BigGunna said:
Oh man, you are in a sticky situation.
I see bubbles! Oil consumption too!
- Thread starter Altaf
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Oh man, you are in a sticky situation.
Do you have your old oil around? You might also call your dealer and express your concerns and ask how THEY will confirm a head gasket issue. If they say it can only be determined by teardown, then continue the discussion into what will satisfy the warranty that you can provide (sniffer in the overflow bottle, oil analysis, etc).
DougM
DougM
- Thread starter
- #23
Unfortunately the tech at this dealership dispensed the oil in their common container when he did the oil change, even though I told them about the consumption issue. Guess the tech didn't pay much mind to what I told him.
The dealership uses a pressure test ($100) to determine if the head gasket is leaking. According to Pat Goss, the pressure testing method only tests positive if there is a massive leak. He recommends using the emissions method.
The Pat Goss article I read was very informative to me, so I'm going to link the article as well as copy it's contents below (in case the linked content gets removed one day).
-----
PAT GOSS
Certainly sounds as if a blown head gasket is a distinct probability. You didn't mention anything about coolant contaminating the oil or oil contaminating the coolant, and this is a good thing. Here's the way you go about proving or disproving.
First is to clear away the old misconceptions that when a head gasket fails, coolant will go into the oil or oil will go in the coolant. It's been my experience that those symptoms only occur in about 2% of the head gasket failures we come in contact with.
What we more typically find is overheating or a fluctuating temperature gauge or forceful ejection of coolant from the radiator or no heat from the heater. It could be any one of these symptoms or a combination of any or all of them.
All right, now, let's see. The next misconception to do away with is that pressure testing the cooling system is a good way to identify a head gasket problem. IT IS NOT. The more common form of head gasket failure is where combustion gases under extreme pressure leak past a defect in the head gasket and enter the cooling system. Because combustion pressures are much higher then cooling system pressures, this causes liquid coolant to be forcefully expelled from the cooling system and the lost coolant to be replaced by exhaust gas. The gases are not an effective coolant therefore the overheating. The gases are not a good conductor of heat, so every time a pocket of gas passes over the coolant temperature sensor, the temperature gauge drops. And every time the heater core is filled with gas, there's no heat from the heater.
Now, on to why pressure testing is NOT a valid test for the typical head gasket failure. It's very ineffective because the maximum pressure which can be safely applied to the cooling system is less than 20 pounds. In contrast, combustion pressures are in the hundreds of pounds. Add to that the fact that molecules of coolant are enormous in size compared to the molecules of exhaust gas. Thus it becomes readily apparent that the higher pressure and smaller molecules of gas can be pushed through a defect much too small for the larger molecules and lower pressure within the cooling system.
If pressure testing is not valid what is a valid test for a blown head gasket? An exhaust gas analyzer!
The test is simple. The car is thoroughly warmed up with the radiator cap removed. The engine is held at a fast idle normally 1500 to 1800 rpm and the exhaust gas sensing probe (piece normally placed in the tailpipe) is held about an inch above the open radiator filler neck. Watch the hydrocarbon scale on the tester. If the hydrocarbon readings increase noticeably the engine has a bad head gasket. There should never be exhaust in the cooling system and there is only one way for it to get there, a bad head gasket. Please note: EXTREME caution must be used to prevent even the smallest amount of coolant from entering the sample tube. If coolant is inadvertently drawn into the exhaust gas analyzer it can instantly cause hundreds to thousands in damage to the tester.
I repeatedly receive inquiries about possible head gasket failures, frequently the car has been to multiple repair shops where it has been tested and retested, seven ways from Sunday, with no conclusive answers. Waste of time. Waste of money. Many times there's also extensive damage to the engine from repeated overheating.
The exhaust gas test is quick, normally less than 10 minutes and is highly accurate. Naturally it would still be prudent to run a pressure test, which would disclose massive leaks, but if the pressure test is inconclusive proceed immediately to the exhaust gas test. End of story.
http://www.garage-pak.com/pat-goss-corvette-corner/february-2003-corvette-corner.html
The dealership uses a pressure test ($100) to determine if the head gasket is leaking. According to Pat Goss, the pressure testing method only tests positive if there is a massive leak. He recommends using the emissions method.
The Pat Goss article I read was very informative to me, so I'm going to link the article as well as copy it's contents below (in case the linked content gets removed one day).
-----
PAT GOSS
Certainly sounds as if a blown head gasket is a distinct probability. You didn't mention anything about coolant contaminating the oil or oil contaminating the coolant, and this is a good thing. Here's the way you go about proving or disproving.
First is to clear away the old misconceptions that when a head gasket fails, coolant will go into the oil or oil will go in the coolant. It's been my experience that those symptoms only occur in about 2% of the head gasket failures we come in contact with.
What we more typically find is overheating or a fluctuating temperature gauge or forceful ejection of coolant from the radiator or no heat from the heater. It could be any one of these symptoms or a combination of any or all of them.
All right, now, let's see. The next misconception to do away with is that pressure testing the cooling system is a good way to identify a head gasket problem. IT IS NOT. The more common form of head gasket failure is where combustion gases under extreme pressure leak past a defect in the head gasket and enter the cooling system. Because combustion pressures are much higher then cooling system pressures, this causes liquid coolant to be forcefully expelled from the cooling system and the lost coolant to be replaced by exhaust gas. The gases are not an effective coolant therefore the overheating. The gases are not a good conductor of heat, so every time a pocket of gas passes over the coolant temperature sensor, the temperature gauge drops. And every time the heater core is filled with gas, there's no heat from the heater.
Now, on to why pressure testing is NOT a valid test for the typical head gasket failure. It's very ineffective because the maximum pressure which can be safely applied to the cooling system is less than 20 pounds. In contrast, combustion pressures are in the hundreds of pounds. Add to that the fact that molecules of coolant are enormous in size compared to the molecules of exhaust gas. Thus it becomes readily apparent that the higher pressure and smaller molecules of gas can be pushed through a defect much too small for the larger molecules and lower pressure within the cooling system.
If pressure testing is not valid what is a valid test for a blown head gasket? An exhaust gas analyzer!
The test is simple. The car is thoroughly warmed up with the radiator cap removed. The engine is held at a fast idle normally 1500 to 1800 rpm and the exhaust gas sensing probe (piece normally placed in the tailpipe) is held about an inch above the open radiator filler neck. Watch the hydrocarbon scale on the tester. If the hydrocarbon readings increase noticeably the engine has a bad head gasket. There should never be exhaust in the cooling system and there is only one way for it to get there, a bad head gasket. Please note: EXTREME caution must be used to prevent even the smallest amount of coolant from entering the sample tube. If coolant is inadvertently drawn into the exhaust gas analyzer it can instantly cause hundreds to thousands in damage to the tester.
I repeatedly receive inquiries about possible head gasket failures, frequently the car has been to multiple repair shops where it has been tested and retested, seven ways from Sunday, with no conclusive answers. Waste of time. Waste of money. Many times there's also extensive damage to the engine from repeated overheating.
The exhaust gas test is quick, normally less than 10 minutes and is highly accurate. Naturally it would still be prudent to run a pressure test, which would disclose massive leaks, but if the pressure test is inconclusive proceed immediately to the exhaust gas test. End of story.
http://www.garage-pak.com/pat-goss-corvette-corner/february-2003-corvette-corner.html
If dealer says all is fine and you can not show a HGF situation before warranty expires you might consider purchasing an extended warranty. A further 12 months should be cheap in your situation.
- Thread starter
- #25
Test results negative
I had a local service station test for a bad head gasket today. Results are negative
!
They used a sniffer test, compression test, and examined the #6 spark plug. They also looked at all the hoses to make sure there was no leak. Nothing they found showed any signs of a bad head gasket. I'm now wondering about my bubble test results. My coolant over flow tank definitely bubbles as described in my previous post. I even filmed it using my camcorder, but I haven't been able to find free software to convert the tape to an .avi or .mpg file. Otherwise I would have hosted the video so everyone could see what I'm seeing. I'm curious what else could be the causing bubbles - could it be considered normal?
I'm much more at ease after getting these tests done. I'm still going to be monitoring the oil and coolant levels very closely every week.
I had a local service station test for a bad head gasket today. Results are negative
!They used a sniffer test, compression test, and examined the #6 spark plug. They also looked at all the hoses to make sure there was no leak. Nothing they found showed any signs of a bad head gasket. I'm now wondering about my bubble test results. My coolant over flow tank definitely bubbles as described in my previous post. I even filmed it using my camcorder, but I haven't been able to find free software to convert the tape to an .avi or .mpg file. Otherwise I would have hosted the video so everyone could see what I'm seeing. I'm curious what else could be the causing bubbles - could it be considered normal?
I'm much more at ease after getting these tests done. I'm still going to be monitoring the oil and coolant levels very closely every week.
I would think that the most obvious reason you could see bubbles in your overflow tank, besides a bad HG, is if you opened the radiator cap or drained the coolant recently.
(of course, also if your shop refilled it with Champagne instead of distilled water... most likely if it's a Lexus...
)
(of course, also if your shop refilled it with Champagne instead of distilled water... most likely if it's a Lexus...
)
On October 24 I told you "Because you changed the oil and the coolant you may have left ullage on both counts." Until you correctly fill and purge the cooling system you will get bubbles and apparent loss. That's why I told you to fill it right, run it hot and re adjust levels when cold, then start to look for coolant and oil losses.
The air in the cooling system looks like it is there because you keep taking the cap of of the radiator or did not purge trapped air after the flush, and the low oil seems to be just because it was not filled up at your oil change. Get the oil and water levels right then leave them alone - just check the cold levels daily and I think you will be OK. Glad you don't have a HG problem.
The air in the cooling system looks like it is there because you keep taking the cap of of the radiator or did not purge trapped air after the flush, and the low oil seems to be just because it was not filled up at your oil change. Get the oil and water levels right then leave them alone - just check the cold levels daily and I think you will be OK. Glad you don't have a HG problem.