Head Gasket Repair – This Works!

I get so many emails each day and the majority of them involve head gasket leak problems. Now, before you just run out and use the sealer I am going to suggest to you below in my video I want you to MAKE DARN SURE YOU HAVE A HEAD GASKET LEAK FIRST

I would bet that over 50% of the people I talk to that have been told they have a blown head gasket actually do not. Their mechanic has not done a proper “cooling system pressure test” which should be FIRST, so they just assume the worst and blame it on the gasket.

Not a bad gig actually, a typical head gasket repair can cost $1000 minimum. So during the repair the mechanic will most likely stumble upon the original problem and repair it but it has cost you $1000 in the process.

I made this video which hopefully will help you determine if your problem is internal inside the engine or external like a water pump leak. After you watch the video below and you still think you have an headgasket leak, then try my suggested sealer I talk about. I will put my instructions below the video for you.

Ok, so hopefully you watched my video above and you are sure you have an internal coolant leak in the engine. If so, then try this yourself and see if it helps.

Buy a can of K&W Engine Block Sealer additive (Nanotechnology is the new version and works just as well)

1. You must drain out all coolant from the radiator first
2. Take a bucket and mix the sealer and tap water together
3. Add the contents to the radiator and top off with tap water only
4. Drive the vehicle for 500 miles, not at one time but soon
5. Drain out the sealer and go back with the coolant water mix

The repair, if it can find the torn area of the gasket should be permanent.

You will not have any protection from freezing or boil over during the 500 miles, so make sure you protect your engine.

I also do not remove the spark plugs or thermostat as the can suggests. That is all there is to it and we have been using it that way for many years with a 80% success rate or so.

Watch this video to learn about engine overheating and how you can determine the problems yourself.

Please share and like on Facebook, and leave your comments below.

Austin Davis

Posted in: Coolant Leak

About the Author:

Austin Davis, consumer car repair advocate. "Hi there! I love to help people solve their car repair problems and I hope my site was helpful to you today. Thank you for stopping by."
  • Nell Ervin

    Hello Mr. Davis I really find your videos to be helpful so first thank you.Now for my issue I have a 2007 Chevy Equinox and it was overheating so we changed the thermostat and that didn’t stop the overheating so the mechanic said that it was the water pump. Changed that and it still didn’t help so we changed the temp. sensor still overheating but less often. Took it to the shop and they said it was not the heads and that it needed a pressure flush did that and it was not over heating for a week. It started to over heat while idling or low speeds so now I’m not sure what else to do we don’t have any antifreeze leaks and there is not white smoke from the tailpipe either but once it cools off a little and you take the over flow cap off ( no radiator cap) you can drive it back home without it overheating. What are your thoughts if any this is our only car thanks for your help in advance.

  • Greg Paarman

    First of all I kindly thank you for taking the time & effort to help others with what you are doing here. I have no doubt it has helped many out with a back to the wall problem. I like installing a Prestone or Peak cooling system back flush system first (cost around $5-6 dollars and is installed in the heater inlet hose) so I can clean the cooling system out extensively. I think the flush works far best with the car running. Once the water is well past crystal clear (perhaps 10 15 minutes runtime & ideally with thermostat removed) shut off the water off, let the car cool down I add a cooling system cleaner like Prestone or anything of quality. I then if able let it stay in there and try and put some miles on the car or let it run for a half hour and cool many times over (I know for some cleaning to this extent from head gasket problems will not be possible, to them I would say just clean it as best you can given your circumstances). I then back flush things yet again and cool down. This is when I typically add a head gasket sealant. Right now I am sitting in front of 2 bottles of head gasket repair… Blue Devil and K&W. After the flush I went to the auto parts store to get a repair sealant (planned on Blue Devil) and saw the K&W. What the heck, I came home with both. I decided to figure out which one to use once I got home and could read up some more. My question is given this thermostat is already pulled and out you would still recommend re-installing it prior to using the K&W? From your replies to others I see you appear to be pretty stead fast on that? My thoughts are this… if your wanting the thermostat in during that 500 miles that is probably because your wanting the vehicle to achieve the higher temperatures that having the thermostat in place gives you? Probably that extra temperature related pressure to help drive it as deep (thru &thru) into the defect as possible? If you feel having the thermostat out during the 500 mile period may have a increased chance of a less than desirable result or compromise things I would certainly re-install the new thermostat I purchased first. Any insight here so we all can understand the repair better is much appreciated. I think you did a excellent job to begin with by the way. The ONLY reason I asked this is because my thermostat was already out when I came across your website or I would not have asked. Hmmm, also wonder if anyone has done any research in adding some kind of etching liquid like vinegar or ??? to the cooling system? Doing something like this and flushing it prior to application may prove to help the stick, hold and setup value of this repair? Perhaps research into this by someone out there has some merit for a really rugged long haul repair? Next time I have a head gasket issue or I know someone with one unwilling to pay for head gasket replacement I may try this method to see how well of a repair comes of it. If this were to ever be done I know of a good non-foaming toilet bowl cleaner I would use because I unless a very strong, concentration of vinegar is used any thing else used will probably haft to be much stronger because of how much it will be diluted down. Just figure out at what point it begins to etch and not go much past that mixture ratio of cleaner / water. I have had good luck in etching things like alloy wheels and such after cleaning them / sanding them prior to their painting. Makes the paint stick really good and for the long haul where it normally would not want to stick aggressively. Just food for thought in increasing the odds to their maximum for favorable results. Thanks once again for trying to help others with your postings, it is highly appreciated!!! Greg P.

  • cw

    i see different color cans of k&w….. i purchased a 10.00 can is this the can your shop uses? orange can with yellow writing…..CRC product thanks

  • Clyde Yamasaki

    My 2004 Jeep Grand Cherokee Special Edition 4.7L V8 just started overheating. When it started doing it the the check gauges light and audible indicator came on and the gauge was maxed out so I quickly pulled over into a parking stall at a business area. I popped the hood and checked under the engine area and coolant was leaking below the crank shaft pulley. I let it cool down and added water then drove it home and it didn’t get hot. The next day I stared it up to check were the leak was and it was the water pump. I replaced the water pump and flushed out the system by removing the upper radiator hose and ran water with a water hose in the radiator and started up the car for awhile to let the water pump pump out everything in the engine. Then I replaced the radiator cap and gutted out the thermostat so that water would constantly be flowing throughout the engine and radiator. It ran fine for 2 days then I noticed that the temperature started climbing above half then to 3/4 to Hot. I checked if the radiator fan was running and it kicked on at 3/4 to Hot. It’s a Hydraulic fan driven by power steering fluid. It spins slowly as soon as you start up the car and gradually spins fast according to how much voltage the PCM applies to the radiator fan solenoid to let more or less fluid flow. I then bypassed the solenoid by wiring it directly to ground and a relay to turn it on with the ignition. It spun at max speed when I started up the car and turned off when I turned off the car. This morning when I went to work it only got just below 1/4 from cold. This afternoon when I came home from work and let the car idle, I noticed the gauge climb slowly up to past 3/4 to HOT then revved up the engine to let more coolant flow and held it for awhile and slowly saw the gauge go back down to below half. I was thinking that maybe the radiator is bad and need to be replace or a head gasket is bad. Also I think that the heater core may be plugged because when I turn up the temperature to hot on the cluster and the fan speed to max for over 1 hour it blows cold like A/C. I was thinking of removing both inlet and outlet of the heater hoses from where it connects to at the timing cover and blast the water hose at max to see if the gunk or whatever is plugging it would come out through the other end and also blast water in the timing cover where the hoses connect to. I’m not sure if the water jackets in the engine are plugged also. I don’t know how to unclog it if they are plugged. I never ran into this kind of problems before and I graduated from AMT at Hawaii Community College back in 2000 and have been working in the automotive and mechanical field working on small equipment, construction equipment, power tools, heavy equipment, cars, trucks, bulldozers, excavators, etc. I’m pretty much stumped here. I’m going to try and buy a new radiator and try to see if i can unclog the heater core with water from the water faucet then do what a mechanic friend of mine from the ARMY told me that they did with all of their military vehicles to flush out all of the gunk out of the cooling system ( USE A CAP FULL OF PINESOL CLEANING DETERGENT ). I hope this will solve my problem or I’ll buy the K&W permanent head gasket repair and try it. If i can’t unclog the heater core it will clog it up more though but that’s okay because it doesn’t get cold here in Hawaii anyway as long as it repairs the head gasket leak if there is one I’ll be happy.

  • mike

    That makes sense. I guess you’d have to make sure the rad and heater core are unclogged before attempting this. Thanks for the clarification.

  • Product works great, if you have any restriction in the radiator or heater core it will make it worse…BUT, that was probably the cause of the overheating and the head gasket failure to begin with.

    No restrictions, no problems.

  • mike

    Hi there,
    I just bought the K&W Fiberlock nanotechnolgy sealer. But I’m unsure if I should use it, I’ve read a review on Amazon UK for this product and the guy says it not only fixed the leak, but created gunk in all places and led to other problems. I don’t mind throwing away a couple of dollars to try this product, but I’d like to avoid any gunk formation in the cooling system that might lead to more severe overheating. Could you tell us about this issue of gunk formation following the use of this sealant, how likely is it to happen, how severe it might be, and is there a way to avoid it? Thanks for creating these videos by the way.

  • Austin Davis

    It does sound possible, but get the cooling system pressure test first before you jump to conclusions and use the sealer. Once you are sure, try the sealer.

  • Kay H.

    Thanks for the video. My car (95 Mercury Villager) needs coolant every 3 days. I noticed a white foam under the oil cap, and once, had milky residue on my oil dipstick, but it comes and goes. The white smoke from the exhaust smells like gas when I start the car. My temp gage sits in the center (a recent problem). The temp has been ok till a week ago. The gage starts to rise as soon as I start the car. Do you think I have a blown gasket?

  • Austin Davis

    Well, anytime I hear people tell me “over heats only in traffic” or “temp gauge goes down when I turn on the heater or the car starts moving faster” the first thing that comes to mind is low coolant levels in the system or an air pocket trapped inside the system that needs to be bled out.

    First thing I would do if you were in my shop, get a cooling system pressure test to see if you have a coolant leak. Second thing, make sure the system is holding pressure…upper radiator hose should be hard to squeeze together when the engine is warm.

    Third thing, double check electric radiator fan operation and make sure there is no obstruction of air flow across the radiator. Fourth, check thermostat operation, and make sure the proper temperature thermostat was installed.

    When you run the heater…the heater core (small radiator inside the dashboard) is removing the excess heat from the engine that the radiator is unable to do.

  • Kevin

    When stating ‘Car overheats in heavy traffic’, I mean the moment it goes past half. Then I switch on the fan (moving the heater knob to full heat sometimes, othertimes I leave the heater knob at full cold), watch the heat gauge needle. Once out of heavy traffic and heat gauge below half, I switch the fan off.

  • Kevin

    One evening when raining i used the heater to demist the windscreen (car does not have aircon). After using heater for a while (30 minutes) the heat gauge went just past half mark. I was puzzled since this never happened before, decided to switch heater off.

    2 weeks later going to work in the morming, the car overheated (gauge went to 3/4 – switched car off), mechanic said it was due to thermostat stuck in closed position. Cylinder head skimmed, head gasket replaced.

    Car overheats in heavy traffic. Had radiator and radiator cap replaced. No water hose or water pump leaks. Occasional leak from reservoir overflow pipe (when car is in stationary position). Electric cooling fan is working as expected. Some mechanics say car runs too cool, if light traffic gauge around 1/4 (maybe thermostat is occasionally staying open).

    Car still overheats in heavy traffic (if I use the heater the temperature drops quickly to 1/4, some days I use the fan without moving the heater knob the full heat – so heater knob at full cold, the temperature also drops quickly to 1/4). The block test was not very convincing, the blue liquid had a feint tint of green (not just green only). There is nothing wrong with car performance.

  • Austin Davis

    I would try hard to get my money back and get something else….Toyota, Honda, Hyundai or Kia. If they don’t, then get a mechanic to pressure test the cooling system for leaks, check the radiator for a restriction and check the electric radiator cooling fan motor before adding the sealer. The damaged head gasket is the symptom not the cause of overheating, you have to find and repair the source of the overheating or it will keep happening.

  • Austin Davis

    No, and the K&W sealer I talk about is the best on the market.

  • sue

    My 95 caddy eldorado seems to have blown a head gasket..It has 54000 miles on it looks like brand new…I have rough start then as it levels out the white smoke just fogs out of both exhaust pipel…The temperture got up to 236 while idoling
    I have been told its a head gasket..but it doesnt smoke white smoke all the time So is it a head gasket or what I bought this 14 days ago and have only put 34 miles on the car …Im hoping the car lot will give me my money back or fix the car.
    What do you think

  • sam mitchell

    Any chance you know of a sealer for the head gasket that works with dex-cool, or long life anti-freeze? I would appreciate any help you could give.

  • Austin Davis

    Unfortunately it will not, it is a cooling system sealer for coolant/antifreeze leaks. I am afraid you will have to replace the gasket, I have not found a “sealer” that will work in this situation. If you have a timing belt, I would replace it at the same time because oil is/has been leaking on it and will weaken the rubber. Thanks for your comment.

  • Ray

    I have a leaking timing cover gasket. My mechanic recommended using Bars head gasket sealer, it worked for 6 months, but now I’m seeing a small leak from the same spot on the timing cover. Will K&W block sealer work on timing cover gaskets too?
    Great videos BTW. Your “simplified” explanations makes it easy for the layman to understand. Thanks!

  • I have a Volvo v40 that seemed to suddenly jump into the red zone, so had it towed to a Volvo dealer/repair shop. They said there was hydrocarbons in the coolant. So, thinking major repair at over $2K, had it towed home. It goes into the red zone very quickly even after a few blocks and I have to add water. Oil still looks good on dip stick. The thermostat (we did replace it and that of course wasn’t the problem) hose is opposite the one on your truck picture. The point being, the large hose on my cars right side coming off the radiator, I believe, is cool while the one on the thermostat side is hot. The leak on the car comes on the right side (facing the car front) while the place where water/coolant is added is on the left.
    One guy offered to repair what he thinks is a head gasket leak for $1500 to $2000 but that depends on the cost of the head gasket, which he quoted at $150 on up. Thus, I went online and looked up the auto parts and found it was only $45.

    Now, of course, I’m suspicious and wanting more info. I don’t trust any of these mechanics and wonder if you think it sounds like the H&W would work. In other words, what kind of a problem might it be. If a can of stop leak will work and save me using my credit card, I’m all for it.

  • Austin Davis

    The newer version nano, says it works with coolant. I am an old school kinda guy and still use the older hard can version and drain out all coolant. I have gotten a lot of emails from visitors stating the newer version worked well with coolant, so I will let you decide which way to go. Keep us posted as to your results.

  • Alan

    I’m going to go out and buy the Nanotechnology kind do you still need to drain and add water, or can you use the fluid that is in there while still adding a bucket of water k&w mix

  • Austin Davis

    I do not let it dry out, just refill with 50/50 and keep your fingers and toes crossed. Thanks for your update.

  • Rob Mitchell

    Hello again! So far so good. Just one more question. When you flush the sealer out of the cooling system, is it necessary to allow the cooling system to dry for a day as the k&w instructions specify or can you just immediately refill with 50/50 and keep driving? The sealer seems to have worked thanks again!

  • Austin Davis

    I would get a second opinion from another mechanic, preferably at the BWM dealership. You might have air in the system that needs to be bled out? These cars are much different than a Chevy, so make sure your get a qualified BMW mechanic who knows these cars. You have not mentioned any of the common symptoms of a head gasket leak….but if you have ruled everything else out and want to try the sealer, it won’t hurt anything but treat it as a last resort option.

  • richard charles

    i have an 2001 bmw 325i 4 door that my mechanic says has a head gasket leak , I change radiator , all hoses , thermostat , water pump, fan clutch , expansion vavle . no leaks noted , but builds up to much pressure and start to overheat .They have did a presssure ck that’s how i know , thank .

  • Austin Davis

    Gasoline engines don’t like to idle for long periods of time, so try not to do that. Would be better to use a drop light under the hood, remove the radiator cap to allow for expansion and in the morning put another 100 miles on it, then drain and flush out the sealer if you feel it has repaired the leak.

  • Austin Davis

    A 100 Watt drop light under the hood, and remove the radiator cap for room for expansion will probably be enough, but parking in a garage would be nice as well.

  • Rob Mitchell

    Just ran to town and no white smoke. I also did not notice any water dripping from the exhaust which was also happening before the sealer was used. I think it may have worked. I’ll keep you posted. What about freeze protection for tonight. Can I just idle it every couple of hours or maybe just let it run all night? I guess I could run to the store and get a drop light and extention cord if necessary. Thanks for the input!

  • Rob Mitchell

    No I didn’t get the system pressure tested. My temp gauge was broken when I got the truck and I suspect it had been overheated either before I got it or shortly after. I found and fixed an external coolant leak a few weeks ago. The coolant level continued to drop after fixing that and replacing a stuck thermostat. The truck hasn’t been overheating but there has been a lot of white smoke and coolant vanishing with no noticeable cause so I figured it must be the head gasket. I flushed the coolant and followed your instructions for the nanotech sealer. I did notice after driving about 40 miles, there was no more white smoke while idling. I’m hoping that and the fact that the coolant level appears to be holding means the sealer found its mark and worked. I put almost a hundred miles on it today. Temps will be cold tonight (29 or so) which is one reason I may just want to let it idle all night. I kept it from freezing last night by starting it every 2 hours during break at work but I am not working tonight and I wonder if idling for 6-8 hours will hurt anything? It has not overheated even with the high stress highway driving today so I don’t think I have to worry about boil out. What do you think?

  • Austin Davis

    Did you get a cooling system pressure test first to make sure there are no external leaks, and an internal leak is present? If you got lots of white smoke and losing coolant, engine running hot, check engine light on or engine missing/running rough then chances are an internal leak is present.

    In my experience it can take up to 500 miles for the repair to take hold and become permanent but the majority of the time within a few miles of driving (less than 50) the repair has taken place. It can take a while for the coolant/water to burn out of the exhaust system. I would pack a lunch, take a few gallons of water and hit the highway for a good 1 hour non stop drive.

    Keep an eye on the temp gauge and do not let the engine overheat, pull over let cool down and top off with water if it does. Turn the heater on high for a few minutes too to let the mixture circulate through the system.

  • Rob Mitchell


    Just a couple of questions about the sealer. Can I just idle the vehicle and get the same result or is driving the mileage a must? Also, How long does it normally take to get rid of the white smoke from the exhaust with the sealer? I have driven over 40 miles and still see loads of white smoke while idling. I did notice that the water level seems to be holding better though. Is there anything else that could cause white smoke besides a blown head gasket? Thanks!

  • Austin Davis

    Thank you Kenneth

  • kenneth russell

    Thanks for all the info,you seem very knowledgeable about automotive issues!

  • Austin Davis

    Awesome Jenny, glad to be of assistance, let me know if you need anything from me.

  • Jenny

    Hi, the video was a great help, I must admit that I didn’t do it myself, but after watching the video I took my car to the shop and they started saying that a lot of other thing were wrong and they tried to charge me a lot, when I started quoting you they were surprised and realized I knew what I was talking about and got it repaired for a lot less than they were wanting to charge me, thanks!

  • Austin Davis

    Keep us posted as to the outcome. Have a great week

  • Jose Apostol

    I have the answer from your video. Thank you sir.

  • Jose Apostol

    Thank you for the instruction. Should I remove the thermostat before I use the K&W block sealer?