ndu Posted February 28, 2005 Share Posted February 28, 2005 I kept my coolant level in the over flow tank between "LOW" and "HIGH" (actually close to LOW mark). After some mixed mode driving including some highway, the coolant level in the overflow tank will allmost full to nearly overflow. I think there may be a problem here. After I shutoff the engine, I can see in motion the coolant very quicky being sucked back to the radiator. I do not know if this is normal to Legacy 93....because this is still winter in Toronto. My car did not show any overheating (temperature guage allways points to the middle) I am concerned that so much coolant has been pushed out of the engine and radiator....Is this possibly due to a bad head gasket? Doesn't look like it because I am not comsuming coolant and I do not smell any coolant. Possibly a bad radiator cap? It looks and feels normal. Can somebody advise? I know there is the possibiity of gas pockets in the system so when I fill the system, I was careful and opened the air bleeder.... The Engine runs normal otherwise. Thanks Quote Link to comment Share on other sites More sharing options...
blitz Posted March 1, 2005 Share Posted March 1, 2005 It's normal for the level to increase some, but not by quite that much. What's the history on the vehicle? Did it just begin doing this? Quote Link to comment Share on other sites More sharing options...
ndu Posted March 1, 2005 Author Share Posted March 1, 2005 I got the car recently so I do not know when it started......I have just chnaged the timing belt, water pump, changed the entire coolant...... Quote Link to comment Share on other sites More sharing options...
frag Posted March 1, 2005 Share Posted March 1, 2005 I got the car recently so I do not know when it started......I have just chnaged the timing belt, water pump, changed the entire coolant...... Since the coolant is being sucked back in, it does'nt sound like there's a leak in the coolant system (head gasket failure). I would vote for an air pocket. Heated air expands a lot more than fluid, so it could account for the pressure that's pushing the coolant into the overflow reservoir. I might also be as simple as a faulty rad cap. I would begin by replacing that cause it's cheap. Some people here have explained a method of burping the cooling system. If you make a search along those lines, you will find info to that effect. Just an amateur's opinion. Good luck! Quote Link to comment Share on other sites More sharing options...
mtsmiths Posted March 1, 2005 Share Posted March 1, 2005 Another amateur chimes in with an air bubble diagnosis. Burp it, or you'll be doing a head gasket next ... there's a thread to that effect somewhere too. Quote Link to comment Share on other sites More sharing options...
Downbound Posted March 1, 2005 Share Posted March 1, 2005 had a similar problem with my 99 forester..After a long drive the overflow would be full and have tiny bubblesin it, turned out to be the head gasket..although I did try a new rad cap and burping the system first just because it makes sense to start with the easiest and cheapest fix and work from there... good luck.. I kept my coolant level in the over flow tank between "LOW" and "HIGH" (actually close to LOW mark). After some mixed mode driving including some highway, the coolant level in the overflow tank will allmost full to nearly overflow. I think there may be a problem here. After I shutoff the engine, I can see in motion the coolant very quicky being sucked back to the radiator. I do not know if this is normal to Legacy 93....because this is still winter in Toronto. My car did not show any overheating (temperature guage allways points to the middle) I am concerned that so much coolant has been pushed out of the engine and radiator....Is this possibly due to a bad head gasket? Doesn't look like it because I am not comsuming coolant and I do not smell any coolant. Possibly a bad radiator cap? It looks and feels normal. Can somebody advise? I know there is the possibiity of gas pockets in the system so when I fill the system, I was careful and opened the air bleeder.... The Engine runs normal otherwise. Thanks Quote Link to comment Share on other sites More sharing options...
Setright Posted March 1, 2005 Share Posted March 1, 2005 Since you recently replaced the coolant, I would reckon that it's just trapped air. Search the site and learn how to purge the air correctly. If you wanna read more of my stuff search "Coolant replacment"... Fitting a new rad cap is a good idea, too. Quote Link to comment Share on other sites More sharing options...
ndu Posted March 1, 2005 Author Share Posted March 1, 2005 I drove a while today and checked the overflow tank and I do not see any bubles.....I think I will try the rad cap replacement first. Any ideas how much it will cost? any after market ones? Other observation is that my after driving for a while, my cooling fan will be always on ---- after I stop the car and kept the engine idle, the fan will keep on going -- I waited a few minutes and the fan will not stop. I think my car is experiencing a very mild overheating because the coolant at the top of the engine (where the temperature sensor located) may have been pushed out of the system so the sensor sees a slight higher temperature than the actual coolant temperature (because not enough coolant near by to take away the heat) therefore it will trigger the fan--but the temperature gauge will still roughly in the middle position--a plausible theory? Thanks for all replied. Quote Link to comment Share on other sites More sharing options...
Setright Posted March 2, 2005 Share Posted March 2, 2005 Plausible. Then again, sometimes those fans just seem to have a mind of their own! Quote Link to comment Share on other sites More sharing options...
frag Posted March 2, 2005 Share Posted March 2, 2005 I drove a while today and checked the overflow tank and I do not see any bubles.....I think I will try the rad cap replacement first. Any ideas how much it will cost? any after market ones? Other observation is that my after driving for a while, my cooling fan will be always on ---- after I stop the car and kept the engine idle, the fan will keep on going -- I waited a few minutes and the fan will not stop. I think my car is experiencing a very mild overheating because the coolant at the top of the engine (where the temperature sensor located) may have been pushed out of the system so the sensor sees a slight higher temperature than the actual coolant temperature (because not enough coolant near by to take away the heat) therefore it will trigger the fan--but the temperature gauge will still roughly in the middle position--a plausible theory? Thanks for all replied. My scan tool gives me the exact coolant temp values and this shows that the gauge (my recollection is not exact) gets in it's «normal» position (at the bottow of the thermomete icon) at around 165°F and stays there until the temp rises to around 195°F or until the fans kicks in. So it's possible for your coolant temp sensor to sense a slight overeated situation without the gauge needle moving up. Quote Link to comment Share on other sites More sharing options...
ndu Posted March 12, 2005 Author Share Posted March 12, 2005 My theory is correct! I went to the Subaru dealer and asked them to test my rad cap to see if it can hold pressure. They were nice enough to do it for free. Sure enough, the cap was not working properly. So I got a new one from Canadian Tire for $10 and the cooling system is working normal now. Also my fan problem is also fixed---previously it was on all the time when engine is at normalo temperature. It feels good if your theory turns out to be true. Quote Link to comment Share on other sites More sharing options...
MDW25gt Posted March 12, 2005 Share Posted March 12, 2005 Sounds like early stages of head gasket failure. There is a lot hight pressure in the combustion chamber than the raditor. That was my experience. Repeated high level in the overflow, return to notmale level, then finaly when the head gasket leak got bad enough the coolent would come out of the overflow tank and result in a low coolent condition. I kept my coolant level in the over flow tank between "LOW" and "HIGH" (actually close to LOW mark). After some mixed mode driving including some highway, the coolant level in the overflow tank will allmost full to nearly overflow. I think there may be a problem here. After I shutoff the engine, I can see in motion the coolant very quicky being sucked back to the radiator. I do not know if this is normal to Legacy 93....because this is still winter in Toronto. My car did not show any overheating (temperature guage allways points to the middle) I am concerned that so much coolant has been pushed out of the engine and radiator....Is this possibly due to a bad head gasket? Doesn't look like it because I am not comsuming coolant and I do not smell any coolant. Possibly a bad radiator cap? It looks and feels normal. Can somebody advise? I know there is the possibiity of gas pockets in the system so when I fill the system, I was careful and opened the air bleeder.... The Engine runs normal otherwise. Thanks Quote Link to comment Share on other sites More sharing options...
later, Peter Posted March 12, 2005 Share Posted March 12, 2005 My theory is correct! I went to the Subaru dealer and asked them to test my rad cap to see if it can hold pressure. They were nice enough to do it for free. Sure enough, the cap was not working properly. So I got a new one from Canadian Tire for $10 and the cooling system is working normal now. Also my fan problem is also fixed---previously it was on all the time when engine is at normalo temperature. It feels good if your theory turns out to be true. Best bet is to burp the baby too.... It appears that many HG problems come from trapping air pockets in Subarus poorly designed cooling system... why let it get that far? this is a cost effective (free) preventative manuever.. check the archives. later, Peter Quote Link to comment Share on other sites More sharing options...
frag Posted March 12, 2005 Share Posted March 12, 2005 My theory is correct! I went to the Subaru dealer and asked them to test my rad cap to see if it can hold pressure. They were nice enough to do it for free. Sure enough, the cap was not working properly. So I got a new one from Canadian Tire for $10 and the cooling system is working normal now. Also my fan problem is also fixed---previously it was on all the time when engine is at normalo temperature. It feels good if your theory turns out to be true. Can I share part of the glory? Check post number #4. Quote Link to comment Share on other sites More sharing options...
neil mc Posted March 12, 2005 Share Posted March 12, 2005 Hi, Theres nothing worse than not knowing what the problem is. I had to replace a radiator and coolant about 6mts ago. For a long long long time after i had air in the system somewhere near the heater core. Nothing would shift it. I had my mechanic re do coolant change but problem still existed. I then began trying to sort it myself. I tried putting front up on a slope of 40 deg and following Setright's excellent instructions but this didnt help.(although its helped a neighbour with his car) Eventually by squeezing the lower hose forcing air to top hose and then slightly opening radiator cap while still holding the lower hose i got a lot of air out. I then replaced cap and could hear coolant being sucked from overflow, then let go of lower hose. I then repeated the process but this time squeezed top radiator hose. The whole process should be done while coolant in warm but not too hot (i suggest running engine for 5-10 min). I repeated the process on 2/3 more days over a two week period. Now I have all the air out, well I hope so anyway - can't hear any more swishing of water when I rev which was very evident before. Look at some of my previous threads for my full story. Really hope this helps I know how you feel regarding wondering if HG is gone. Neil Quote Link to comment Share on other sites More sharing options...
frag Posted March 12, 2005 Share Posted March 12, 2005 Hi, Theres nothing worse than not knowing what the problem is. I had to replace a radiator and coolant about 6mts ago. For a long long long time after i had air in the system somewhere near the heater core. Nothing would shift it. I had my mechanic re do coolant change but problem still existed. I then began trying to sort it myself. I tried putting front up on a slope of 40 deg and following Setright's excellent instructions but this didnt help.(although its helped a neighbour with his car) Eventually by squeezing the lower hose forcing air to top hose and then slightly opening radiator cap while still holding the lower hose i got a lot of air out. I then replaced cap and could hear coolant being sucked from overflow, then let go of lower hose. I then repeated the process but this time squeezed top radiator hose. The whole process should be done while coolant in warm but not too hot (i suggest running engine for 5-10 min). I repeated the process on 2/3 more days over a two week period. Now I have all the air out, well I hope so anyway - can't hear any more swishing of water when I rev which was very evident before. Look at some of my previous threads for my full story. Really hope this helps I know how you feel regarding wondering if HG is gone. Neil For what it's worth. A couple of years ago I installed a Prestone T fitting (for flushing the coolant system) with screw on cap in one of the coolant hoses connecting to the heater core (dont remember if inlet or outlet, but it's written in the Prestone fitting package). Opening this cap when refilling the coolant system seems to help a lot to get all the air out. At one point the rad was full and nothing could make the level go down but I could still get more than a quart of coolant in thru this fitting. Never had any problem with residual air. In case someone would want to try that as a last resort... or first. Quote Link to comment Share on other sites More sharing options...
ndu Posted March 12, 2005 Author Share Posted March 12, 2005 ya, Frag, 50% is yours! Quote Link to comment Share on other sites More sharing options...
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