Radiator fan and coolant

Aoiex · Post by **Aoiex** » 30 Jul 2016, 17:18

I was hoping maybe someone could help me out a bit. My fan isn't turning on at all. Before all these problems happened my fan wouldn't stay off but now it won't turn on. One of my heater hoses exploded so I changed both of them and flushed my coolant system. What is happening is that my coolant is boiling into and out of my reservoir, at the same time my fan will not cut on. I have also replaced my thermostat because I thought that would be it but it wasn't. I was thinking a relay of some sort? But I couldn't find one. So if anyone could help me that'll be great! She's been off the road for almost 3 months now

Post by **oragex** » 30 Jul 2016, 17:40

Did you also replace the coolant temp sensor near the thermostat? The regulator that's fixed on the fan assembly might be toasted. In order to save postage money, time and hassle, I cut the two wires to the fan motor and replaced the regulator with a used unit from a seller who was nice enough to chop it off from a used fan assembly.
Then soldered the two wires on the new regulator.

Aoiex · Post by **Aoiex** » 31 Jul 2016, 09:56

Could you provide a picture for the coolant temp sensor? And is it a hard replacement? I'm sure my fan is a problem with it not turning on but my coolant just bubbling out of the reservoir doesn't make sense. It can idle all day but after you drive it and stop that's when it'll bubble out. Also I did notice when I flushed it out the water was coming out boiling hot, don't know if that could help any??

Cees Klumper · Post by **Cees Klumper** » 03 Aug 2016, 09:09

Replacing the coolant temperature sensor IS in fact a tricky job, since you will risk breaking off the small plastic tube that routes coulant back to the overflow tank, and is located on the thermostat housing, in which is also located the temp sensor. It's all behind the timing belt cover, VERY tight quarters to work in. These plastic tubes get brittle and it doesn't take much to break them off. Lots of info in this forum on this issue. Get a replacement thermostat housing / thermostat / temp sensor / gasket, original Volvo (this complete set sells for a bit over $120 or thereabouts as I recall, from the usual parts suppliers).

Aoiex · Post by **Aoiex** » 06 Aug 2016, 06:31

As I was trying to take off the thermostat housing one of my screws got striped.. I don't know what to do at this point.. I was playing around with it a bit and tried unplugging the sensor the make the fan come on, it didn't work. I don't know if that's a thing that'll happen? Today I bought some more coolant to test my gauge in my car and found out it doesn't work. I filled the coolant then squeezed the top radiator hose to get air out for about 5min. After doing that I let the car sit for around 10min. Went back outside coolant was out of the tank so filled it and almost instantly was gone. The hose was hot to the touch. Checked inside the car and the gauge was still not working. I don't know why it's heating up so fast, why my fan isn't turning on, and where is all my coolant going? Surely 5qts with some still in the engine is enough? Would really love to get this car running.. again... Anything will help