I'm wondering what normal temp is required for the radiator fan to automatically turn on. My problem is that when it was idling a few days ago the coolant decided it was not going to stay locked up in my series of tubes and wanted a breath of fresh air and pavement, i.e. boiled a bunch of it out. I got the low coolant level warning and drove to the nearest fast food joint and added some water to the coolant. I'm getting white vapor coming out the reservoir as well. We didn't have the attachment to do a coolant pressure test but I am going to try to look into that soon today to see if it would be possible. If anyone also has a schematic for the radiator/cooling system or know where I can get one it might be helpful.

One of the things we are suspecting is that the thermostat might need replacing or maybe the head gasket is failing(Just to toss out some ideas). I'll test if the fan comes on with A/C here in about 30 minutes to get that test out of the way.

 

The fan should come on when the temp gauge reaches the 2/3 to 3/4 of full scale. Get the coolant mix in your system back to the 50/50 ratio ASAP - plain water will corrode the works.

Check the coolant, and see if you have oil in it. Also, check your dipstick and make sure there's no coolant in the oil

 

Fan still works with A/C on. I have checked both the coolant and oil, no sign of any mixture. There is still coolant in there just a bit lower than the 50/50 mixture. Will check asap and try to correct the mixture.

I forgot to add that when it boiled over the temp gauge hadn't even hit 1/2 yet. One of the reasons I was thinking that maybe the pressure is wrong.

 

Hmmm, sounds like an old-fashioned check is in order.

With the engine COLD, remove the radiator cap. Start engine, and as the engine warms, look for bubbles in the coolant (indicative of a blown head gasket). Second test is to smell the exhaust fumes, looking for sweet/fruity/alcohol smell. Final test is a compression test. All cylinders should read roughly the same

 

Boiled over or pressure forced out past the cap. Have cap tested and replace if need be.

 

Did the old fashioned except compression check on the engine and seemed to be no problem. May have to do that tomorrow at school unless my buddy has his compression kit with him. Was going to do a coolant pressure test but dont have the kit.

 

I think you are going to find that you have a slow leak somewhere in your system. Probably a rubber hose or maybe the water pump. It simply got hotter because the coolant got low, maybe not low enough to trip the coolant light, but a little low, just enough to raise the temp and cause the system to not hold pressure which will make a little more steam.

 

The strange thing was I had checked the coolant a few days before and everything was at the correct level(all fluids). Have tried letting it idle again since then but no reproducing yet. I have been wanting to make sure that the engine compression was correct, which if I can I will do here soon. I'll have to wait until the 11th I think to rent the tool.

 

check the plastic radiator end caps for cracks and where the plastic meets the metal of the radiator. Note that leaks here can have the leaking coolant blown behind the radiator so look for coolant residue behind the radiator

 

Didn't see anything when I checked but I am going to check again in the morning when I get off of work. Does anyone know what operating temp in degrees would be? Have a temp gun I have access to would like to check that as well.