Thermagasket

[mtflight]

If the temperature does climb above 230, pull over, open the hood, and idle with the A/C on. I think that lowers the temperature faster than turning it off. Results may vary.

I think that won't be necessary though, and hopefully your car will give you another 100 K or more of service.

[sjwoodruff]

I don't know that I've ever heard of this particular 'gas in the coolant' test, though that doesn't mean it isn't accurate. From the sounds of it the unit detects vapors? If that is the case, I wouldn't expect a service bay inside a shop to be the most accurate locale to use such a device - just my 2 cents on that one.

Give it a short, normal drive. If all seems well, run it up a steep hill and see what happens. I'm betting it won't start to overheat or lose coolant. Maybe you won't even need the Thermagasket treatment. I'd be willing to bet that you were dumping coolant out of the lower hose all along. Sometimes the most obvious solution to a problem is the one that gets overlooked.

And another thing...while there is only water in the coolant system, take care that freezing temperatures don't occur, or you could have real problems on your hands. Good luck.

[mcowden]

Originally Posted by mtflight

If the temperature does climb above 230, pull over, open the hood, and idle with the A/C on. I think that lowers the temperature faster than turning it off. Results may vary.
I think that won't be necessary though, and hopefully your car will give you another 100 K or more of service.

Yikes! I wouldn't run the A/C to help cool it off. If the A/C is running, it will pull hotter air across the radiator from the evaporator, plus the added load of the compressor running. If it's hot, the fans will be running anyway so the A/C won't help there. To cool it off, run the heat at highest temperature highest fan speed to use the heater core as an additional radiator. Hopefully it will never come to that.

[mtflight]

Originally Posted by mcowden

Yikes! I wouldn't run the A/C to help cool it off. If the A/C is running, it will pull hotter air across the radiator from the evaporator, plus the added load of the compressor running. If it's hot, the fans will be running anyway so the A/C won't help there. To cool it off, run the heat at highest temperature highest fan speed to use the heater core as an additional radiator. Hopefully it will never come to that.

Ahh... good call.

My observation was completely empirical. When my A/C is off, temperatures fluctuate from 196 up to 220. With the A/C on, they tend to stay from 192-203. Idleing with the A/C on, they will go back down to 196. I was thinking of the added benefit of the extra fan going... but you're probably right in that if the temperature goes above 220 the fans would come on anyway.

[Ranger]

Originally Posted by rfishing

3. Since no coolant is in system, what keeps the water from boiling at 212 degrees?

Pressure.
http://www.chem.purdue.edu/gchelp/liquids/boil.html

[rfishing]

Took for a test drive, and now scratching my head.

First of all, I flushed one more time while it was cold today. Sure enough more coolant came out. Top off coolant, started engine with cap off. Running smooth as sewing machine. Noticed water level rising and falling, so added water until at the 2 inch below cap level while hot and running at 195degrees for a few minutes. Put cap back on, and went for drive.

Temperature at first was normal 192-207 with AC on and at stop lights. 2 miles from my house I pulled in for gas, and checked, found no leaks.

Drove a 4 mile stretch of road at 55 mph, temp never went above 204. More long stop lights with AC on and temp stayed below 207.

Went back that 4 mile stretch of road, and gave it a bit more peddle this time, hit 3000 rpms while excelarating to 50 mph, I only hit it for about 4 seconds. Due to traffic I couldnt go faster. No sooner than I hit 3000 rpms the temp took a shart increase to 223 degrees, so I let up on peddle to observe temp reading.

While basically coasting, at 40 mph the remaining 3 mile stretch, temp rose slowly up to 232, I was close to returning to my exit home, so decided to turn out. At turn out road inclines dramatically for tenth of mile, I figured on pulling over but suddenly temp dropped to below 220.

Less then mile later, and all flat traveling, I am home again. Temp is at 210 when I pulled in driveway. Immediately checked for overflow, and found none. Not a drop of water anywhere.

Im thinking that I am right back to where I started in the very beginning. That If I take her up the mountain she will overheat? That the excessive amounts of Bars leak Tabs contributed to overflowing coolant problem?

Some Feed back please.

Oh and a quick note, it has to be in Econo Mode or AC unit will continue to run even though heat is selected. Something about humidity control makes Ac unit stay on. I noticed this before Ac unit was cold when heat was selected in Auto mode.

[rfishing]

Another note. Engine is cool now, so I checked level in overflow tank, and it took 1/2 gallon of water.

[mtflight]

Originally Posted by rfishing

Another note. Engine is cool now, so I checked level in overflow tank, and it took 1/2 gallon of water.

It may have "burped," from all the flushing. Keep checking the level on similar test-drives. There's good hope that all may be well, after all.

[Ranger]

Do the cylinder leak down test and confirm or rule out a bad head gasket.

[SteveThefolkie]

I've been following this thread with great interest, because my '92 Seville (non-northstar) is showing similar behavior. About a month ago the temp rose to 252 - got the standard "coolant hot idle engine" message on the display - being only about a tenth of a mile from the office I just slowly drove in and parked - in that time the temp dropped to 201 - idled for a couple minutes - temp stayed down - shut her off and went inside.
Worked on a machine design for four or five hours, then at lunch went out and checked the overflow tank - pretty much empty - popped the radiator cap - low on coolant - so I added some water (all I had at the time) - drove home - everything was OK.
That Saturday I replaced the thermostat (195 degree), radiator cap (16psi) and water pump (which was all gunked up) - whoever designed the waterpump should spend eternity removing and replacing them but that's another story. Filled the system with a 50/50 coolant mix - let it run until the thermostat opened - made sure the system was bled (at least I thought I did) - took it for a test drive - all was well with the world.
Yesterday (it's been a few weeks now folks) the temp again rose to 252 - warning lights - the whole deal - but I was not in a place where I could pull over - I gunned the engine (on a hunch) and the temp fell.
Given the speed at which the temperature changes, and having a fair knowledge of thermodynamics I am positive that the coolant could not change temperature that fast.
She idles fine, isn't rough at startup, no (excessive) water vapor at start up (it's been cold around here in the mornings, so there is some), hasn't lost any power and the plugs all look good (doesn't appear that there is any water or coolant fouling them) -
Could I just have an air pocket somewhere in the cooling system that's causing this to occur? I have noticed that when the temp goes up the heater ceases to blow hot air - which is leading me to speculate on the air bubble theory - that it's actually obstructing the cooling system somehow - if so - I have to admit that it's a first in 30 years of driving and working on cars -
I don't think it's a head gasket issue - she's only got 120,000 on the clock and was never beaten -
Thoughts, theories or ideas??

Thanks

Steve

[delzy]

This whole thread has gone retarded. If the great trial lawyer rfishing would have just done the leak down test instead of rattling his gums or keys for the last 2 weeks, he could have eliminated all speculation. He obviously doesn't understand the scientific method and his findings are less than worthless.

StevetheFolkie,
I might have seen your symptoms listed where people had a plugged purge line to the reservoir. But it is very interesting the irregularity of the problem. You should have your own thread and forget about Head Gasket Repair. These guys aren't even doing the minimum to diagnose thier own problems. As a matter of fact, this thread has forced me to put a couple of retards on my ignore list.

[rfishing]

Originally Posted by Ranger

Do the cylinder leak down test and confirm or rule out a bad head gasket.

Sorry to say, after researching this forum, I do not have the tools or experience enough to do a Leak Down Test.

Someone may benefit from these messages, irregardless of my lack of scientific approach, and I am learning from others on here as well. Because of your help on here, I was able to find the lower radiator hose loose, I now have a better understanding of how a cooling system functions. If someone were to read through these messages, they may benefit as well.

Orginally this was to find people that have used the BARs Leak Head Gasket, but has evolved into Thermagasket, and Bars Tablets, as none others have responded. Delzy I pray you will find forgiveness in your heart. Nobody is here to make your day.

Update:

With water level full in tank (no coolant), as requested I took for repeat test drive today. This time I left AC unit off, Heater Off. Temps stayed within 192-207 range after a few miles. I felt good about that so took her up to 4500 rpms during exceleration, and even hit 80 mph, temp did not increase until I came to stop, then temp range was normal 207 highest. Ran hard again for a few miles up to 70 mph, 4500 rpm again during the shifting. Slowly hit the brakes to slow down, did rapid exceleration again, this time temp rose up to 223. I immediately turning off highway and excelerating up a steep incline at 35 mph / 3500 rpms for tenth of mile and temp started coming down to 217, and within a half mile dropped to 210. I pulled into my driveway, opened the hood and noticed a drop of water on ground below the overflow hose. No more than just a drop, everywhere else is bone dry, rest of driveway behind car was dry as well.

In driveway, watched temp go up to 223 and fans kicked on, and brought the temp back down to 208 before shutting off. Upper hose felt hot, and mostly full. Lower hose hot, and firm.

I will check water level again after engine cools, to see if there is loss of water. With that drop on the ground, I suspect I did lose water out the overflow somewhere during the test drive. Either way, I am encouraged by the performance of this engine.

I must state, I am only test driving at this point to help others interested in this case, and to satisfy my own curiousity. Keep in mind, 2 seperate tests were performed by mechanics and they both detected combustion gases in the coolant. That alone should be reason enough to conclude a head gasket failure, cracked block, or cracked head.

ThermaGasket rep is tracking my order, and promises to send out another.
The first one was shipped on the 8th. I have relayed my problems and this same information to them, and the representative feels ThermaGasket is still needed due to Gas in coolant.

[mtflight]

Originally Posted by rfishing

Sorry to say, after researching this forum, I do not have the tools or experience enough to do a Leak Down Test.

Someone may benefit from these messages, irregardless of my lack of scientific approach, and I am learning from others on here as well. Because of your help on here, I was able to find the lower radiator hose loose, I now have a better understanding of how a cooling system functions. If someone were to read through these messages, they may benefit as well.

Orginally this was to find people that have used the BARs Leak Head Gasket, but has evolved into Thermagasket, and Bars Tablets, as none others have responded. Delzy I pray you will find forgiveness in your heart. Nobody is here to make your day.

Update:

With water level full in tank (no coolant), as requested I took for repeat test drive today. This time I left AC unit off, Heater Off. Temps stayed within 192-207 range after a few miles. I felt good about that so took her up to 4500 rpms during exceleration, and even hit 80 mph, temp did not increase until I came to stop, then temp range was normal 207 highest. Ran hard again for a few miles up to 70 mph, 4500 rpm again during the shifting. Slowly hit the brakes to slow down, did rapid exceleration again, this time temp rose up to 223. I immediately turning off highway and excelerating up a steep incline at 35 mph / 3500 rpms for tenth of mile and temp started coming down to 217, and within a half mile dropped to 210. I pulled into my driveway, opened the hood and noticed a drop of water on ground below the overflow hose. No more than just a drop, everywhere else is bone dry, rest of driveway behind car was dry as well.

In driveway, watched temp go up to 223 and fans kicked on, and brought the temp back down to 208 before shutting off. Upper hose felt hot, and mostly full. Lower hose hot, and firm.

I will check water level again after engine cools, to see if there is loss of water. With that drop on the ground, I suspect I did lose water out the overflow somewhere during the test drive. Either way, I am encouraged by the performance of this engine.

I must state, I am only test driving at this point to help others interested in this case, and to satisfy my own curiousity. Keep in mind, 2 seperate tests were performed by mechanics and they both detected combustion gases in the coolant. That alone should be reason enough to conclude a head gasket failure, cracked block, or cracked head.

ThermaGasket rep is tracking my order, and promises to send out another.
The first one was shipped on the 8th. I have relayed my problems and this same information to them, and the representative feels ThermaGasket is still needed due to Gas in coolant.

You may have overfilled the system, hence the few drops. Check the level once it's cool. Then go and test drive it again. The level should remain the same as it was when it was cool--and the leaking may stop.

If not, try a new pressure cap ($7 at a Chevy dealership), as it may be failing to pressurize fully.

I would hold of on pouring in the ThermaGasket. It's been mentioned that the exhaust gases are not fool proof. Keep in mind the holiday season is here almost, and most shops make their money upselling.

Here are the 3 ways to check for a blown headgasket:

Originally Posted by Rob

1- Start the engine cold with the pressure cap off the pressurized surge tank. Watch the coolant in the surge tank for signs of bubbling or "false boilling". If so then it may be a sign that combustion pressure is entering the system through a failed head gasket.

2- Pump up the cooling sytem pressure with a cooling system pressure tester pump. Hold it at 15 PSI for several hours. Keep pumping it up if the pressure drops. In the meantime, pull the plugs. After several hours holding pressure, rotate the engine with the starter with the plugs out. Watch for coolant spewing out from the spark plug ports as a sign of a leaking head gasket.

3- With the cooling system full, apply 120 PSI shop air to each of the combustion chambers, one at a time, through the spark plug port. Make an adapter out of an old spark plug shell and run shop air to the port. Rotate the engine so that the valves for that cylinder are closed. Watch the coolant in the surge tank for bubbling. If the chamber holds the 120 PSI with no bubbling then chances are the head gasket is fine.

You get a cooling system pressure tester with a $75 refundable deposit, at AutoZone (loan a tool program). If you're not inclined to do this... find a reputable mechanic and ask them to do this. It should not be expensive as it's just a test.. and the instructions are in the quote above.

[rfishing]

MTFlight,

You quoted this:

1- Start the engine cold with the pressure cap off the pressurized surge tank. Watch the coolant in the surge tank for signs of bubbling or "false boilling". If so then it may be a sign that combustion pressure is entering the system through a failed head gasket.

Answer: I did check for bubbling after the flush, but only saw the water level rise and fall as system equalized.

2- Pump up the cooling sytem pressure with a cooling system pressure tester pump. Hold it at 15 PSI for several hours. Keep pumping it up if the pressure drops. In the meantime, pull the plugs. After several hours holding pressure, rotate the engine with the starter with the plugs out. Watch for coolant spewing out from the spark plug ports as a sign of a leaking head gasket.

Answer: This test was adviced against by mechanic. He said, if headgasket is blown, pressurizing system might make it worst.

3- With the cooling system full, apply 120 PSI shop air to each of the combustion chambers, one at a time, through the spark plug port. Make an adapter out of an old spark plug shell and run shop air to the port. Rotate the engine so that the valves for that cylinder are closed. Watch the coolant in the surge tank for bubbling. If the chamber holds the 120 PSI with no bubbling then chances are the head gasket is fine.

Answer: Beyond my scope of tools. No shop air supply.


I doubt that I overfilled. This morning coolant level before test drive was about 2 inches below cap, with engine cold. I may be repeating everything, as this is exactly same thing that was happening in the very beginning. I will check on the radiator cap, I do see a slight bulging in the center, probably from all the overflowing. Autozone should be able to test it.

[NickySantoro]

Originally Posted by rfishing

MTFlight,



Answer: This test was adviced against by mechanic. He said, if headgasket is blown, pressurizing system might make it worst.

Crapola! If this "mechanic" did one of the combustion gas tests, discount it.

Your last post tells me you need to do some more road testing. I'm not sure you still have a problem. Verify the integrity of the cap as was previously advised.