Is it the head gasket, the thermostat or the water pump???

Question

I have a 96 Infiniti G20, everything was doing fine till this morning when I heard a weird sound (metal knocking like) and noticed that needle of the temperature guage was rising(75% hot).I parked the car, pulled up the hood and found out that the upper radiator hose had poped up from the radiator. As I always have a gallon of water in the trunk of my car, I put the hose back, tried to fill it out again but the radiator kept on SPRAYING THE WATER OUT. I was wondering if it would have been better to wait until the engine had cooled off before doing so.

Thank you in advance for your expertise or suggestions

Answer 1

ok...first, you don't want to put cold or cool water/coolant into an overheated engine. This could crack a head or block because of the difference in temp. You might want to check to see if your thermostat isn't stuck closed (which is what it sounds like to me) . when you was putting the water in, it sounds like the the stat was closed and the water couldn't circulate thru the motor. I would change the thermostat before anything else. (one way to check the old one is to take it out, put it in a pot of water. set the burner on your stove to boil the water. just before it starts to boil the stat will open...or pop...same thing. if this happens, your stat is good)

Answer 2

I'm curious as to where the radiator is puking the water from. Is it coming from the overflow tank, or is it flowing right back out of the fill port? Was the car running or off?

MORE INFO!

Answer 3

You must wait until everything is cooled off before adding water.

The cooling system is pressurized, you need new hoses and hose clamps.  Replace them all at once, the other hose will likely fail shortly.

It is highly unlikely that there is a problem with the head gasket, the thermostat or the water pump.

Answer 4

From that description, it doesn't sound like there's any reason to think there's a problem with any of those things...yet. Make sure the hose is on correctly (and that it's in good shape) and the system is filled properly and THEN see if there's a temp problem before you start worrying about anything else.

Answer 5

First thing.never add coolant/water directly to a hot engine. You should add it through the reservoir tank. It is hard to tell exactly how much damage you have by the description. The hose may have come off from a pressure buildup due to a blockage. It also may have been loose. Have the hoses ever been replaced? You can tell if you have a bad head gasket by checking the oil. If it is muddy looking and contains water droplets, you have a blown gasket.  

Answer 6

Rudy is right... none of the above can cause "spraying water out".... what color smoke is coming out of the tail pipe if any? Grey = bad head GASKET

Answer 7

Can't tell from that description. You just said what happened, not any other symptoms. It could just be the hose came loose for some odd reason. Are you sure the radiator isn't plastic and has a crack?