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Antifreeze pouring out...and stopping

I need help to figure out why my 1999 Taurus was gushing out antifreeze yesterday.



I've been driving this car for a few months. Since I've gotten it, I've realized I lose a gallon of antifreeze about every three weeks. I noticed a small drip in the driveway, and can see the point where the fluid drips from the underbody at the front left (the driver's left) corner of the car. It comes from under the radiator's left edge. Because of a underbody panel, I can't see the leak directly. I tried a stop-leak product, which did little to help. Obviously, these hot days this summer have made the issue worse.



Yesterday, however, was another situation altogether. It was 75 degrees outside, and rained at noon. The car sat at work all day until I ran an errand at 3PM, traveling about three miles for a half an hour. No problems so far. At 4:30PM, I drove a mile in 15 minutes. When I returned to my car 15 minutes later, there was a gushing flow of antifreeze coming from the front left. It appeared to be coming from the same spot as before, but instead of a small drip, this was flowing at the same rate as if you were pouring out a can of beer.



Instead of taking time to see where the fluid was leaking from, I jumped in the car and tried to race home. I didn't want to get stranded, and with the heater on high, I made it the few miles to my house. The car sat overnight, dripping out a small amount more.



This morning, I filled the empty overflow tank with straight water (no sense in having antifreeze pour over my driveway) and waited. No gush of water. I turned the engine on and let it run for ten minutes. No gush of water. I can't find the source of yesterday's big leak. And I'm puzzled as to why the car would pour out fluid one day, and not leak a drop the next.



I'd appreciate any thoughts.



Gabriel Mann

Comments

  • edited September 2010
    If the radiator is now empty, that could explain the end of the leak.
    Filling the overflow tank is not going to replenish a radiator that is dry.

    Once everything is cooled down, I suggest that you remove the radiator cap and see what the level of coolant is. I suspect that you will find none.

    In addition to refilling the radiator and fixing the radiator leak, I suggest that you remain vigilant for signs of a breached head gasket and for other signs of engine damage.

    Driving the car home while coolant was gushing out was...not a wise thing to do. You could have caused some serious damage to the cylinder heads, cylinder walls, bearings, etc by driving a car whose engine was running very hot.
  • edited September 2010
    Thanks for the reply.

    If the car has an overflow tank and the refill cap is on the tank, is there a second "radiator cap" on the actual radiator body? Or is the tank cap the one you're referring to? I did check that after letting the car cool, found nothing, and refilled with water.

    How long would I need to let the car run before the refilled overflow tank filled the radiator and started leaking again. I had the car running for ten minutes, and could see the fluid moving in the transparent tank. Do you think I just haven't given it enough time?

    I understood the risks I was running by driving without fluid, but I assumed that adding more fluid at the point where it started gushing would just pour out as well. I wanted to try to get home and not have to add a tow truck bill to my mounting costs. The temperature gauge never rose above half-way.
  • edited September 2010
    An overflow tank is usually not an integral part of the cooling system but the reservoir on your car is. Filling that reservoir fills the cooling system. Now, how much damage is done? What can you do? What should you do? I'll throw a suggestion at you. Remove the splash guard and fill the reservoir with water and check the source of the leak. Very possibly it is the radiator end tank. If so you will want to know if the engine is damaged before attempting to repair the radiator. Post back the source of the leak.
  • edited September 2010
    An excellent suggestion. I concur.

    You could even perform your own pressure test if you're "hands-on" enough to rig up a hand pump (or bicycle pump) to the radiator hole and put a little air pressure in it. It won't take very much, 15 psi is all you want to use. The gages on most hand pumps are plenty accurate enough for this test.
  • edited September 2010
    What's the difference between an overflow tank and a reservoir? I'm referring to the white plastic tank with a cap with instructions for engine coolant on it. There are two hoses on top, one heading to the radiator and one coming from the engine. This is the overflow tank, right? Is there a second holding-tank for antifreeze? If so, where?

    Getting the splash guard off is a little puzzling. I'm not confident in my ability to get body panels back on if I manage to get them off.
  • edited September 2010
    I'm hands on, but not that much. This sounds like the guys in Apollo 13 trying to rig an air filter out of a space suit and duct tape.
  • edited September 2010
    An over flow tank is a catch tank for the over flow valve on the radiator. There is no pressure involved on such a tank. It is of marginal use on most vehicles. Many vehicles have reservoirs today that are integral to the cooling system and the cooling system is filled through the reservoir. Such a reservoir has a fill line and allows for expansion, eliminating the need for an over flow tank.

    If you can't get the guard off it will be difficult to see the leak. You might consider getting into a shop soon. And with the high probability of engine damage it would not be advisable to drive far.
  • edited September 2010
    Gotcha. In that case, anywhere I've referred to an "overflow tank" then I meant reservoir.

    I drove it around the block to try to get the fluid flowing again. With the water I added this morning, the level is still well within the fill line area. The water also mixed with some fluid left in the system, and judging by it's green color, I'd guess I'm at a 75:25 water:antifreeze mix. I'm confident I can get to a shop without doing more damage...but I've got to wait until Tuesday.

    I may try the splash guard again.
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