How Many Times Can a Car Be Overheated?

[The Critic]

My mom and I share a '96 Saturn SL2. Current mileage is about 136k.

Recently, the car was overheated for a third time. A radiator hose had a slight leak, which resulted in a cloud of steam from the hood during a morning highway commute. My mom did not know where the steam was coming from, so she finished off her highway commute despite the massive amount of steam from the underhood area. The highway commute probably lasted for another 20 miles or so at low-speeds. Later that day, my dad fixed the hose, refilled the cooling system and claims the car works fine.

There has also been two previous incidents. One incident was at the 60k mark, where the serpentine belt tensioner failed and the car was driven for about 10 miles without a fully functional water pump. The other one happened earlier this year at about 125k, where the radiator tank cracked and the car was driven for a few days with a leaking radiator, though I'm not sure if the car was truly overheated during this incident.

This engine has aluminum heads and an aluminum block, so I'm sure that it does not take overheating very kindly. Given the number of overheats that has occurred, how do I know if this engine is toast? Should I just keep an eye out for "milkshake" like engine oil in the crankcase?

 

[Corvette Owner]

Yes,look for water in the oil that would show a blown head gasket (also bubbling in the radiator, lost of coolant, and white smoke from exhaust). Other than doing a compression test (piston ring wear/loosing temper), not sure what else you can do?

 

[PT1]

Originally Posted By: The Critic
My mom did not know where the steam was coming from, so she finished off her highway commute despite the massive amount of steam from the underhood area.


Don't feel bad...my wife would see the steam and when the red light came on in the instrument cluster she would just figure "coffee's ready"

Run a 3000-5000 OCI and do a UOA on the oil and look for coolant, water, maybe a bird's nest.

 

[Trav]

Some engines endure this sort of thing better than others.
Engines with dissimilar metals seem to have more trouble when over heated.
I wouldn't even venture a guess as to how many times.
What's been posted sounds like sound advice to me. Time will tell.

 

[mechtech2]

When the owl was asked how many licks does it take to eat a tootsie roll pop, he concluded it took 3. Obviously, it could have been more or less.
One good overheat is usually enough to do damage.
But if you simply mean the temp got higher than normal, you'll be OK.
Pure luck is involved.
If your coolant does not goes down, your oil stays clean, and it is not misfiring, it is a very good sign.

 

[Tosh]

To answer the question, I would have said 'zero,' but that doesn't seem right in the case of your car, Critic.

As has been said, look out for oil and coolant exchange in both directions, and hope for the best. Might run a compression test?

 

[eljefino]

I bought a $150 saturn where the tensioner failed, no accessories spun, and the dude drove it until the battery went flat. All systems were go, it even burned lots of oil like they all do!

Did your mom mention the blinky low coolant warning lights? They are hard to miss, if also hard to decipher.

 

[mechanicx]

I think once if it overheated bad, and you will have a warped or cracked head. Overheating also cooks gaskets and seals.

There's two kinds of overheating. The kind caused by an initial coolant loss is slightly worse I think. Parts of the engine get hotter quicker. This could be from a leak, blown hose, waterpump etc.

The other is not from initial coolant loss and caused by a thrown belt or stuck thermostat. This probably overheats slightly less quickly and intense at first. But either way once the coolant gets hot enough to boil over you loose coolant and it makes no difference really.

So it all depends on just how hot it got. If the car stalled while overheating, it probably ruined the motor. Even if the overheating didn't blow the head gasket, it might have shorten the life of seals and gaskets and increased oil consumption. The oil should be changed after fixing the cooling system problem.

If a car is running hot, first turn the A/C off and the heater up but always shut an engine down right away if it nears the red and/or boils over.

 

[1993_VG30E_GXE]

Last night the area around my radiator was getting slightly steamy (or smokey I couldn't tell) when I was 10 degrees over advanced during my testing (idling). The coolant gauge on the dash board remained in the center. The car was still on jack stands. I immediately turned it off, and water or coolant, I couldn't tell, was possibly pooling on the bottom of the radiator a bit, slightly. The fans would periodically kick in and the smokyness would go away slightly, then the fans would turn off and the smokyness stopped. A couple of tiny hoses from the PCV valve area on the plenum are slightly leaking and I ordered the clamps for those, but I wouldn't think that coolant falling onto the manifold would end up close to the radiator right?

Is this an overheating scenario IF THE GAUGE NEVER MOVES INTO THE DANGER ZONE?

 

[mechanicx]

Originally Posted By: 1993_VG30E_GXE
Last night the area around my radiator was getting slightly steamy (or smokey I couldn't tell) when I was 10 degrees over advanced during my testing (idling). The coolant gauge on the dash board remained in the center. The car was still on jack stands. I immediately turned it off, and water or coolant, I couldn't tell, was possibly pooling on the bottom of the radiator a bit, slightly. The fans would periodically kick in and the smokyness would go away slightly, then the fans would turn off and the smokyness stopped. A couple of tiny hoses from the PCV valve area on the plenum are slightly leaking and I ordered the clamps for those, but I wouldn't think that coolant falling onto the manifold would end up close to the radiator right?



Is this an overheating scenario IF THE GAUGE NEVER MOVES INTO THE DANGER ZONE?


I don't think this was an overheating situation. Assuming your gauge works fairly correct, it has to get pretty much near the red to overheat or at least be pretty low on coolant. I'm not sure what the layout of this car is or what car it is, but if coolant drips on to the engine or exhaust it can smoke, or any leaking area can throw off some steam. Altering your ignition timing can make the engine run hotter.

 

[eljefino]

The only thing one should be concerned about is if they lose coolant the temp sensor might be IN AIR and not having the extreme heat conducted to it properly. Then it would read falsely.

The OP's Saturn has a low coolant warning light, a great and overdue idea.

 

[Saturn_Fan]

Originally Posted By: eljefino
The only thing one should be concerned about is if they lose coolant the temp sensor might be IN AIR and not having the extreme heat conducted to it properly. Then it would read falsely.

The OP's Saturn has a low coolant warning light, a great and overdue idea.


+1, And the light works slick too. I was flushing the radiator on my 00 SL1 and didn't fill it up all the way and started the car. Within a few seconds the little low coolant icon appeared.

 

[javacontour]

Originally Posted By: The Critic
My mom and I share a '96 Saturn SL2. Current mileage is about 136k.

Recently, the car was overheated for a third time. A radiator hose had a slight leak, which resulted in a cloud of steam from the hood during a morning highway commute. My mom did not know where the steam was coming from, so she finished off her highway commute despite the massive amount of steam from the underhood area. The highway commute probably lasted for another 20 miles or so at low-speeds. Later that day, my dad fixed the hose, refilled the cooling system and claims the car works fine.

There has also been two previous incidents. One incident was at the 60k mark, where the serpentine belt tensioner failed and the car was driven for about 10 miles without a fully functional water pump. The other one happened earlier this year at about 125k, where the radiator tank cracked and the car was driven for a few days with a leaking radiator, though I'm not sure if the car was truly overheated during this incident.

This engine has aluminum heads and an aluminum block, so I'm sure that it does not take overheating very kindly. Given the number of overheats that has occurred, how do I know if this engine is toast? Should I just keep an eye out for "milkshake" like engine oil in the crankcase?


So much for rebuilding a cooling system at 90K as you suggested in another thread.

But seriously, sorry about the problems. It just goes to show you that even being proactive may not protect.

A 96 Saturn, I'd probably just fix it and keep an eye on it, Check the coolant weekly and/or at every fill up when you check the oil as suggested.

Stuff happens, cars break and we have to be ready.

 

[DoubleDee]

You have been extremely lucky. If you have the DOHC that is your saving grace. The heads for the SOHC are known to crack in the first overheat. My daughter just did that to hers. It had oil in the coolant. I had to replace the head.

 

[mechanicx]

Originally Posted By: eljefino
The only thing one should be concerned about is if they lose coolant the temp sensor might be IN AIR and not having the extreme heat conducted to it properly. Then it would read falsely.

The OP's Saturn has a low coolant warning light, a great and overdue idea.


You know in the past I've thought about the temp sensor being in air and may not read the temperature, and I assumed that the it is screwed into a hot area into metal and the metal is going to be as hot or hotter than the coolant and a good conducter. But I'm not really sure whether or not there needs to be liquid at the sensors tip for it to measure temperature accurately since it's screwed into the metal.

 

[The Critic]

Originally Posted By: javacontour
So much for rebuilding a cooling system at 90K as you suggested in another thread.

But seriously, sorry about the problems. It just goes to show you that even being proactive may not protect.

A 96 Saturn, I'd probably just fix it and keep an eye on it, Check the coolant weekly and/or at every fill up when you check the oil as suggested.

Stuff happens, cars break and we have to be ready.


Most of the cooling system has already been overhauled, which is why I'm still puzzled as to how this happened. Until I get to see the damaged part, I'm assuming it's either road debris or a defective part.

Originally Posted By: eljefino
The only thing one should be concerned about is if they lose coolant the temp sensor might be IN AIR and not having the extreme heat conducted to it properly. Then it would read falsely.

The OP's Saturn has a low coolant warning light, a great and overdue idea.


My mom didn't mention anything about a low coolant light, but I don't know if she knows what that is.

 

[asiancivicmaniac]

I'm really proud of my mom now. I was doing a few drain and fills of the coolant on the family van over the summer. I didn't fill it up enough with water before she drove to work that afternoon. The temp gauge shot up and she immediately called me and parked the car.

 

[The Critic]

Originally Posted By: asiancivicmaniac
I'm really proud of my mom now. I was doing a few drain and fills of the coolant on the family van over the summer. I didn't fill it up enough with water before she drove to work that afternoon. The temp gauge shot up and she immediately called me and parked the car.


My mom will keep driving until the car either a) catches on fire or b) stops running and will not restart.

 

[1993_VG30E_GXE]

That's the norm critic. You should see how ladies (mom for example and girls I know) kill trannies to death. I swear, I think car manufacturers have to build reliability factors purely for the women who drive them. They are the ultimate test for reliability.

Watch when girls drive - they do this all the time = They roll backwards slowly in reverse, then go into drive when it's still rolling backwards. I'm not sure if the cars today can handle that, but to me it seems like it would be hard on it