Head gasket sealer

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TEXCHEVY

TEXCHEVY

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There is available for purchase online or at the auto parts store a product for detecting the presence of exhaust in the coolant, aka "head gasket failure" or engine block/cylinder head structural failure. Inexpensive and informative. Add purified or mineral-free water to raise the "cold fill" coolant level to the operating specs. Examine the level at least twice daily, once before the engine is first started and again several hours after the final engine shut off for the day. Inspect the fill level of the tank and also the bottom of cylinder heads and the ground for evidence of leakage. If this evidence is found or the cold fill gradually lowers without visual evidence of leakage, the combustion gas test can be performed and preparations made for service & replacement.

You haven't noticed the presence of displaced fluids on the ground underneath your truck? Have you experienced overheat episodes or fluctuation of operating temperature? Do you have access to diagnostic tools like OBD device which plugs into the socket and displays ECM info?

I've never used blue devil but I can vouch for "K-Seal"
K-Seal held off a faulty head gasket I had for over a year but like Scotty, needed a second application when I changed the coolant. If sealers are used continuously the risk of blockage in various passages becomes a threat but 1 or 2 doses is fine while you save your pennies and weigh the options. Just be certain that you properly diagnose the issue. More often than not, head gasket & structural failures occur due to ongoing overheating from faulty radiator, fan clutch, etc. On the other hand, GM did manufacture a line of faulty cylinder heads with evidence of porosity that is found on specific make/model which you will easily find via Google search. Let us know if your vehicle fits the category of bad batch cyl heads and your findings on the coolant level this week. Don't wait until it gets super hot out before repairing this.

Best time to look visually for leaks is 30-min to 1 hour after the engine is turned off. Slide underneath and look with LED flashlight, hood closed for liquids running down hoses and the engine, especially the back where transmission mates and heater hoses connect to bulkhead.

My main conclusion here, properly diagnose the issue before using any additives or sealers, OK? You don't want to add something like a radiator sealer if there is no evidence of coolant loss, be it internal or external. And then if it's external, proper removal & replacement may be the way to go. And even then, other cooling-related parts could be cause for concern and exacerbating the coolant loss or overheating conditions. Also available for purchase at harbor freight or even rental from big chain auto stores is the radiator pressure tool. It will lose pressure if the cylinder head is porous. It may or may not hold pressure depending on the damage of an actual head gasket. There are principles behind all of these diagnostics but you have to know what you are doing or further damage will result from improper DIY hacks, especially when it comes to the cooling loop. So be careful & thorough, keep the board posted and take the time to ask questions and perform research.


These are the products k-seal?

IMG_E3326.jpg IMG_E3327.jpg
 
OP
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TEXCHEVY

TEXCHEVY

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There is available for purchase online or at the auto parts store a product for detecting the presence of exhaust in the coolant, aka "head gasket failure" or engine block/cylinder head structural failure. Inexpensive and informative. Add purified or mineral-free water to raise the "cold fill" coolant level to the operating specs. Examine the level at least twice daily, once before the engine is first started and again several hours after the final engine shut off for the day. Inspect the fill level of the tank and also the bottom of cylinder heads and the ground for evidence of leakage. If this evidence is found or the cold fill gradually lowers without visual evidence of leakage, the combustion gas test can be performed and preparations made for service & replacement.

You haven't noticed the presence of displaced fluids on the ground underneath your truck? Have you experienced overheat episodes or fluctuation of operating temperature? Do you have access to diagnostic tools like OBD device which plugs into the socket and displays ECM info?

I've never used blue devil but I can vouch for "K-Seal"
K-Seal held off a faulty head gasket I had for over a year but like Scotty, needed a second application when I changed the coolant. If sealers are used continuously the risk of blockage in various passages becomes a threat but 1 or 2 doses is fine while you save your pennies and weigh the options. Just be certain that you properly diagnose the issue. More often than not, head gasket & structural failures occur due to ongoing overheating from faulty radiator, fan clutch, etc. On the other hand, GM did manufacture a line of faulty cylinder heads with evidence of porosity that is found on specific make/model which you will easily find via Google search. Let us know if your vehicle fits the category of bad batch cyl heads and your findings on the coolant level this week. Don't wait until it gets super hot out before repairing this.

Best time to look visually for leaks is 30-min to 1 hour after the engine is turned off. Slide underneath and look with LED flashlight, hood closed for liquids running down hoses and the engine, especially the back where transmission mates and heater hoses connect to bulkhead.

My main conclusion here, properly diagnose the issue before using any additives or sealers, OK? You don't want to add something like a radiator sealer if there is no evidence of coolant loss, be it internal or external. And then if it's external, proper removal & replacement may be the way to go. And even then, other cooling-related parts could be cause for concern and exacerbating the coolant loss or overheating conditions. Also available for purchase at harbor freight or even rental from big chain auto stores is the radiator pressure tool. It will lose pressure if the cylinder head is porous. It may or may not hold pressure depending on the damage of an actual head gasket. There are principles behind all of these diagnostics but you have to know what you are doing or further damage will result from improper DIY hacks, especially when it comes to the cooling loop. So be careful & thorough, keep the board posted and take the time to ask questions and perform research.

Hello Chubbs,......
today I have not found refrigerant leaks during the checks, even the heating works well. The temperature rises gradually without changes and does not rise above 90 ° centigrade (194 ° F). My Tahoe "excluding the moment of ignition and for about 20-30 seconds" does not smoke from the muffler. After the oil change the pressure of the same is fine, very well I would say.
I did not have to add refrigerant for the moment.
But I do not understand why I found refrigerant in the old oil filter (with a little-little "brown mush")
but I did not find anything in the remaining old oil
(sorry for my English :))....... )
 
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TEXCHEVY

TEXCHEVY

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last, when i turn off the engin, i listen a little gurgle about 5/6 seconds
 
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TEXCHEVY

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no, the coolant came out when I turned the oil filter upside down, and there was no coolant in the oil that was in the oil pan[/QUOTE]
 

Chubbs

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Is the reservoir currently filled to the specified mark and have you been monitoring said level for fluctuation?

Of the 2 pics you posted, I used the top/first product which worked for a faulty head gasket. It may not work for structural failures in the casting though.

You still need to verify the cylinder head castings and compare it with those known to be manufactured with defects. Some have said the identification marks are located underneath the ignition coils, which would have to be removed... Nothing but a few bolts. But you should be researching & investigating this immediately. Very important for further diagnosis.

If you are losing coolant per fill level, and finding evidence of coolant in the engine sump, verifying the ID of cylinder heads and their manufacture could ultimately determine the diagnosis. It's not 100% but this is the direction I would take, personally. It doesn't cost anything to surf the web for info. If you find the cylinder heads to match that of the bad batch, you can then source a set of used pieces for $100-$200, have them rebuilt to new specs -$200, and install them yourself with new gaskets, water pump & thermostat. This is all hypothetical assuming there is a problem with the orig C/Hs

I am giving this info because this series truck does not have a known problem of gasket failure @ cylinder head. However, there is evidence that a series of faulty cyl heads was produced so if you have cyl heads matching info available, it is more likely your prob lies with the cyl head casting itself, not the gaskets.
 
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SnowDrifter

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Know that it won't be a permanent fix


The short of it is it hardens when presented with combustion gas. Almost like an epoxy. Those little hardened bits can/will break off over time, lodging themselves in the heater core and radiator When those chemicals are used up, the product is no longer effective and now you have some work to do on the cooling system in addition to the original issue. Fine if you're in a pinch, but again: Don't view it as a long term fix. It should be repaired at the nearest opportunity

Source: Former mechanic, would have the joy of fixing the aftermath of bottle'd fixes that didn't work
 

SnowDrifter

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no, the coolant came out when I turned the oil filter upside down, and there was no coolant in the oil that was in the oil pan
[/QUOTE]
What have you tested to determine the failure point?

Some models have a cracked head issue - a hairline crack around the pushrod tubes that will push coolant into the oil in the absence of a head gasket leak
 
OP
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TEXCHEVY

TEXCHEVY

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Joined
Jan 14, 2018
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Location
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Is the reservoir currently filled to the specified mark and have you been monitoring said level for fluctuation?

Of the 2 pics you posted, I used the top/first product which worked for a faulty head gasket. It may not work for structural failures in the casting though.

You still need to verify the cylinder head castings and compare it with those known to be manufactured with defects. Some have said the identification marks are located underneath the ignition coils, which would have to be removed... Nothing but a few bolts. But you should be researching & investigating this immediately. Very important for further diagnosis.

If you are losing coolant per fill level, and finding evidence of coolant in the engine sump, verifying the ID of cylinder heads and their manufacture could ultimately determine the diagnosis. It's not 100% but this is the direction I would take, personally. It doesn't cost anything to surf the web for info. If you find the cylinder heads to match that of the bad batch, you can then source a set of used pieces for $100-$200, have them rebuilt to new specs -$200, and install them yourself with new gaskets, water pump & thermostat. This is all hypothetical assuming there is a problem with the orig C/Hs

I am giving this info because this series truck does not have a known problem of gasket failure @ cylinder head. However, there is evidence that a series of faulty cyl heads was produced so if you have cyl heads matching info available, it is more likely your prob lies with the cyl head casting itself, not the gaskets.


thanks,
in a week the coolant is still ok, check every morning
 

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