Where's the coolant going?

[Sonyman]

Question, if your radiator hoses is good, heater core/hoses is good, thermostat is good, resivor bottle is good, radiator cap is good, radiator is good, no signs of milkshake in the oil, no leaks of coolant anywhere but the car will run hot after a week of driving. Check under the hood the radiator is bone dry but the resivor bottle is full. What the heck is what with that?

[SuzukiGhostRider]

I would say time to reinspect. You're losing it or burning it somewhere! If you're absolutely SURE it's not leaking , then it MUST be burning. Once your car gets warmed up, go and smell the exhaust coming out of the tail pipe. I'm sure you know what warm antifreeze smells like. Sickly sweet smell. If you smell it there's your answer. GL.

[Sonyman]

you're not suggesting a blown head gasket because it runs so smooth without a miss you can sit a glass of wine on top and it wont fall just like the Lexus commercial.

[d.o.h.c]

Thats not completly true at all. The 3.4 DOHC system you have to bleed the air out of the system. If you dont do this then you will constantly put more and more water/anti in your overflow tank cause the air is bleeding out by itself. It could still be air, you just need to check and make sure that there are no small leaks next to exhaust pipes, cause once it hits the exhaust it just disappeares. Check all around the car, get the car warm open the hood check make sure you dont hear any sizzling. If your good there, check make sure no white smoke out the exhaust. If your not sure about that, either check compresson or put a VAC gauge on the car, that will tell you if you have a bad head gasket right away. If everything checks out its either air, or a small leak.

M

[SuzukiGhostRider]

I sincerely doubt it's air. He said the RADIATOR is bone dry after a week, and the res bottle is FULL. The radiator alone should hold close to 3 quarts, 2 anyhow, of coolant. If he has THAT big of an air leak ,he's got a huge coolant system! Besides ,the car obviously isn't sucking coolant out of the overflow as it should be. You definitely have a leak or are burning it. And bad heads/headgaskets won't always make the car run rough right away. I would check for a leak throughly first. GL.

[55trucker]

You didn't mention if you've done any recent work that would need the cooling system drained....if you have , and as stated above you didn't properly bleed the system look for the small bleeders in the cooling system (one is in the heater return pipe next to the master cylinder and the other is next to the forward cylinder head in the rad cooling return pipe)...they are small 7mm? brass nuts that can be loosened to get the air out while the engine is running and the cooling system pressurizes. If you've not opened the system recently you might consider getting your coolant system pressure tested to see if it all is normal.

[d.o.h.c]

If the head gasket was leaking, a VAC gauge would show it. To confirm that you can run a compression test as well. I doubt that your head gasket is gone. I do have one question for you, does the low coolant light come on and off? If so I would say its 90% air. Mine is doing it now cause I have not had the time to bleed the system. The most prone places that leak on these cars are under the plenum. There is a hose that attaches to the plenum, check that. Mine use to leak there and until I opened the hood right after I was driving, I never would have found it. It just drips and hits the crossover and burns up. You will never see a leak on the ground. First check for leak, really check for leaks, if all checks out, check your VAC, if that checks out you CAN run a COMP test, but more than likely your OK. I would then say its AIR. Thats what I say. I have only been working on these cars for 8 year at about an 1hr a day. These motors break all the time, so get use to it, and I have a turbo so it makes it just that more difficult.

M

[Sonyman]

ok, ok, i hear what you all say... but could you all also say that because of air in the system, it would cause the radiator not to replenish itself from the coolant bottle? A coolant system in a car is somewhat easy to understand but if the problem causer is hidden or not out in the open then that makes it more difficult.

[d.o.h.c]

The water cooling system in the 3.4 DOHC is very complex. If you fill up both the radiator and the coolant tank and you dont bleed the system there is a very big air bubble that is messing up a lot of things. That air bubble can actuall cause the temp gauge not to work right and that can mess with the computer, not very likely but can happen for sure. Like we all have been saying, you need to confirm that there is no other problems, IE: leaks, burning, bad compression,etc. If all those check out 100%, I would look at air in the system.

What I like to do to get all the air out of the system is first, open the valves so that the air can expel when you are adding coolant. Then start filling the coolant. Get the coolant as high as you can get it, most of the time you will have to fill, wait, fill and wait some more. Once you get it high enough put some extra in the recovery tank. Now start the car. You should have the radiator cap on as well. The car needs to get pretty warm, warm enough for the T-Stat to open. During this time you can squeeze the hose(top radiator hose) to push the air out. Then just let the car get warm. Now your low coolant light might come on, thats ok. If that happens just watch the temp gauge and make sure it does not go crazy. The T-Stat will open and the water level will go real low. At this time you should be watching the valves for a streaming flow of coolant. Once you get coolant flow, close that valve. Once both valves are done, shut the car off, open the hood and go to sleep. Get up in the morning fill the remaining in the radiator and put a little extra in the recovery tanks and your done.

M

[Sonyman]

Go to sleep huh? i like that, ok i'll look into it. Thanks again guys.

[pocket-rocket]

ok, ok, i hear what you all say... but could you all also say that because of air in the system, it would cause the radiator not to replenish itself from the coolant bottle? A coolant system in a car is somewhat easy to understand but if the problem causer is hidden or not out in the open then that makes it more difficult.

A bad cap can make the radiator go dry and not refill itself when the engine cools. I would also check and make sure the overflow tank tube going from the radiator itself isn't plugged too.