Overcooling
#1
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Overcooling
I recently did a coolant reroute, and now I'm having an overcooling issue with my car.
Cooling system:
-Koyo 55mm rad
-190 deg t-stat
-FM oil cooler/thermostat
-OEM oil cooler
-Beatrush undertray
-water temp sensors in the BEGI spacer
-single 12" slim fan
-deleted the t-stat neck from the front of the motor
-oil temp sensor in the sump by the drain plug, pass side
-70/30 water/coolant mix, with a bottle of redline water wetter
-no other duct work
I'm seeing water temps no higher than 180 while I'm on it (drops down to 160 during cruise), and oil temps around 150. Even sitting in 90 deg traffic the temp barely came up to 190 (I have my fan set to come on at 194). I'm still using the OEM oil cooler as I'm running the water line for my turbo off the IACV water outlet.
Should I block off a portion of the radiator? I've never been in a situation like this before. This is one of those problems every other turbo miata owner is going to hate me for, haha.
Cooling system:
-Koyo 55mm rad
-190 deg t-stat
-FM oil cooler/thermostat
-OEM oil cooler
-Beatrush undertray
-water temp sensors in the BEGI spacer
-single 12" slim fan
-deleted the t-stat neck from the front of the motor
-oil temp sensor in the sump by the drain plug, pass side
-70/30 water/coolant mix, with a bottle of redline water wetter
-no other duct work
I'm seeing water temps no higher than 180 while I'm on it (drops down to 160 during cruise), and oil temps around 150. Even sitting in 90 deg traffic the temp barely came up to 190 (I have my fan set to come on at 194). I'm still using the OEM oil cooler as I'm running the water line for my turbo off the IACV water outlet.
Should I block off a portion of the radiator? I've never been in a situation like this before. This is one of those problems every other turbo miata owner is going to hate me for, haha.
#3
Something may be weird with your reroute - can you show us pictures? Or give a lot more information on what you did?
It sounds like you are bypassing a lot of water somewhere past the thermostat. I fucked up like that and had the same symptoms with my first reroute when I originally put it together.
It sounds like you are bypassing a lot of water somewhere past the thermostat. I fucked up like that and had the same symptoms with my first reroute when I originally put it together.
#7
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That's well below normal IMO.
Standard reroute using that big SUV hose and the BEGI spacer/KIA waterneck.
I agree, hence why I started this thread. What is the stock T-stat rated at just out of curiosity? I have a 190 in there right now. The fan is set to come on at 194, and as it doesn't get over 190, it doesn't need to come on. Switching to a higher T-stat and changing the fan to a higher temp isn't going to do anything for me.
Nope, still have it.
How did you secure it? I have some scrap aluminum sheet laying around I was planning on using, if that seemed to be the consensus.
Something may be weird with your reroute - can you show us pictures? Or give a lot more information on what you did?
It sounds like you are bypassing a lot of water somewhere past the thermostat. I fucked up like that and had the same symptoms with my first reroute when I originally put it together.
It sounds like you are bypassing a lot of water somewhere past the thermostat. I fucked up like that and had the same symptoms with my first reroute when I originally put it together.
Nope, still have it.
How did you secure it? I have some scrap aluminum sheet laying around I was planning on using, if that seemed to be the consensus.
#8
Mighty, let me be clear about something.
If you aren't putting water through the rad (thermostat is closed and water shouldn't still be going by it), you shouldn't be getting much cooling from the radiator. I mean, you'll get some by default, but it shouldn't cause what you are talking about.
This was the problem I had. I had a hole in my thermostat to bypass water, and it caused me all sorts of headaches as a result.
If you aren't putting water through the rad (thermostat is closed and water shouldn't still be going by it), you shouldn't be getting much cooling from the radiator. I mean, you'll get some by default, but it shouldn't cause what you are talking about.
This was the problem I had. I had a hole in my thermostat to bypass water, and it caused me all sorts of headaches as a result.
Last edited by blaen99; 08-21-2012 at 04:58 PM.
#12
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Mighty, let me be clear about something.
If you aren't putting water through the rad (thermostat is closed and water shouldn't still be going by it), you shouldn't be getting much cooling from the radiator. I mean, you'll get some by default, but it shouldn't cause what you are talking about.
This was the problem I had. I had a hole in my thermostat to bypass water, and it caused me all sorts of headaches as a result.
If you aren't putting water through the rad (thermostat is closed and water shouldn't still be going by it), you shouldn't be getting much cooling from the radiator. I mean, you'll get some by default, but it shouldn't cause what you are talking about.
This was the problem I had. I had a hole in my thermostat to bypass water, and it caused me all sorts of headaches as a result.
The FM kit has a t-stat, so until it gets to a certain temp, the oil cooler is essentially not there. I looked again last night and the oil temps were up around 170, not 150 as previously stated.
#13
Well if your T-stat doesnt open to 190 on either the coolant or the oil, neither of them should even be flowing through the rad/cooler. The only thing that really causes the car to never heat up is a stuck open t-stat, or the sensor not reading right. It your rad/oil cooler were doing too good of a job your temps would just be stuck at the thermo opening temp.
Or the temp sensors arent working right. But both sensors are reading funny at the same time, so its very unlikely they both died. It must be a ground offset issue that just popped up. Are these two sending units grounded to the normal sensor ground or just to the engine? And does your coolant gauge match the engine temp reading in the standalone?
Or the temp sensors arent working right. But both sensors are reading funny at the same time, so its very unlikely they both died. It must be a ground offset issue that just popped up. Are these two sending units grounded to the normal sensor ground or just to the engine? And does your coolant gauge match the engine temp reading in the standalone?
#16
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Well if your T-stat doesnt open to 190 on either the coolant or the oil, neither of them should even be flowing through the rad/cooler. The only thing that really causes the car to never heat up is a stuck open t-stat, or the sensor not reading right. It your rad/oil cooler were doing too good of a job your temps would just be stuck at the thermo opening temp.
Or the temp sensors arent working right. But both sensors are reading funny at the same time, so its very unlikely they both died. It must be a ground offset issue that just popped up. Are these two sending units grounded to the normal sensor ground or just to the engine? And does your coolant gauge match the engine temp reading in the standalone?
Or the temp sensors arent working right. But both sensors are reading funny at the same time, so its very unlikely they both died. It must be a ground offset issue that just popped up. Are these two sending units grounded to the normal sensor ground or just to the engine? And does your coolant gauge match the engine temp reading in the standalone?
hence why I started this thread.
#17
You could have tweaked something fumbling around by the head. If it was only the coolant sender reading low I'd say it could be just an air pocket around the sensor. But since its both reading low, and they're both ground to block and not to the normal sensor ground the best bet is you'll find the temp sensor in MS working properly and its a ground offset issue. Do both gauges read ambient when the car has sat overnight?
#18
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170*F is too low, still. I would prefer to see 200*F in every day use.
#19
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Not entirely true. If the oil cooler were totally bypassed, the oil pressure drop that would happen when the thermostat opened would kill motors. The Mocal adapter maintains ~10% flow through the oil cooler core to keep oil pressure up and eliminate that dangerous drop. Regardless of where the thermostat opens up (it's like 180*F IIRC), covering the core with a couple of strips of duct tape will bring oil temps up.
170*F is too low, still. I would prefer to see 200*F in every day use.
170*F is too low, still. I would prefer to see 200*F in every day use.
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