2003 possible coolant problem - Dexcool?
mazzov
01-22-2010, 07:21 AM
2003 Impala, 60k, oil change every 4K, no leaks.
Bought this car back in 3/2007 with 35K (yes a creampuff) before making the purchase I had done an inspection. When I checked the coolant level I saw a bunch of brown crud. The dealer (who has now closed shop) fixed the problem and I purchased the car. They said it was flushed.
Now almost 3 years later I am experiencing low engine temps (155 ish) while driving and noraml temp (185 ish) when idleing for long periods (10-15 mins). The car still makes heat however this morning after driving for about 25 mins (35F outside) I went to put my hand on the thermostat it wasn't hot. now i'm getting concerned.
I use to be one of those "car guys" but have been out of touch for a while now. I know the fans are working because I hear them turn on and off. I have not yet checked the fluids. I'm thinking that If they are low I will refill 50/50 distilled water and Dexcool (as hated as it is I am assuming that it is in the engine now). If that doesn't work I would assume I should have an acid flush. Should I be looking in the overflow tank? Typically I don't fill this because it's "overflow" but have seen mixed opinions on this.
Is there anything else I should be looking for?????
Bought this car back in 3/2007 with 35K (yes a creampuff) before making the purchase I had done an inspection. When I checked the coolant level I saw a bunch of brown crud. The dealer (who has now closed shop) fixed the problem and I purchased the car. They said it was flushed.
Now almost 3 years later I am experiencing low engine temps (155 ish) while driving and noraml temp (185 ish) when idleing for long periods (10-15 mins). The car still makes heat however this morning after driving for about 25 mins (35F outside) I went to put my hand on the thermostat it wasn't hot. now i'm getting concerned.
I use to be one of those "car guys" but have been out of touch for a while now. I know the fans are working because I hear them turn on and off. I have not yet checked the fluids. I'm thinking that If they are low I will refill 50/50 distilled water and Dexcool (as hated as it is I am assuming that it is in the engine now). If that doesn't work I would assume I should have an acid flush. Should I be looking in the overflow tank? Typically I don't fill this because it's "overflow" but have seen mixed opinions on this.
Is there anything else I should be looking for?????
magnetman
01-24-2010, 06:40 AM
I would look in and fill the overflow. They have a "full cold" line in there for a reason. Is there any coolant in the overflow now?
If not you may be losing coolant somewhere in the engine. What engine is in the vehicle? Are there signs of coolant in the oil (milky colored and/or foamy)?
Dex has been know to rot out the Upper and Lower intake manifold gaskets ( Dex cool info site (http://www.dex-cool.net/) ) on the 3800 engines and other engines causing leaking into cylinders and/or oil pan (I've got a Bonneville with a 3800 now with the problem and I'm getting ready to do the UIM and LIM gaskets on it). A lot of people flush and change from Dex to Preston long life mix with any color coolant because of Dex.
Did you actually touch the thermostat housing or the upper radiator hose? Sounds like the thermostat may not be opening either but, with your description of 155 degrees running and 185 degrees while sitting, I'd say it sounds like it may be stuck open so that may be no help. Best way to tell if the thermostat is stuck open is to start the car and keep your hand on the upper hose. If it heats up slowly, over time, the thermostat is stuck open. If it stays cold until the engine is heated up to the proper temp and then it gets hot suddenly then the thermostat is working fine.
Check coolant levels first. You should have coolant in the overflow up to the "Full Cold" line when the engine is cold. If there is none, fill the coolant and then check the hose after driving some. Then keep an eye on the coolant level for awhile *unless there are signs of a coolant leak into the oil*. If this is the case don't drive it any longer.
Think I've babbled on long enough.
If not you may be losing coolant somewhere in the engine. What engine is in the vehicle? Are there signs of coolant in the oil (milky colored and/or foamy)?
Dex has been know to rot out the Upper and Lower intake manifold gaskets ( Dex cool info site (http://www.dex-cool.net/) ) on the 3800 engines and other engines causing leaking into cylinders and/or oil pan (I've got a Bonneville with a 3800 now with the problem and I'm getting ready to do the UIM and LIM gaskets on it). A lot of people flush and change from Dex to Preston long life mix with any color coolant because of Dex.
Did you actually touch the thermostat housing or the upper radiator hose? Sounds like the thermostat may not be opening either but, with your description of 155 degrees running and 185 degrees while sitting, I'd say it sounds like it may be stuck open so that may be no help. Best way to tell if the thermostat is stuck open is to start the car and keep your hand on the upper hose. If it heats up slowly, over time, the thermostat is stuck open. If it stays cold until the engine is heated up to the proper temp and then it gets hot suddenly then the thermostat is working fine.
Check coolant levels first. You should have coolant in the overflow up to the "Full Cold" line when the engine is cold. If there is none, fill the coolant and then check the hose after driving some. Then keep an eye on the coolant level for awhile *unless there are signs of a coolant leak into the oil*. If this is the case don't drive it any longer.
Think I've babbled on long enough.
j cAT
01-24-2010, 05:24 PM
2003 Impala, 60k, oil change every 4K, no leaks.
Bought this car back in 3/2007 with 35K (yes a creampuff) before making the purchase I had done an inspection. When I checked the coolant level I saw a bunch of brown crud. The dealer (who has now closed shop) fixed the problem and I purchased the car. They said it was flushed.
Now almost 3 years later I am experiencing low engine temps (155 ish) while driving and noraml temp (185 ish) when idleing for long periods (10-15 mins). The car still makes heat however this morning after driving for about 25 mins (35F outside) I went to put my hand on the thermostat it wasn't hot. now i'm getting concerned.
I use to be one of those "car guys" but have been out of touch for a while now. I know the fans are working because I hear them turn on and off. I have not yet checked the fluids. I'm thinking that If they are low I will refill 50/50 distilled water and Dexcool (as hated as it is I am assuming that it is in the engine now). If that doesn't work I would assume I should have an acid flush. Should I be looking in the overflow tank? Typically I don't fill this because it's "overflow" but have seen mixed opinions on this.
Is there anything else I should be looking for?????
I would flush out the coolant system use acid flush rise with baking soda solution...drain entire coolant system including the engine, ..do this with the thermostat removed and don't forget the heater core needs to be blown out...when draining the coolant system measure the amount you drain out ..this should be about 3.75 gallons....this means about 2.5 gallons of dexcool and the rest distilled water this is 65% dexcool....
dexcool has been used by me since 1996 with these ratios and these gaskets fail because the metal corrodes not just this engine but many others....this dexcool requires replacement at every 3-4 years mileage is not a factor...never ever run with low coolant with dexcool this is how the system gets gooped up with the brown/black goo...
I was puzzled at how many owners had issues with dexcool ...
these forums have shown me that many do not properly maintain the coolant systems especially those that live in the warm climates where antifreeze to these people is an option...
Bought this car back in 3/2007 with 35K (yes a creampuff) before making the purchase I had done an inspection. When I checked the coolant level I saw a bunch of brown crud. The dealer (who has now closed shop) fixed the problem and I purchased the car. They said it was flushed.
Now almost 3 years later I am experiencing low engine temps (155 ish) while driving and noraml temp (185 ish) when idleing for long periods (10-15 mins). The car still makes heat however this morning after driving for about 25 mins (35F outside) I went to put my hand on the thermostat it wasn't hot. now i'm getting concerned.
I use to be one of those "car guys" but have been out of touch for a while now. I know the fans are working because I hear them turn on and off. I have not yet checked the fluids. I'm thinking that If they are low I will refill 50/50 distilled water and Dexcool (as hated as it is I am assuming that it is in the engine now). If that doesn't work I would assume I should have an acid flush. Should I be looking in the overflow tank? Typically I don't fill this because it's "overflow" but have seen mixed opinions on this.
Is there anything else I should be looking for?????
I would flush out the coolant system use acid flush rise with baking soda solution...drain entire coolant system including the engine, ..do this with the thermostat removed and don't forget the heater core needs to be blown out...when draining the coolant system measure the amount you drain out ..this should be about 3.75 gallons....this means about 2.5 gallons of dexcool and the rest distilled water this is 65% dexcool....
dexcool has been used by me since 1996 with these ratios and these gaskets fail because the metal corrodes not just this engine but many others....this dexcool requires replacement at every 3-4 years mileage is not a factor...never ever run with low coolant with dexcool this is how the system gets gooped up with the brown/black goo...
I was puzzled at how many owners had issues with dexcool ...
these forums have shown me that many do not properly maintain the coolant systems especially those that live in the warm climates where antifreeze to these people is an option...
mazzov
01-27-2010, 09:01 AM
Thx guys.
As of today I have had the engine flushed and replaced fluid with new "green" fluid based on recommendations from my mechanic (I would have done it myself but I am a bit more "eco" now than I was in the past). He did point out however that my radiator cap may be bad. When he squeezed on the top tube air was going into the overflow. I was thinking that this could also be a reason why the car isn't coming up to temp. So I went out to Carquest and picked up a new cap. When I put it on I got the same exact result with air going into the overflow. I am going to go to a Napa auto parts today to see if the cap that they sell (hopefully a different manufacturer) will work.
Am I missing anything else besides the possibility of the thermostat?
thx.
As of today I have had the engine flushed and replaced fluid with new "green" fluid based on recommendations from my mechanic (I would have done it myself but I am a bit more "eco" now than I was in the past). He did point out however that my radiator cap may be bad. When he squeezed on the top tube air was going into the overflow. I was thinking that this could also be a reason why the car isn't coming up to temp. So I went out to Carquest and picked up a new cap. When I put it on I got the same exact result with air going into the overflow. I am going to go to a Napa auto parts today to see if the cap that they sell (hopefully a different manufacturer) will work.
Am I missing anything else besides the possibility of the thermostat?
thx.
j cAT
01-27-2010, 10:47 AM
Thx guys.
As of today I have had the engine flushed and replaced fluid with new "green" fluid based on recommendations from my mechanic (I would have done it myself but I am a bit more "eco" now than I was in the past). He did point out however that my radiator cap may be bad. When he squeezed on the top tube air was going into the overflow. I was thinking that this could also be a reason why the car isn't coming up to temp. So I went out to Carquest and picked up a new cap. When I put it on I got the same exact result with air going into the overflow. I am going to go to a Napa auto parts today to see if the cap that they sell (hopefully a different manufacturer) will work.
Am I missing anything else besides the possibility of the thermostat?
thx.
if the complete coolant system was drained, including the engine,heater core, not just radiator , then flushed with the acid , you should have no problems with the green long life coolant...
distilled water is also needed with any coolant..
As of today I have had the engine flushed and replaced fluid with new "green" fluid based on recommendations from my mechanic (I would have done it myself but I am a bit more "eco" now than I was in the past). He did point out however that my radiator cap may be bad. When he squeezed on the top tube air was going into the overflow. I was thinking that this could also be a reason why the car isn't coming up to temp. So I went out to Carquest and picked up a new cap. When I put it on I got the same exact result with air going into the overflow. I am going to go to a Napa auto parts today to see if the cap that they sell (hopefully a different manufacturer) will work.
Am I missing anything else besides the possibility of the thermostat?
thx.
if the complete coolant system was drained, including the engine,heater core, not just radiator , then flushed with the acid , you should have no problems with the green long life coolant...
distilled water is also needed with any coolant..
mazzov
01-27-2010, 11:42 AM
I'm confident that the guy did the job correctly (have used him in the past) and probably should have had him replace the radiator cap also.
I am not sure exactly what "stages" a radiator cap goes thru. Please correct me if I'm wrong.
Engine cold = cap should be in closed position not allowing air or fluids to enter radiator.
Engine hot = cap should be in closed position not allowing air or fluids to enter radiator.
Engine overheating = cap opens allowing fluids into the overflow tank.
Engine ??? = allows fluids from overflow tank back into radiator.
I am trying to determine if the radiator cap is good or not. If I squeeze the top hose with the engine cold I get fluids/air into the overflow. Is this normal? I'm going to try when the engine is hot (after a 30 drive).
When buying a new radiator cap is it in the "fully expanded" position?
Car does make heat.
thx
I am not sure exactly what "stages" a radiator cap goes thru. Please correct me if I'm wrong.
Engine cold = cap should be in closed position not allowing air or fluids to enter radiator.
Engine hot = cap should be in closed position not allowing air or fluids to enter radiator.
Engine overheating = cap opens allowing fluids into the overflow tank.
Engine ??? = allows fluids from overflow tank back into radiator.
I am trying to determine if the radiator cap is good or not. If I squeeze the top hose with the engine cold I get fluids/air into the overflow. Is this normal? I'm going to try when the engine is hot (after a 30 drive).
When buying a new radiator cap is it in the "fully expanded" position?
Car does make heat.
thx
j cAT
01-27-2010, 04:08 PM
my description of what should have been done is from many decades of servicing coolant systems ..these technic's are for me correct ..the technician you used my find this all too time consuming and because he is in need of cash not reliability who knows what he really did...
ask him what he did...then compare with my recommendations...
the coolant cap keeps the coolant at 15psi when the coolant is at operating temp..this prevents coolant boiling...with no pressure at sea level coolant boils at 212f....in dever co. I think it boils at 190deg F...If it boils your water pump cannot pump air so the engine overheats...
with 15psi I think it boils around 250deg f....
as the coolant cools , engine off ,, the cap allows coolant to enter the radiator...as the pressure drops it will siphon coolant from the non pressurized reservoir...this is where hot /cold marks come into play..if its running correctly when hot at the hot line when cold at the cold line ..
squeezing the coolant hose and observing the coolant flow is not how to correctly check this ,,you will need a pressure test to see that the cap/coolant system is at the correct pressures when hot to ensure that the cap is good the coolant system has no leaks..
ask him what he did...then compare with my recommendations...
the coolant cap keeps the coolant at 15psi when the coolant is at operating temp..this prevents coolant boiling...with no pressure at sea level coolant boils at 212f....in dever co. I think it boils at 190deg F...If it boils your water pump cannot pump air so the engine overheats...
with 15psi I think it boils around 250deg f....
as the coolant cools , engine off ,, the cap allows coolant to enter the radiator...as the pressure drops it will siphon coolant from the non pressurized reservoir...this is where hot /cold marks come into play..if its running correctly when hot at the hot line when cold at the cold line ..
squeezing the coolant hose and observing the coolant flow is not how to correctly check this ,,you will need a pressure test to see that the cap/coolant system is at the correct pressures when hot to ensure that the cap is good the coolant system has no leaks..
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