since you run without a tstat warmer, something gotta be wrong here :P
Last edited by H4Inf; 06-27-05 at 10:35 AM.
#11
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get a thermometer take your t-stat out and put them in pot with hot water, check if its openning and shutting at the proper temps. sounds like your t-stat is stuck open. I would just change it.
#12
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Originally Posted by WankelingBeer
get a thermometer take your t-stat out and put them in pot with hot water, check if its openning and shutting at the proper temps. sounds like your t-stat is stuck open. I would just change it.
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It definately sounds like the thermostat to me. My car has ate 2 in the past 6 months, stick to the Mazda OEM ones. When I ran without a thermostat since mine messed up, the car wasn't warming up, it was stuck around 50 celsius. After I changed the thermostat, everything worked fine again.
#14
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Originally Posted by darkfrost
It definately sounds like the thermostat to me. My car has ate 2 in the past 6 months, stick to the Mazda OEM ones. When I ran without a thermostat since mine messed up, the car wasn't warming up, it was stuck around 50 celsius. After I changed the thermostat, everything worked fine again.
![](http://rx7.pw.cx/photos/AREAS/thermostat/somethingmissing.jpg)
I'm embarrased to have not noticed this earlier... I guess in summer its better to run without one? This is probably the coldest weather this car has seen in a long time..
It's running at a nicer temperature now, although its about 8 degrees C outside (which really helps keep things cool) - when I accelerate the temp gauge goes down instantly, as the cold air is pushed through the radiator.
![](http://rx7.pw.cx/photos/AREAS/thermostat/thermostat_install%20027.jpg)
I wasn't able to get a mazda thermostat, so hopefully the one I picked up to suit an '88 rx7' - which is approximately what my engine is, will do the trick.
Cheers for all the help and ideas!!
Paul.
#16
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Originally Posted by Elysian
my 74 repu had no tstat when i got it, it just took a long time to warm up, but never had a problem actually getting to temp, and i got it in winter too
#20
Originally Posted by Hades12
Looks like the Recycle port has been blocked.
#21
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![Red face](https://www.rx7club.com/images/icons/icon11.gif)
Originally Posted by 13btnos
Good point alot of people just simply remove the thermostat and don't block the recycle port. You get an inaccurate temperature read when that port is left unblocked with no thermostat. Your engine temperature will actually be higher than what the sensor shows. Since the recycle port is blocked a simple solution for you is get an old thermostat and gut it out. It will be enough of a restriction to get your engine up to operating temps and still flow good to keep things cool on hotter days.
Is it possible to unblock it? Would it be a better idea to leave it blocked and have a gutted thermostat in winter / no thermostat in summer? Or should I unblock it and have a normal thermostat?
Are there performance advantages from having no thermostat? Less resistance on the water pump?
Sorry about all the questions but I really want to learn all this stuff
![Wink](https://www.rx7club.com/images/smilies/wink.gif)
Another picture if it helps with explanations:
![](http://rx7.pw.cx/photos/AREAS/thermostat/thermostat_install%20017.jpg)
TIA
#22
See in that picture where there appears to be a brass plug well that is the recycle port. If you think of the system when the thermostat is closed the 1/2in hole is open and allows for hot coolant to recirculate into the engine to speed up warm up. Now when the thermostat opens it closes that hole and forces all the hot coolant out the engine and go to your radiator to be cooled off. Now if that hole is left open the whole time you have to remember that the pressure from the water pump is going to force "cool" coolant through that hole and give you a false reading of temperature. Think of where your temperature sensor is at it is right below the thermostat and right above that 1/2 hole. So you are getting a cool reading at the sensor but the actual temperature in your engine will be higher. Hope that makes sense to you. Since someone already plugged that hole I wouldn't worry to much but if you put a thermostat back in there I would unplug that hole. It will help speed up warm up. I personally like a thermostat it keeps the engine in it's running temperature. If you decide not to unplug that hole then I would recommend gutting a thermostat out to give it just a little resistance but warm up time might be slightly longer. Just my thoughts and experience. Hope it helps.
#23
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Thanks so much for the explanation!
I'll see if I can get the plug out of there asap, and get a proper gasket while I'm at it for the thermostat housing.
I really appreciate the explanation!![Big Grin](https://www.rx7club.com/images/smilies/biggrin.gif)
Cheers,
Paul.
![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
I really appreciate the explanation!
![Big Grin](https://www.rx7club.com/images/smilies/biggrin.gif)
Cheers,
Paul.
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