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?? -LOW COOLANT- ??

  • Thread starter Thread starter will_95gt
  • Start date Start date Mar 19, 2008

will_95gt

Member
Jul 27, 2004
298
1
16
Austin, TX
Mar 19, 2008
#1
  • Mar 19, 2008
  • #1
Ok, a few weeks ago I noticed my Low Coolant was illuminated. A few days later I got the oil changed and had them top off the coolant. Well, its only been two weeks and the low coolant light is back on

My first thought was a leaky head gasket; this is because, if I remember correctly, my car's previous owner had a similar problem. So, here's my question:

How can I tell where my coolant is leaking from? Also, if it is a leaky head gasket, is it easy to fix and why would it happen again within a few years? Cracked head?

Thanks guys,

-Will
 

Bosko5.0

Active Member
May 18, 2006
1,067
0
37
longwood, FL
Mar 19, 2008
#2
  • Mar 19, 2008
  • #2
Iam in the same situation mynes been on for 3-5 days last time it came on was a couple months ago.
 

94GTCoupe

10 Year Member
May 7, 2006
1,412
92
79
CA
Mar 19, 2008
#3
  • Mar 19, 2008
  • #3
check around your hose's for any corrosion,you can tell they are leaking if you see a white powdery substance.if it's a slow leak at the hose's,it can be easy to over look,and it won't leave a puddle under the car because it will burn off on the engine.
 

Chythar

Recently finished repairing my rear
20+ Year Stangneter
Aug 26, 2004
2,373
140
113
Foothill Ranch, CA
Mar 19, 2008
#4
  • Mar 19, 2008
  • #4
The low coolant sensor is in the overflow reservoir, and it can get corrosion on the sensors. Is the reservoir actually empty? If not, time to clean the sensor.

Low coolant can be caused by a leaky head gasket. But it can be caused by a leaking hose, a cracked radiator or simply a bad radiator cap. Check all the hose clamps, make sure they're all nice and tight. Make sure the petcock is closed nice & tight (drain valve on the bottom passenger side of the radiator). I'd also replace your radiator cap if you haven't in a while.

You also might want to get your coolant system pressure checked. If there's a leak, it won't hold enough pressure and it will leak. Our radiators tend to crack on the passenger's side, it's a flex point in the chassis. If your radiator is kinda old, that's another possibility.
 

will_95gt

Member
Jul 27, 2004
298
1
16
Austin, TX
Mar 21, 2008
#5
  • Mar 21, 2008
  • #5
Chythar said:
The low coolant sensor is in the overflow reservoir, and it can get corrosion on the sensors. Is the reservoir actually empty? If not, time to clean the sensor.

Low coolant can be caused by a leaky head gasket. But it can be caused by a leaking hose, a cracked radiator or simply a bad radiator cap. Check all the hose clamps, make sure they're all nice and tight. Make sure the petcock is closed nice & tight (drain valve on the bottom passenger side of the radiator). I'd also replace your radiator cap if you haven't in a while.

You also might want to get your coolant system pressure checked. If there's a leak, it won't hold enough pressure and it will leak. Our radiators tend to crack on the passenger's side, it's a flex point in the chassis. If your radiator is kinda old, that's another possibility.
Click to expand...

Ok, the radiator is about two years old, so are the upper and lower hoses. I started the car just now and the low coolant light didn't illuminate; I figured it might not because its pretty nice outside and the coolant light usually comes on only when its cold.

Anyways, I popped the hood and checked the upper and lower radiator hoses (the seem pretty snug). Then I noticed a drop--just one or two eyedropper drops--of green fluid on the top of the radiator just below the hose that goes from the radiator cap (silver cap on the right) to the reservoir (on the left). I pulled on the hose and it slid off the nipple by the silver cap with ease. There also seems to be some orange build up around that area that I'm thinking could be from coolant that has dried and sort of crusted.

So, my question is:

Is it common to have some coolant residing around this area or is this probably my leak? If it is, what do you think is causing that small hose to not make a good seal with the nipple? The hose looks to be in decent shape, should i buy a new one from O'reilly or something?

Thanks guys,

-Will

P.S. Chythar, great post! Thanks a lot.
 

will_95gt

Member
Jul 27, 2004
298
1
16
Austin, TX
Mar 21, 2008
#6
  • Mar 21, 2008
  • #6
Heres a pic' to illustrate my description:

http://s14.photobucket.com/albums/a311/will4fang/?action=view&current=radiatorhose.jpg
 

nisreo

New Member
Jul 22, 2006
178
0
0
Mar 21, 2008
#7
  • Mar 21, 2008
  • #7
Check under your oil cap for any milky residue. If there is some, but your oil comes out clean, thees a good chance when the headgaskets were done, they didnt apply sealer to the lower head bolts threads. From what Ive been told the lower bolts on the heads thread into a water jacket in the block. If you dont seal them before putting them back in, coolant will leak into your heads and burn up. Hence the milky oil cap and baffle and clean oil. I was told by an old time engine builder that Permatex #2 is what to use to seal those threads. It comes in a tube or bottle.
 

will_95gt

Member
Jul 27, 2004
298
1
16
Austin, TX
Mar 21, 2008
#8
  • Mar 21, 2008
  • #8
Interesting idea, nisreo. What do you think about the leak i was describing earlier?
 

95riosnake

Member
Dec 21, 2003
630
0
17
Pittsburgh, PA
Mar 23, 2008
#9
  • Mar 23, 2008
  • #9
Chythar said:
If not, time to clean the sensor.
Click to expand...

Did you try doing what Chythar said? I had the same problem a few years ago and that was the problem. The way it senses the coolant level is there are two electrodes on the sensor that goes in the overflow bottle, the coolant conducts electricity and "connects" the two electrodes. If they are not "connecting" to each other because of a buildup of gunk, the sensor will trigger the low coolant light.
 

Bosko5.0

Active Member
May 18, 2006
1,067
0
37
longwood, FL
Mar 23, 2008
#10
  • Mar 23, 2008
  • #10
put a hose clamp on that and it should stop the leak.

My leak seams to be the rad the bottom 3 fins were wet.
 

will_95gt

Member
Jul 27, 2004
298
1
16
Austin, TX
Mar 25, 2008
#11
  • Mar 25, 2008
  • #11
Ok, thanks for the responses guys. Rio, I'll have to deffinitely check out the sensors on that reservoir, are they easily accessible? The only thing is that its only reading low in the cold. If the sensor was dirty it seems like it would be reading low constantly.

Bosko, good thinking with the hose clamp... I suppose that would be a good temporary fix but I'm still curious as to why that leak began in the first place. Could the leak have been caused because of extra pressure for some reason in the coolant system?

Thanks a ton guys,

-Will
 

Chythar

Recently finished repairing my rear
20+ Year Stangneter
Aug 26, 2004
2,373
140
113
Foothill Ranch, CA
Mar 25, 2008
#12
  • Mar 25, 2008
  • #12
The leak is likely caused by an old rubber hose. They do wear out eventually. A hose clamp will definitely fix that leak. You'll have to make that fix and see if the problem goes away before you know for sure it was the cause of your low coolant.

In case you don't know, the coolant system is pressurized. When the coolant gets too hot (and the pressure in the system gets too high), the spring in the radiator cap compresses and coolant flows into the reservoir. When the coolant cools down, coolant flows back into the radiator through that leaky hose until the radiator cap spring closes the system off. So you're slowly losing coolant through that leak and letting air in the system.
 

will_95gt

Member
Jul 27, 2004
298
1
16
Austin, TX
Mar 25, 2008
#13
  • Mar 25, 2008
  • #13
Ah I see, very informative Chythar, thanks! I clamped the hose on tighter and it seems to be keeping dry now. I just have to top off the coolant--I'll let you guys know what happens next.
 
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