Thermagasket

[rfishing]

Originally Posted by mtflight

On aluminum engines, the supplement tabs are prescribed to prevent / correct leaks due to casting porosities. It may be leaking out at the crossover pipe or somewhere else. Do an advanced search on the forum here... many different cases of "mysterious" leaking--some originally mistaken for headgasket failures.

Steam in tail pipe would imply it IS the headgasket. It could be leaking, for example, between the engine and the firewall, externally. The engine is hot enough that it evaporates and never makes it to the ground. This is where the Goldenseal powder (or supplement tabs) excels.

EDIT: the "coolant level low" message takes place when your reservoir is empty. 1/2 gallon apparently isn't low enough to trigger it.

If I understand you correctly, the advice at this point is to:

1. Pressure test system.

2. If no leaks are found, add coolant with supplement tabs as I did in the beginning.

I have to read up on cross over pipe

[Jesda]

On water and coolant, question C:

Antifreeze does not transfer heat from metal surfaces as effectively as distilled water. When I had radiator problems with my Q45, I used 100% water temporarily to stave off high temps until I could order new parts.

Products line Redline Water Wetter can help, and I can testify that it does work in extreme conditions like Arizona highway driving or in a failing cooling system. Autozone has it for $8. Its not magic; what it does is lower the surface tension of water, allowing for better thermal transfer.

Antifreeze is required for normal use, at least 20% in the summer, to prevent corrosion. It contains additives that protect your water pump, thermostat, hoses, and radiator.



Pressure is what increases the boiling point of water, not antifreeze. Antifreeze will reduce it. If 15lbs of pressure cannot be maintained, the coolant mix will boil sooner and fluids will be lost.
^^Someone correct me if I'm wrong on that last bit. I might be wrong.

[mcowden]

Originally Posted by rfishing

After sleeping on this, I am reconsidering the boiling point of water under pressure theory.

1. We add coolant to keep water from boiling, and if you check the coolant with a tester, it tells you that you now have increased the boiling point up to 250-260 degrees.

2. Is the system really under 15 pounds of pressure, or is it designed to relieve pressure at 15 pounds. I am thinking system is not under 15 pounds of pressure unless there is a problem, that is why the radiator cap is designed to relieve pressure at 15 pounds.

3. What is the normal operating pressure inside an engine? Without knowing that pressure I cannot assume the boiling point of water.

I checked my notes. When I test drove the car, the temperature seemed to hold fairly well in the beginning stages of test drives. It was after stressing the engine with rapid excelerations that the temperature increased.

Questions I am now asking are;

A. Could it be that the water began boiling over at this point of rapid exceleration?

B. Is it possible to boil over 1/2 a gallon in just a few minutes?

C. If I drain water, and fill with antifreeze will this solve the problem, or will I be right back to the beginning with this mysterious head gasket problem?

As you may have noticed, things expand when they heat up. A cooling system is subject to the same physical laws that govern everything else in the universe. As the cooling system contents heat up (i.e. the car is running), they expand. As they expand, the pressure goes up. When the pressure reaches 15 pounds, the cap opens up a little bit to let the contents of the top of the surge tank escape through the drain hose. The contents of the top of the surge tank is mostly air unless the tank is overfilled. So the cap lets air out of the surge tank until the pressure stabilizes at 15 pounds. As the temperature fluctuates while the engine is running, the cap will let a little in or a little out to stabilize the pressure at 15 pounds. So that is to say that it doesn't take very long to raise the pressure to 15 pounds and once it gets there, it should stay there if the cap is functioning properly.

If a head gasket is breached and allowing exhaust gases into the cooling system, it's going to raise the cooling system pressure because the engine is pushing the exhaust through the gasket breach at pressures much higher than 15 PSI. Those exhaust gases in the system are going to force coolant out of the surge tank cap, reducing the amount of coolant in the system and replacing it with exhaust gases. These pressure spikes also place a lot of stress on other cooling system components. Those gases will be purged from the fluid flow circuit by the vapor vent line and wind up in the surge tank at some point, but while they are flowing through the circuit, they aren't cooling anything. As this continues to happen, more and more coolant is pushed out of the system and replaced by exhaust gases. At some point, there is not enough coolant to cool the engine and the pump will not work properly because of the cavitation. The coolant temperature will rise very quickly. If a gas bubble gets to the coolant temperature sensor, the sensor is close to the exhaust manifold which will become very hot and the sensor may read an extremely high temperature as a result.

If the system is full of nothing but water at 15 PSI while the engine is running at full temperature, it will boil at some point, but that shouldn't happen until about 253 degrees F. Coolant raises this boiling point a bit further. If the coolant temperature shows it's under 250 degrees, it's probably not boiling but being forced out of the system by the breached head gasket allowing exhaust gases into the system. That assumes of course that the cap is rated for 15 PSI and working properly.

The point is, rfishing, it's likely your head gasket is a goner. You could get the cylinder compression test done, as Ranger suggested yesterday, to know for sure, but I'd say you should assume it's gone if there are no other leaks in the system.

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[Ranger]

PLEASE, end the agony and do a cylinder leak down test. That is the only way to find out for sure whether the head gaskets are toast or not.

[rfishing]

Originally Posted by Ranger

PLEASE, end the agony and do a cylinder leak down test. That is the only way to find out for sure whether the head gaskets are toast or not.

If I understand correctly, that test requires shop air of 120 psi? I do not have that.

Learn something new everyday. So pressure is increasing with temperature gradually inside the engine, and thats how it raises the boiling point. Okay, its making more sense now. Still waiting on the ThermaGasket, for intial diagnosis was a Blown Gasket.

I guess bottom line is, the lower radiator hose was loose, and that cause the original coolant loss, which led to blowing of gasket and stressing of the radiator cap.

Strange that I never saw a drop of coolant on garage floor, or any steam leaks. Even the area around the lower radiator hose was clean, even cleaner after I flushed.

[mcowden]

Originally Posted by rfishing

If I understand correctly, that test requires shop air of 120 psi? I do not have that.

Learn something new everyday. So pressure is increasing with temperature gradually inside the engine, and thats how it raises the boiling point. Okay, its making more sense now. Still waiting on the ThermaGasket, for intial diagnosis was a Blown Gasket.

I guess bottom line is, the lower radiator hose was loose, and that cause the original coolant loss, which led to blowing of gasket and stressing of the radiator cap.

Strange that I never saw a drop of coolant on garage floor, or any steam leaks. Even the area around the lower radiator hose was clean, even cleaner after I flushed.

It sounds like there are two things that need to be done at this point. First is to get the cylinder pressurization test done by someone who DOES have access to 120 PSI shop air. If the cylinder pressurization test comes out negative for a head gasket breach, the second is to to carefully inspect the entire cooling system for leaks. The hose clamp was one. Maybe there's a pinhole leak in a hose or the water pump cover is leaking or the water pump bearing seal is leaking or the radiator is leaking.

[SteveThefolkie]

Originally Posted by rfishing

MTFlight,

1. I live in southern california desert, so temps outside temp is in 70s. Goes down to mid 40s at night.

2. If not boiling, where is the water going?

3. I never see steam in tail pipe.

4. I never see coolant level low messages. I have not seen those since Head Gaskets were replaced 16k miles ago.

... one thing to consider with the boiling point - if you live in at an altitude that's significantly above sea level, the boiling point of water drops as the atmospheric pressure drops - however - to boil off 1/2 gallon of water would take some doing.

[rfishing]

Originally Posted by SteveThefolkie

... one thing to consider with the boiling point - if you live in at an altitude that's significantly above sea level, the boiling point of water drops as the atmospheric pressure drops - however - to boil off 1/2 gallon of water would take some doing.

I am at 4000 feet elevation. I found a calculator and my boiling point of water is 204.62 degrees.

Hmm...

[mtflight]

The 120 psi test per chamber is an aide in finding out "where" the breach is (i.e., what bank, which cylinder, etc).

The 120 psi would breach the headgasket and show up as bubbles in the reservoir tank. 120 psi is not anything like the actual psi in the compression chamber from engine operation--that is significantly higher. So I don't see how you would see much bubbling, compared to revving the engine and watching for the same bubbles.

The 15 psi test, with the cooling system pressure tester, is the easier test.

It only involves keeping the pressure up for a few hours, then rotating the engine with the starter and the spark plugs outand watching for coolant spewing from the spark plug ports.

You can get the cooling system pressurizer at Autozone under the loan-a-tool program for a $75 deposit (100% refundable). Could someone please clarify if it's that simple? The great Rob posted that.

[rfishing]

Does it make sense, that if I take out spark plugs, and find one that is discolored or white, along with the 2 positive combustion gas leak tests, and the loss of coolant, that I would have enough evidence to support a blown head gasket affecting that particular cylinder?

[mtflight]

Originally Posted by rfishing

Does it make sense, that if I take out spark plugs, and find one that is discolored or white, along with the 2 positive combustion gas leak tests, and the loss of coolant, that I would have enough evidence to support a blown head gasket affecting that particular cylinder?

Sure but it's not really conclusive. It's evidence, but it could also mean other things.

The expert that we had here a while back posted the solutions I relayed. He really believed in the 15 psi cooling system pressurizing for hours, then turning the engine with the starter and the spark plugs out--looking for coolant.

That test is definitely conclusive. So quit speculating and do it if you want to know for sure.

[Ranger]

The only problem with pressuizing the cooling system is that if it turns up negative, it is still possible to have a head gasket problem that has not gotten bad enough to be breached by 15 psi.........yet. A positive result, on the other hand, is conclusive.

If you don't have shop air, this is the next best test and at least a good start. Do it.

[rfishing]

Got the ThermaGasket Kit finally. The first order was lost in mail, and they sent this one out yesterday. Talked to rep about my situation. He told me they have traveled around the country demonstrating this product for 9 years, and used it successfully on numerous Norstars. He also added, that if Gas was detected in the coolant, then that is the bottom line and there is a need to fix it. I am quoting him, "No mater what anybody tells me, that is a reliable test."

I asked, if after using this product, I later decide to replace headgaskets, or rebuild engine, will it be a problem? The answer was No problem at all.

I drained my radiator again today, refilled with water in preparation for tomorrows big day with ThermaGasket. During the refill process, out of curiousity, I looked for signs of bubbling in the overflow tank, and surprised that I did not see anything except a few random bubbles from equalization. I checked every hose clamp at 220 degrees while idling, and all were tight, with no leaks.

Tomorrow I hope to get a pressure tester from Autozone, and do a quick check of the system prior to using ThermaGasket.

I am by myself doing this so tell me, how can I run engine at 2500 rpms, and look in coolant for signs of exhaust bubbles in the pressure tank? On my other cars, there was a link up to the carburator. I cannot find a way on this car with injection 94 Seville STS. I was thinking that under load, or with higher rpms the gas bubbles should appear.

[Kev]

Originally Posted by rfishing

I am by myself doing this so tell me, how can I run engine at 2500 rpms, and look in coolant for signs of exhaust bubbles in the pressure tank? On my other cars, there was a link up to the carburator. I cannot find a way on this car with injection 94 Seville STS. I was thinking that under load, or with higher rpms the gas bubbles should appear.

You should be able to fine the throttle plate, just follow along from the air cleaner and you will see the plate where your throttle cable ist attched. You will have to guess the RPM unless you connect a tach to it.

[mtflight]

Originally Posted by rfishing

Got the ThermaGasket Kit finally. The first order was lost in mail, and they sent this one out yesterday. Talked to rep about my situation. He told me they have traveled around the country demonstrating this product for 9 years, and used it successfully on numerous Norstars. He also added, that if Gas was detected in the coolant, then that is the bottom line and there is a need to fix it. I am quoting him, "No mater what anybody tells me, that is a reliable test."

I asked, if after using this product, I later decide to replace headgaskets, or rebuild engine, will it be a problem? The answer was No problem at all.

I drained my radiator again today, refilled with water in preparation for tomorrows big day with ThermaGasket. During the refill process, out of curiousity, I looked for signs of bubbling in the overflow tank, and surprised that I did not see anything except a few random bubbles from equalization. I checked every hose clamp at 220 degrees while idling, and all were tight, with no leaks.

Tomorrow I hope to get a pressure tester from Autozone, and do a quick check of the system prior to using ThermaGasket.

I am by myself doing this so tell me, how can I run engine at 2500 rpms, and look in coolant for signs of exhaust bubbles in the pressure tank? On my other cars, there was a link up to the carburator. I cannot find a way on this car with injection 94 Seville STS. I was thinking that under load, or with higher rpms the gas bubbles should appear.

Located on the driver's side, is the throttle body. It's connected to the air intake housing, etc. Feeding into it are the throttle cable and the cruise control cable. You can do the same as you did with your other cars.

The high RPM should bring combustion gases into view through the tank, if indeed you have a headgasket issue.

Since you've had your car Timeserted, I have doubts that your headgasket is bad--my opinion.

Regarding the exhaust gas test, you said the mechanic pulled out early, before the strip changed colors "fully," and gave you some half-ass excuse. He may be the same one that said you should not pressurize the cooling system--which is BS. Do you trust your mechanic? The Thermagasket sales rep, does not forget who pays his bills either--of course.

Either way I think you smell success here soon, good luck!