Crazy coolant
Many of you might remember my post a little while ago about my heat taking forever to get hot, even after the engine is at operating temperature. I thought the issue was low coolant, but no some other things are happening.....
I topped off my radiator and my overflow tank with new coolant, and replaced the radiator cap. For some reason, the coolant is overflowing into the tank, but not returning to the radiator. At times, the coolant will overflow out of the overflow tank, and onto the ground. However, the radiator is still not fool.....
I have verified that the overflow tank hose is NOT clogged, the male end of the radiator that the hose hooks up to on the radiator is also NOT clogged, and like I said, the radiator cap is brand new and operational.
Is there any reason why the coolant would not flow back into the radiator? I think I am missing something obvious here
Thanks in advance,
Alex
I topped off my radiator and my overflow tank with new coolant, and replaced the radiator cap. For some reason, the coolant is overflowing into the tank, but not returning to the radiator. At times, the coolant will overflow out of the overflow tank, and onto the ground. However, the radiator is still not fool.....
I have verified that the overflow tank hose is NOT clogged, the male end of the radiator that the hose hooks up to on the radiator is also NOT clogged, and like I said, the radiator cap is brand new and operational.
Is there any reason why the coolant would not flow back into the radiator? I think I am missing something obvious here

Thanks in advance,
Alex
Re: Crazy coolant
Yeah sounds like a bad head gasket, common problem in these cars. You need to test your coolant for hydrocarbons to be sure, the typical pressure test won't always show a problem in these cars since the hole in the HG is typically very small. You could also fill up the radiator and start the car with the cap off and check for bubbles.
The reason the coolant won't flow into the radiator is because there is too much air in the system from the leaking HG. This is also the reason why the overflow tank will overflow with coolant.
If you never overheated the car then chances are your head will be in good shape, however it will still be an expensive fix.
The reason the coolant won't flow into the radiator is because there is too much air in the system from the leaking HG. This is also the reason why the overflow tank will overflow with coolant.
If you never overheated the car then chances are your head will be in good shape, however it will still be an expensive fix.
Re: Crazy coolant
You wont have any other symptoms. My 03 had the classic old faithful coolant res. Compression test checked out even Exhaust gasses test passed.
What you will have is this lil guy
Re: Crazy coolant
OK....I am going to try and get a hydrocarbon tester to be sure. I will update when I et the results back. I just rolled 200k miles, this is NOT what I wanted to hear! LOL
FWIW.....if I do need a new HG, is there a recommended kit you all recommend? I am looking at rockauto and they range from $20-$90 and they go from just the HG to various other parts included.....
FWIW.....if I do need a new HG, is there a recommended kit you all recommend? I am looking at rockauto and they range from $20-$90 and they go from just the HG to various other parts included.....
Re: Crazy coolant
UHHHHHHHH......I ran the block tester today and everything checked out. I even kept the test going for 5 minutes. I am going to recheck tomorrow before I return the kit, but what else could be going on here?
Re: Crazy coolant
Hrm.... it's gotta be a head gasket. Run the car for a little bit.. park it, let it cool then do the hydrocarbon test. It shoulnd't be passing ... I've only seen 1 case on here where overflowing the overflow was not the result of a head gasket out of about 2000 posts.
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Re: Crazy coolant
200k? you went twice of mine lasted.
mine leak was very small, but not enough to cause overheating, but started loosing coolant from the tank. I did not do the hidrocarbon test, but it seems that many did not get any results but it was a HG anyway. Not sure of the reasons.
I bit the bullet anyway for the peace of mind - better to not to destroy the engine if that was the HG - which was - no more coolant loss.
mine leak was very small, but not enough to cause overheating, but started loosing coolant from the tank. I did not do the hidrocarbon test, but it seems that many did not get any results but it was a HG anyway. Not sure of the reasons.
I bit the bullet anyway for the peace of mind - better to not to destroy the engine if that was the HG - which was - no more coolant loss.
Re: Crazy coolant
^Yea your right laz it was the rad cap if I remember correctly. He said that he put a new rad cap on and when he started the car up he heard a huge suction noise, which was the coolant getting sucked out of the overflow into the engine back to its appropriate level.
Re: Crazy coolant
OK.....I am going to top off the radiator (leaving enough room to still run the test) and then complete the test a second time while the engine is at operating temp (last night I let it get to 1/4 way up thermo guage). I am also going to run a compression test on all four cylinders and report back.
Last edited by webster426; Nov 28, 2011 at 08:51 PM.
Re: Crazy coolant
OK, work and school are really crazy right now so I am going to have to hold off on the compression check.. However, I topped off the coolant this morning, and everything seemed to be holding just fine (I commute 52 miles one way to work). I got home and immediately retested the radiator using the block test. This time engine was definately at full operating temp, and I kept squeezing the tester for 5 minutes this time.
STILL no color change. I went back to the exhaust, and it did kinda smell moist. I grabbed a paper towel and held it infront of the exhaust pipe while the wife kept the engine around 1500RPM, and it did not get moist.
Am I just being a pain in the ars? Or does this all still point to the HG?
STILL no color change. I went back to the exhaust, and it did kinda smell moist. I grabbed a paper towel and held it infront of the exhaust pipe while the wife kept the engine around 1500RPM, and it did not get moist.
Am I just being a pain in the ars? Or does this all still point to the HG?
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Re: Crazy coolant
drain some coolant into a glass jar and look at it under the sun. if you see an oil sheen on the top surface, you have a leak. better test than anything sold in stores that may not pick up any hydrocarbons if the concentration is too low. the only sign of a headgasket i had was coolant being slowly burned and disappearing, and a short 1 minute single cylinder misfire when starting the engine cold. small leaks are really hard to test for, but its obvious they are real. compression check, coolant system pressure check, hydrocarbon test all came back clean even tho i had to add a cup of coolant each week. and white residue in the plugs.
Re: Crazy coolant
So if the HG is bad but it is barely burning off coolant.....there is no real need to take on this job correct? I mean, the car has over 200k miles now and this is not something that is going to really hurt anything. The heads will be fine as long as it does not over heat and that has not even come close to being an issue.
I will complete the compression check and drain some coolant to see what it looks like. I just cannot justify ripping apart the top part of that engine to fix a head gasket that is burning minimal levels of coolan (if any at all). I think we are all in agreance that it is really impossible to tell if it is bad until you open it up.
Engines have ran just fine even after the oil is all frothy, the exhaust is spewing steam, spark plugs are damaged, etc, etc. I am a LONG way from that happening if the leak is as minimal as it MIGHT be....
I will complete the compression check and drain some coolant to see what it looks like. I just cannot justify ripping apart the top part of that engine to fix a head gasket that is burning minimal levels of coolan (if any at all). I think we are all in agreance that it is really impossible to tell if it is bad until you open it up.
Engines have ran just fine even after the oil is all frothy, the exhaust is spewing steam, spark plugs are damaged, etc, etc. I am a LONG way from that happening if the leak is as minimal as it MIGHT be....
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Re: Crazy coolant
a slow leak will not cause major damage. just keep checking the coolant reservoir and add to max when it needs it. so long as the car does not misfire once the engine is warm (usually because the gasket seals when everything expands), you should be fine. the real trouble starts when oil and coolant start to mix (chocolate milk in the engine, or in the cooling system), when plugs get fouled from too much coolant burnoff, or if the coolant starts getting pushed out the overflow tank. or if the temp gauge starts to read above normal.you will get some air in the system, which may cause problems if you have air pockets around sensors (or the heater core which means not much heat in the cabin).
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