"Stop Leak" products any good?

Honda Experts,
Has anyone ever tried one of the "stop leak" products? Did it work for you? I'm considering trying one of them.
I have a very small water leak. I think it's in the head gasket. It's
so small, I only have to add anti-freeze about every 1,000 miles. But the check engine light comes on sometimes.
Bar's Leaks has "Head Gasket Fix" for $30 Says: This formulation contains a combination of antifreeze compatible sodium silicate sealing liquid and various size gasket sealing particles which penetrate gaps & cracks and harden to permanently stop leaks.
CRC Industries also has a product "Permanent Head Gasket & Block Repair with Nanotechnology" for $21. Says: Permanent repair for head gaskets, radiator and heater core leaks. Advanced nanoparticles allow product to fill voids that a typical head gasket repair product can't
Do you know if these work? Even if temporarily? Do you know if they also do bad things to my car? It's a 97 Civic LX, with 260,000 miles.
Note: I notice that some versions of these say they don't work with coolant, which seems kinda worthless. I would get the kind that does work with anti-freeze.
Thank you,
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There are no experts in here. The real experts are employed by someone else to work on cars for pay. What you have in here are a bunch of home grease- monkeys dispensing what they consider to be their best guesses and most sagacious ignorance.
I'm not a pro either, so take my advice with that in mind.

Go ahead. It might work for a short time. Maybe. Or maybe not. And it /will/ cause a headache for the professional whose job it will eventually be to fix the problem properly.
--
Tegger

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Somewhere on teh intarwebs Tegger wrote:

Heh! I remember the days when the 'nanoparticles' we used for tiny leaks was half a pot of pre-ground white pepper. That was only on engines that were either old or non-critical with a leak that was at the annoyance end of the scale rather than the dangerous end.
The theory being that the various sizes or pepper grinds would stay in suspension and block the leak. The bigger ones first, then smaller ones as the gaps got smaller and the water-pressure would force them tighter as they would have absorbed water and be 'pliable', until the leak was blocked. At least that's what the old mechanic (my uncle) told me. <g>
--
Shaun.

"Humans will have advanced a long, long, way when religious belief has a
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On 03/06/2012 11:09 AM, Bill wrote:

some of them definitely work. for a while. back in the bad old days, that stuff was put into the coolant at the factory. jaguar for example.

what is the code? how do you know it's related?

yes they do, temporarily it's just a solution of this stuff: <http://en.wikipedia.org/wiki/Sodium_silicate with maybe some fine sand particles in suspension.

they can be a real pita to clean off if you later have to have the head done properly.

the stuff that works with anti-freeze is less long lasting. the stuff that "doesn't work with coolant" works fine with water, so you just drain and fill with that a couple of times before adding. follow the instructions on the container exactly.

in some respects, what you're contemplating is a better solution than getting the head done at a shop and having it ruined thusly:
http://www.flickr.com/photos/38636024@N00/6904448039
shops always skim heads. because it's traditional and because no one asks questions. it's like religious dogma vs. heliocentricity. reality is out there for anyone who dare think and observe.
--
nomina rutrum rutrum

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...
Isn't this pretty much the same gunk they poured in the fuel line (or was it into the oil system?) to destroy the engines on the cash-for-clunkers program?
J.
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wrote:

http://www.cashforclunkersfacts.com/car-dealers/engine-destruction /
On Friday July 24, 2009 the NHTSA published their Final Rule document which outlines a number of new ideas surrounding the Cash for Clunker bill and the Car Allowance Rebate System (CARS).
One of the of the most interesting items was the detail in which the NHTSA describes how dealers have to kill the engine of the clunker being traded in. This is the first time dealers were told that they would have to drain a few quarts of oil from each clunker and inject a Sodium Silicate solution which would render the engine inoperable.
Introducing the role of Doctor Death
Here is the wording from the NHTSA Final Rule document:
The agency has determined that a quick, inexpensive, and environmentally safe process exists to disable the engine of the trade-in vehicle while in the dealers possession. Removing the engine oil from the crankcase, replacing it with a 40 percent solution of sodium silicate (a substance used in similar concentrations in many common vehicle applications, including patching mufflers and radiators), and running the engine for a short period of time at low speeds renders the engine inoperable.
Generally, this will require just two quarts of the sodium silicate solution. The retail price for two quarts of this solution (enough to disable the largest engine under the program) is under $7, and the time involved should not substantially exceed that of a typical oil change.
The agency has tested this method at its Vehicle Research and Test Center and found it safe, quick, and effective ...
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On 03/12/2012 04:43 PM, JRStern wrote:

yup, sounds like it. note the price vs. the "secret gasket fix solution" price. much like bromthymol blue vs. "head gasket leak detector fluid".
--
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If you have a small water leak in the head gasket, you have the potential of introducing that crap into the cylinder. Now water is a pretty bad thing but add this crap and you might be scrapping the engine.
"nano" seems to have become a popular word for "the same old junk with a new name".
I'd recommend a trip to your dealer. A new head gasket might seem expensive, but only until you buy a new engine.
When was the last time you changed your belts? If you're willing to go this cheep and long on a "minor" leak, you probably need to get new belts, too. Which should happen when you get a new gasket.
Here's an idea. Start the engine and let it warm up for about 5 minutes. Drive over to a clean, dry area. Put some newspaper, cardboard, silk sheets under the engine and let it idle for a couple more minutes. Look under the car. If there's no water on the sheets (or whatever) then turn the engine off and wait a couple more. Water" New water pump.
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