After the dealer's mechanic said that I had a "blown" head gasket when I asked why I had a repeat trouble codes P0301-P0303-P0305 after their fixing those codes a couple of months ago (though my car does not overheat does not have white smoke from exhaust pipes nor bubbles in coolant, and blown head alike symptoms), I bought a bottle of Bar's Leaks Block seal Head Gasket Fix which allegedly fixes blown head gaskets. Before using it, I must know if it will not damage any parts of the radiator --some reviews stated that they found metal fibers around the heat core or that suddenly the car could not heat anymore--. Both the manufacturer and the auto parts people told me that no, it will not. Please tell me if anyone ever used safely this type of seal/s. Thank you so much.

 

I used it on my Jeep cherokee and it worked well. However, I caught it very early. If you have been driving with the issue for a while, it may be too late.

Just follow the directions exactly. I think I used too much since its still built up around by radiator filler neck, and I had to flush it out a few times. Don't pour the whole bottle if you don't need to.

You may need to change the oil also if its been contaminated with coolant.

I also had my heater core disconnected and bypassed for this. You may want to consider doing that if you're concerned about the core getting clogged up - at least for a few days while its still warm outside.

 

Thank you gkubrak for cautioning me about for how long I should not have had this issue. My problem with Jaguar mechanics is that I DID NOT HAVE THIS ISSUE AT ALL. They invented it to avoid warranty responsibility for incorrectly fixing my P0300 P0301 P0303 P0305 P1316 trouble codes complaint back in February. Thankful to THERMO's and his friend's wonderful offered help, I will work by elimination of this "issue" first to get to the real issue of those codes. My car never overheated, never had white smoke or bubbling coolant or milky oil cap, the experiment with head gasket fixing though not broken had to get the least risky approach via a non drastic head gasket sealant. Fortunately I returned the Bar's sealant and replaced it as advised with K Seal, which does not go over anything to clog them like Bar's as it is not a paste like the Bar's but a not harming conglomerate of copper and aluminum fibers, with no need to heat car and A/C before driving.Thanks you all very much.

 

I used head gasket sealers on my 1998 Cadillac Eldorado with the Northstar engine, and they did not hold for more than a 50 miles or so. A head gasket breach has to be addressed correctly, meaning, pull the top of the motor and replace the gasket. These 'save your butt' potions, rarely do much long term good.

 

There's a couple of different "methods" and numerous different materials. For decades, General Motors put AC Delco Seal Tabs (ground ginger root fibers) in new car cooling systems at the factory as a preventative to stop any tiny drips from resulting in a warranty claim before the 12 months were up. By the 1990s, the machining quality was up to the point that they didn't need to do that anymore. But it wasn't a lot, like a teaspoon in a 3 gallon system. You'd never know it was in there. If there was a tiny leak, the little fibers would slowly find it and build up to block it......maybe. The problems with these occur because people think if a little will fix it in a couple of weeks, a LOT will fix it in a few minutes and they clog up the works. I can't see how any of those that rely on fibers or crystals or copper filings or any other solids would ever fix a "blown" headgasket tho. A tiny leak, yes, but surely they wouldn't do anything for a "blown" headgasket. If you have cylinder pressure blowing back into the cooling system, I would think that would also blow any blocking agents back out of whatever hole there is like backflushing a filter.

Now for a blown headgasket, a possibility, could be the brands that rely on sodium metasilicate. From a chemistry class standpoint, its fascinating as Mr Spock might say. Its commonly known as "water glass" because it dissolves in water but can be turned into a silica xerogel by heating (which is actually not very gel-like, but rather quite hard like glass). The way it works, is that as the solution is being force out the hole under pressure, the water is boiling away, leaving the hot sodium metasilicate behind. That's where it gets interesting. Sodium metasilicate melts at 212-221 degrees F, but it only melts once. After it cools and hardens, it won't melt again unless you get it to nearly 1,500 degrees F. Of course it won't seal a blown headgasket while its running, but rather after you shut the engine off, the pressure in the cooling system blows the solution out the hole (back into the cylinder presumably) and as the water boils away, it fills the hole with silica xerogel, essentially the same stuff that's in those little bags of dessicant.

But its not something you want to leave in your cooling system. The instructions tell you to flush all the antifreeze out first (it can compromise the solidity of the resulting repair), fill it with distilled water and sodium metasilicate solution, run the engine at operating temperature for like an hour, let it cool completely, and finally flush all the solution out of the system before refilling with antifreeze. But here is where this stuff gets dangerous. Its stable as long as it stays dissolved in water, but disastrous if your engine happens to boil over during the treatment. If you car is actually overheating and boils, then the stuff can turn to xerogel inside the cooling system passages and then you have little glass beads circulating that you'll never completely flush out. Also, if the hole in the compression ring is too big for the solution to seal, then you have this glass-making solution pouring inside the cylinder, or worse, if its pouring into one of the oil passages. The only way I would try it is if a car were running perfectly but maybe just dripping on the ground somewhere (that was harder to get to for repair than the value of the car) or loosing a small amount of coolant over time and not clear where.

 

THANK YOU ALL SO VERY MUCH for your precious very informative replies. After I poured not Bar's but K Seal Ultimate* I had no problems including engine light for about 270 miles trips, one of 150 and other four 30 miles each. Either I had a very small puncture in the gasket that the K Seal fixed or my P0300-P0301-P0303-P0305 had another cause than a coolant leak (thank you, Thermo for suggestion). As said, my engine oil is clear, my car does not overheat, my coolant level is untouched and not bubbling, nor is my exhaust blowing white smoke. I am watching my next trips after these quiet 270 miles, with, of course, crossed fingers.
____________________
K Seal being produced by Brighton University researchers in UK

 

Marcela, give Mona a few belly rubs and you should be good to go. I know you feel like the shoe is about to drop but from what I have heard, you should be good to go for a long, long time. Keep an eye on things, but also relax and enjoy life.

 

Your technological attention to my humble x-type kitchen spices ignorance makes as always our day sunny. Though I don't see you I know that you are always around (hey, Mona's CEL, beware of him!). Thank you, Sir.

 

Hi Patterson,

I am trying to send you a message regarding your knock sensor replacement on your X Type.

I added you as a friend as I am unsure how to send you a message? Anyway was just wondering if your new position you made for your knock sensor worked out all ok? I am wanting to do this on mine and came across your post from 2018 and wanted to see how you went with it?

If you could get back to me I would much appreciative


Thanks

 

thats a great explanation of what it is, what it does and how it works! Thanks!

 

Do not use any leak seal or leak block in you Jag. engine; the coolant will gum up and you will get blow engine; if you lost coolant but don't see it on the floor, it blow the head gaskets,drain the oil you'll see the coolant mixed with the oil; only way to fix it is to replace the heads gaskets, if you can DY it doesn't cost much, but time consuming. if you let the garage do it prepare to open your wallet, and still have to leave it in the garage for a few weeks.