Where is all my COOLANT going?

[ronsam2006]

My car keeps eating up all the coolant. I have gotten a block check at the radiator shop and my head gasket is fine. I replaced the thermostat. My cap is fine as the shop checked it. But almost every two to three days, the coolant reservoir is empty and about 1/4 of a gallon needs to be filled into the radiator fill cap along with the reservoir. I properly leak it until the thermostat is open and the car is up to running temp. I don't have any leaks...HOWEVER, there was this leak from under the car, under the driver foot(from the underbody), which i sealed up with RTV. The other day, after running it hard, it spit some coolant out from the overflow tube. I have nooooooooooo idea. PLEASE HELP ME!!!

 

[ronsam2006]

One thing that drives me nuts is that there is no gasket between the tstat housing and the head. My car has a pinhole leak no matter what I do. If i hadn't been looking for something else I would have never noticed it. You can get these dyes at the auto parts store that fluoresce, you put it into your coolant, drive for a while and then check it with a black light in the garage at night Hope that helps.

The new head I am building I will have the head/tstat housing machined flat so that hopefully it will have a perfect seal. I have seen this on several DSMs. Also if your coolant leaks onto something hot and vaporizes you wont see a leak on the ground. I believe the dyes will leave a residue but ask your parts guy to make sure.

Thats a great idea!!!! Thanks a lot. Im going to go check that out at my local store. Actually, I replaced the tstat only a few weeks ago. After the third try of putting proper rtv, it sealed finally, but maybe it could just be that. Let me just go around the block and do a couple of good pulls and get back at you. Thanks a lot for the idea.

 

[ronsam2006]

Ok so a few minutes after posting, I took it out for a good run. Did a good pull a few times from 2nd to 4th shifting at 6200rpm. When I stopped, a little more than a hand full of coolant/water came out of the over flow tube. Then I did this a few more times, it happened again a couple more times same amount of water. The reservoir is still full. Im thinking that it does this, then when I normally driving, it sucks all the coolant out from the reservoir and leaves it empty. I do push it once every time I drive just a little bit, but why does it keep pushing it out the dump tube???

 

[andy4g63]

I had another type of coolant eating motor, guess what? It was FIAV gasket and happened right after i replaced me TB with another one from throttle bodys.com . It had a brand new gasket and even though was leaking. The worst part is water is not compressable, but thank god at the same time I was replacing my IM and I saw poodles of antifreeze inside intake manifold, so I bought FIAV bypass plate, installed it and got rid of coolant lines to and from TB. It wasn't missing a lot, but still causing the car to run a little hot.

 

[2gAWDGUY]

I think your cooling system isn't pressurized.

 

[ronsam2006]

What exactly does that mean? You mean the cap isn't properly holding pressure? The radiator shop checked that, said that the cap was fine.

 

[gixxerdrew]

I think what he means is that if you have a leak somewhere, even pinhole sized your system doesnt get up to pressure. At a lower pressure water boils sooner you get hot spots and so it will kick coolant out easier. Worry about the leak first and then worry about the coolant pushing out. Fixing one *may* fix the other.

 

[eric62810]

did u look for bubbles in t/stat housing when the car is idling??? if u did and no bubles rev it a couple times and see if it happens if it does than its the h/g ive had the same thing happen to me several times when i had the 1.8 in my car suck it dry when normal driving ang spit it out when driving hard

 

[ronsam2006]

did u look for bubbles in t/stat housing when the car is idling??? if u did and no bubles rev it a couple times and see if it happens if it does than its the h/g ive had the same thing happen to me several times when i had the 1.8 in my car suck it dry when normal driving ang spit it out when driving hard

Every time I refill coolant in the fill cap, I always see bubbles when the car is started...im like THAT MUCH AIR???

How can I find a small leak like that?

 

[TheWanderer]

Just my 2 cents worth..

I agree with the rest of them that it sounds like you aren't at the right pressure in your coolong system. Start with the easiest fix first: for about $15 you can replace the radiator cap with new one that has a pressure release valve on it. Even though your system was tested, it can still be a faulty cap. I've already had it happen, and I blew the head gasket/warped the head.

Also, check your lines from the TB. one runs to the thermo housing and the other run down to what looks to be a heater core line (not sure on that) to make sure that the hose clamps are tight and that the hoses are in their respective spots.

If it makes you feel any better, you aren't the only one going through coolant issues at the moment.Don't beat yourself up over it, it'll come to you eventually. It could be worse, you could be in my shoes. My coolant boils in the upper hose after highway driving, and the car isn't overheating...i can actually hear it bubbling when I get out of the car.

 

[vancitydsm]

Ronsam sounds like ## cap bro.. or ## getting compression into ## coolant and its over powering the cap.. try replacing the cap for fun.. i had a problem like that i was certain my head was leaking.. but no, rad cap.. the purpose of having the temp control to the " heat " selection is that there is a valve which open/closes allowing flow or not to heater core.. its on selected cars but i dont know if it applies to our dsm's its just a lesson to use generally and it doesnt hurt. if the valve is open u wont bleed any air which is in the heater core..

 

[eric62810]

is there steam or smoke from the bubbles if so its the hg

 

[Maxboost1010]

Have you tried doing a cooling system pressure test, set it to 20 psi and if you can then tell us how long the pressure holds, at about 20 psi even a small leak will normally become apparent. Also when you are driving try setting your heat to max and on defrost, and let us know if your windshield fogs up.

 

[awdtsi724]

if its leaking by your feet sounds like the heater core

 

[ronsam2006]

Just my 2 cents worth..

I agree with the rest of them that it sounds like you aren't at the right pressure in your coolong system. Start with the easiest fix first: for about $15 you can replace the radiator cap with new one that has a pressure release valve on it. Even though your system was tested, it can still be a faulty cap. I've already had it happen, and I blew the head gasket/warped the head.

Also, check your lines from the TB. one runs to the thermo housing and the other run down to what looks to be a heater core line (not sure on that) to make sure that the hose clamps are tight and that the hoses are in their respective spots.

If it makes you feel any better, you aren't the only one going through coolant issues at the moment.Don't beat yourself up over it, it'll come to you eventually. It could be worse, you could be in my shoes. My coolant boils in the upper hose after highway driving, and the car isn't overheating...i can actually hear it bubbling when I get out of the car.

Hmm..where can I find this pressure release valve radiator cap for my car? That sounds interesting...is this similar to a pressure cooker?

 

[leathaltsi]

I had a leak from my oil filter hoses and when I drove the car it blew back to my floor boards just put the car up on ramps and leave it running sit there and watch if you dunt see anything than it might be going out your tailpipe smell your exhaust

 

[eric62810]

If your seeing alot of bubbles all the time u might have blown the hg between one of the cylinders and a coolant jacket it wont show up on a pressure check as compression on a cylinder is higher than the pressure that the coolant system hold thats what it def starting to sound like to me..