Coolant temp light/ alarm going off

[GVations]

I drained and changed the coolant in my 2007 l185 New Holland skid steer and also pressure washed it. The coolant temp light and alarm has been coming on since then. It's definitely not over heating. Not sure if a sensor got hit or needs to be reset after changing coolant or possibly a wire hit when I was power washing. Any help would be greatly appreciated

 

[Shanmar]

The number 4 is pointing to where the temp sensor is. You can check the wiring from it. Make sure coolant is full. Maybe take sensor out to make sure there is coolant is there and there isn't an air bubble trapped from when you changed it. (Not sure how likely this is, but know it can happen with air to water intercoolers.) That's the first ideas.

 

[GVations]

I did check the wiring, everything seemed to be tight, looked like it may have had a bit of corrosion so unhooked them and hit them with a wire brush but no luck. I'll try pulling the sensor tomorrow to see if there's any air bubbles. Would you top it off from the sensor if for some reason seems low? Appreciate the help!

 

[GVations]

@Shanmar I have to replace the fan bearing tomorrow too, are you familiar with those at all? We were going to disconnect radiator and hydraulic cooler to get to the fan, wondering if there is an easier way, or if that's the best way to access it.

 

[Shanmar]

Never tried to just get the fan out. Usually was going deeper. Maybe you can loosen up the bolts/take some out at the bottom corners of the cooling package and lean the whole housing back enough. Take the shroud loose. And then with enough contortions take the 4 bolts out of the end of the fan and then the bolts that hold the fan mount. Maybe? If not, it's not ungodly to take whole cooling package off if you have 2 people. Just sucks to loose the coolant and some oil (maybe a fair bit). We never tried taking just the oil cooler and radiator out of the housing. Something tells me there are some bolts that are real hard to get to.
As far as topping off, I would expect that if the radiator is full, it should push the air out (if any) and then start leaking coolant pretty quickly since the level in the radiator should be higher than the sensor.

 

[GVations]

Ended up just pulling the radiator and oil cooler just to make it easier to work. Had to pull the shroud off to get to the four bolts ( in each corner) that held the oil cool in. Feel like you'd have to pull it to get the fan out although I was looking at the diagram on messinicks and it mentions a hinge on the cooler, so maybe you could hinge it from the hydraulic lines ( that attach to cooler) to be able to access the fan. Not sure. We got it done though.
Took off the sensor, the light/alarm was on when it was first started but went away after it got warm. It was getting late so had to call it, I'll check it out tomorrow/ Monday to see if it comes back on

 

[GVations]

@Shanmar so the coolant temp light & alarm are still going off. After changing the fan bearing and taking out sensor to let air bubbles out the light was off when I first started it then came back on. I plowed for 5 hours yesterday and it was on for most of the time but would shut off and come on/off. Not sure if this matters but I noticed if i just sat in machine, buckled seat belt, started machine and unlocked the parking brake before the coolant temp light came on, the alarm wouldn't go off. Didn't work all the time but majority.
What would you suggest to try next? Replace the sensor?

 

[Shanmar]

If you unhook sensor and keep wire from touching anything what does it do? I expect it to say nothing or cold/lo temp. And if it's grounded/touching metal, I think it will say high temp.

 

[GVations]

@Shanmar i'm heading down to machine now but the instrument cluster is pretty basic, it doesn't have a temp gauge.

 

[Topper1]

Engine is NOT actually overheating??? Not a simple thermostat stuck closed???
If that isn't the case, I'd strongly suspect a bad sensor or grounded sensor wire.
***Sensor is a linear resistance curve 4300-180 ohms, decreasing with temperature rise.
"overheat warning" usually occurs at around the 80-100 ohm value. ***
Sensor testing
- Disconnect sensor wire.
- Sensor pin to ground (60*F +/- 4300 ohms, 212*F +/- 180 ohms)
**** At running temp, if sensor reads less then 80 ohms, it has most likely failed****
- wire to ground should have +/- 12volts to ground while disconnected from sensor, key on.
-possibly got water into the sensor itself, Unlikely, but have had it happen to myself on a couple of occasions.

If you were aggressively washing inside the cab, you may have gotten the control panel wet.
I do wash my interiors carefully on occasion, but have never had a failure of the control panel.
***We are all extremely careful NOT to blast our interior electronics with washguns I would hope.

 

[Shanmar]

Pretty sure these use a temp sensing switch and not a resistive sensor. So, either open or closed.

 

[Topper1]

2007 L185 uses the standard Case/ New Holland temp sensor #A166057 which is a thermistor (temperature variable resistor), NOT a simple on/off temperature switch.
The A166057 sensor also applies to upgrade models with gauges for Case & New Holland skid steer models from late 2006 - early 2014.
The sensor is read by the control panel and triggers the overheat warning, supplies the reference for the temperature gauge & initiates the manifold cold start grid heater on later models.