i am having an overheating problem which has caused my car to sit in my driveway......... mods are listed in sig, car normally runs very cool, by the "a" or "l" on the temp gauge. recently it has decided to overheat on me! it happened one time about 1 1/2 months ago, the temp went all the way up to about 240-250*. i looked for leaks in the cooling system ( hoses radiator etc.) and found none. the antifreeze level was fine. the same thing happened twice this week, and the antifreeze was really low. the car is parked in a garage, and there has been no sign of coolant on the floor. i am wondering if my coolant is evaporating on me for some reason? or maybe the water pump is fainling to turn and the coolant is boiling off? any help would be appreciated!
cooling system question......
- Thread starter KCoppola
- Start date
sunil6784
Member
Is the thermostat opening? Could be a stuck thermostat...
Does it happen all the time? Highway driving ? Idle ?
Also, I'll be the first to say it, because I'm pretty sure everyone else will. I wouldn't trust the stock gauges as far as I can throw them...well throw the gauge cluster.
Does it happen all the time? Highway driving ? Idle ?
Also, I'll be the first to say it, because I'm pretty sure everyone else will. I wouldn't trust the stock gauges as far as I can throw them...well throw the gauge cluster.
bill302
Active Member
timewarped1972
Member
if you don't see any evidence as suggested above of it being a head gasket, try flushing it.
take the top hose off, have a garden hose ready, start it, and see if when it warms up coolant is flowing out of the top hose like it should. being you have coolant in it maybe drain it and refill with water so your not wasting coolant all over the place....
this should tell you if your t-stat is opening and your pump circulating.
another less invasive option would be to start it, take the radiator cap off ( when it's cold) and as it heats up shine a flash light in the radiator to see if coolant is moving once it gets to a temp where the t-stat should open.....
take the top hose off, have a garden hose ready, start it, and see if when it warms up coolant is flowing out of the top hose like it should. being you have coolant in it maybe drain it and refill with water so your not wasting coolant all over the place....
this should tell you if your t-stat is opening and your pump circulating.
another less invasive option would be to start it, take the radiator cap off ( when it's cold) and as it heats up shine a flash light in the radiator to see if coolant is moving once it gets to a temp where the t-stat should open.....
What Tstat are you using?
The Griffin and e- fan should be able to handle that combo fairly easily.
Had you done any changes just before the problems began?
It is very possible to get a coolant leak that does not leak until the motor is hot. I had a leak from one of the heater core hoses that was very small. The only reason I found it was that I looked under the hood while the motor was hot and running, and witnessed a single drop of coolant drop on the header.
As asked above when does the overheat occur, this will help alot in troubleshooting.
jason
The Griffin and e- fan should be able to handle that combo fairly easily.
Had you done any changes just before the problems began?
It is very possible to get a coolant leak that does not leak until the motor is hot. I had a leak from one of the heater core hoses that was very small. The only reason I found it was that I looked under the hood while the motor was hot and running, and witnessed a single drop of coolant drop on the header.
As asked above when does the overheat occur, this will help alot in troubleshooting.
jason
thanks for the responses folks! i have tried much of this stuff already, the radiator is pretty new and an expensive piece, fortunately it looks like new on the inside. the thermostat is opening, i checked that too...... i cant find a leak anywhere, and i have tried believe me! negative on the white foam, but that was an interesting comment...what would white foam mean? an interesting point that is leading me to believe that the passenger side head gasket may be blown is that when it gets close to the point of overheating, the radiator on the passenger side of the car is too hot to touch, while at the same time, the driver's side of the radiator is cool to the touch.....so in a couple days when i am off, i guess i will explore that possibility...between burnt up hot wires to the alternator last week, and now this, i am starting to lose my patience and want to take it to someone else and tell them to fix it!!! i appreciate all the help everyone 
btw.... i have made no mods to the car that culd have caused this, unless plugs and wires count! it has a 140* thermostat...this car usually runs amazingly cool
btw.... i have made no mods to the car that culd have caused this, unless plugs and wires count! it has a 140* thermostat...this car usually runs amazingly cool
sunil6784
Member
White foam would point to a head gasket.
140 deg thermostat !! Get a 180 in that ! Stock is 192, thats 50 degrees colder that the engine is running...
140 deg thermostat !! Get a 180 in that ! Stock is 192, thats 50 degrees colder that the engine is running...
$uperstang
New Member
Here are some general thoughts of mine on cooling systems.
No doubt that low of a t-stat is causing some issues. There is a fairly common theory that removing the stat (which is basically what you have with a 140 stat) can cause very high coolant temps by not allowing the coolant enough time in the rad to allow for adequate cooling. Basically the coolant flies through the radiator and back to the motor before it has a chance to cool down.
I would first install a stock stat, although most will say a 180F.
The reason one side of the radiator is hotter than the other is that the coolant enters on one side (hot) and exits on the other (cold). Nothing to worry about there.
Unless you have some odd-ball combo the 160F (or lower) stat will do more harm than good. The lower cylinder temps will increase bore wear, engine oil will not get up to temp, and power and economy will most likely suffer due to poor combustion. Depending on the source, ideal coolant temps will be anywhere from 195F to 220F.
Most people feel that the 180F stat is a good compromise. I ran one for several years in a stockish 302, with no noticeable problems.
Hope this helps by bringing up some of the factors to consider when changing the coolant T-stat.
The literatures I have read (mostly SAE published papers) tend to indicate that the engine is most efficient around 200F coolant temps. The coldest coolant temp I have seen for any test (whether analyzing power/emissions/economy) has been 190F, anything lower seems to be considered cold start. The highest temp I have seen in a test is 240F. At 350F the glycol coolant degrades to form corrosive acids. The 350F limit is a local temp, for example in the head, between the valves. I am unsure how to correlate the 350F max allowable temp to ECT sensor readings.
Coolant/water mixtures should be at 50/50 whether using ethylene glycol or propylene glycol. I have seen SAE published papers that tested different ratios between 30/70 and 70/30. The best all around performance tends to be at 50/50.
Water is a better cooling fluid than the glycols, but does not provide the corrosion protection.
Another danger with straight water, which is hardly ever mentioned, is Cavitation. Cavitation damage occurs when the coolant experiences brief low pressure, followed by a return to high pressure. This situation is primarily found in water pumps, but is also common on the coolant side of cylinder walls of diesel engines.
As the pressure drops, the coolant forms small vapor pockets. When the system pressure increases, the vapor pockets collapse. The collapse releases a large amount of energy, which can damage the surface of metal materials. Think of a bubble popping, but with much greater force. By raising the vaporization temp of the coolant, glycol additives will help prevent cavitation. Using a proper radiator cap pressure will do this as well, as increasing the pressure in the entire system will provide protection against local low pressure zones.
No doubt that low of a t-stat is causing some issues. There is a fairly common theory that removing the stat (which is basically what you have with a 140 stat) can cause very high coolant temps by not allowing the coolant enough time in the rad to allow for adequate cooling. Basically the coolant flies through the radiator and back to the motor before it has a chance to cool down.
I would first install a stock stat, although most will say a 180F.
The reason one side of the radiator is hotter than the other is that the coolant enters on one side (hot) and exits on the other (cold). Nothing to worry about there.
Unless you have some odd-ball combo the 160F (or lower) stat will do more harm than good. The lower cylinder temps will increase bore wear, engine oil will not get up to temp, and power and economy will most likely suffer due to poor combustion. Depending on the source, ideal coolant temps will be anywhere from 195F to 220F.
Most people feel that the 180F stat is a good compromise. I ran one for several years in a stockish 302, with no noticeable problems.
Hope this helps by bringing up some of the factors to consider when changing the coolant T-stat.
The literatures I have read (mostly SAE published papers) tend to indicate that the engine is most efficient around 200F coolant temps. The coldest coolant temp I have seen for any test (whether analyzing power/emissions/economy) has been 190F, anything lower seems to be considered cold start. The highest temp I have seen in a test is 240F. At 350F the glycol coolant degrades to form corrosive acids. The 350F limit is a local temp, for example in the head, between the valves. I am unsure how to correlate the 350F max allowable temp to ECT sensor readings.
Coolant/water mixtures should be at 50/50 whether using ethylene glycol or propylene glycol. I have seen SAE published papers that tested different ratios between 30/70 and 70/30. The best all around performance tends to be at 50/50.
Water is a better cooling fluid than the glycols, but does not provide the corrosion protection.
Another danger with straight water, which is hardly ever mentioned, is Cavitation. Cavitation damage occurs when the coolant experiences brief low pressure, followed by a return to high pressure. This situation is primarily found in water pumps, but is also common on the coolant side of cylinder walls of diesel engines.
As the pressure drops, the coolant forms small vapor pockets. When the system pressure increases, the vapor pockets collapse. The collapse releases a large amount of energy, which can damage the surface of metal materials. Think of a bubble popping, but with much greater force. By raising the vaporization temp of the coolant, glycol additives will help prevent cavitation. Using a proper radiator cap pressure will do this as well, as increasing the pressure in the entire system will provide protection against local low pressure zones.
DMAN302
My mom says thanks for the pearl necklace.
White foam is not the only indication of headgasket...the initial overheating could have been caused by several factors, and the result of the high temps the aluminum heads may have been affected by the heat and then caused a headgasket failure. I would drain the oil and check the color...if the color is milky, I'd be looking to pull the heads. The coolant leaving the system can be either leaked or burnt...it doesn't evaporate so I'm inclined to look at the HG being an issue. I would not hesitate for one second to have the heads inspected BEFORE reinstalling them to check the mating surface for any warpage...they may need to be milled. Good luck and hope all turns out OK.
Michael Yount
Mustang Master
"Also what is the condition of the coors in the radiator..."
Now there's a problem right there -- you should DRINK the Coors; only run Bud or Miller in the radiator.
Now there's a problem right there -- you should DRINK the Coors; only run Bud or Miller in the radiator.
Zero_chance
Founding Member
If you have access to a laser temperature gauge, point it at the hoses and see what the temp is actually at. Check the input and output hoses at the heater core and the upper and lower of the radiator.
Oh my god, I spelled a word wrong and got caught by the grammar police. PLEASE forgive me everyone for such a terrible mistake in trying to help out a fellow stanger!!! (you know, when I was reading my post somethin' just didin't look right but I just couldn't put my finger on it!!)Michael Yount said:"Also what is the condition of the coors in the radiator..."
Now there's a problem right there -- you should DRINK the Coors; only run Bud or Miller in the radiator.
:SNSign:
Michael Yount said:"Also what is the condition of the coors in the radiator..."
Now there's a problem right there -- you should DRINK the Coors; only run Bud or Miller in the radiator.
You couln't pay me to drink any of those! May as well just drink O'Douls.
Run the car up to operating temperature with the radiator cap off and add coolant as necessary. It's not totally uncommon for air to be trapped somewhere in the system, and eventually making its way to a point where it impedes the flow, and eventually it gets hot enough to expand/boil and cause a momentary return of flow, and a spike in temp on the gauge. Once it flows again, it cools back down, and your gauge shows normal again, since it may actually be reading air temperature inside the intake. It might also help to jack the front end of the car up some while doing this, so the radiator is the high point in the cooling system, since air tries to find that point. Once you're sure there's no air, one of the easier ways to *possibly* detect a bad headgasket is to watch for bubbles in the radiator. Hope this helps!
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