BlueDevil Products 38386 Head Gasket Sealer - 1 Quart

Here's the scenario: 2003 Nissan Altima 2.5 liter, 175K miles on it. Symptoms: Losing coolant, about 8oz a day, but no external leaks. Had a problem with heat going back to last winter - there is no heat when the engine is at idle, the engine has to be around 2K revolutions or higher to get heat from the heater core. This is because there is combustion gas constantly leaking into the coolant system creating a vapor lock in the heater core. Engine has occasional misfires in cylinder 3, I believe caused by coolant leaking into that cylinder. If the radiator is running under pressure the engine sputters and struggles to run at times - I believe because an over-pressurized coolant system is forcing some coolant into the engine. Setting the radiator cap so the radiator doesn't pressurize, the engine runs fine. Replaced both thermostats (yes there are two for some reason) and made no difference. Given those circumstances I was very certain there was a head gasket issue. Because of the high mileage I didn't want the expense of doing a head job, so decided to give Blue Devil a try. I followed the instructions on the bottle to the letter with these exceptions: (1). Idled the engine with the Blue Devil mixture in it for 80 minutes, not 50 as the instructions state. After letting the engine cool overnight and starting it, it was rough getting it going and it sputtered a bit at first. This led me to believe that the mixture may have bled into a cylinder while under pressure and the car not running. So: (2). I drove the car for 3 days, about 200 miles, with the mixture still in radiator and thermostats out, to give the pure mixture more time to seal any leaks. (3). After 3 days driving I drained the coolant down, keeping the liquid, put the thermostats back in, then added enough anti-freeze for a 50/50 mix. Topped up with the Blue Devil/water mix and bled air out of the system.. It's now been over 2 weeks since I used the Blue Devil, I've driven about 1500 miles including a day trip of around 400 miles. Engine runs great, there are no misfires, no loss of coolant, no excess pressure and there is ample heat from the heater core with the car at idle. So at this point, problem is 100% fixed. Blue Devil did the job as advertised and I'm a happy customer so far. This is supposed to be a permanent repair so real proof will be how it holds up over time, including the upcoming winter. I'm hoping to get 2 to 3 more years from the car, until the car I just purchased for my wife is paid off and I can afford to replace this one. I will update this review as time passes so keep tuned, but so far, so good! **UPDATE** - October 3 2016, going on 2 months and over 4K miles driving after using the product. Car continues to run great, no indications of any head gasket issues. I've driven the car on 2 trips, one 350 miles and one 750 miles at speeds up to 80mph. No problems and am getting better gas mileage on the trips than ever, 31 to 32 mpg highway. **UPDATE 2** - January 5, 2017 - it's now been 10K miles since using the product. Still no issues at all, no coolant leaks or loss, no air or combustion gasses getting into the coolant system. Prior to the Blue Devil repair, air/combustion gas would be trapped in the heater core meaning no heat inside the car unless RPM's were very high. Now there is no problem with heat, even at idle the heat blows strong. I'm sure results of using the Blue Devil Gasket Sealer may vary depending on the type and extent of damage to the head gasket, but in my case it has resulted in an effective and very cost-efficient repair. **UPDATE** - August 21, 2017. It's been one year, 21,500 miles and I've had no problems with the car at all. Running great, no coolant or head gasket leak. **UPDATE** - July 13, 2018. 212,000 miles on the car, 37,000 miles and 2 years since I added Blue Devil. Still no issues, not losing any coolant, car runs great. 2 years of driving this car on a 60 mile/day work commute plus personal driving miles. **UPDATE** - July 5, 2019. 233,000 miles on the car, almost 3 years and 58K miles since Blue Devil was added. A few weeks ago I noticed my coolant level was slowly dropping. No external leaks so it has to be internal. I've wrapped a paper clip around the internal radiator cap seal so no pressure builds in the cooling system, coolant level is now stable. There is no evidence of combustion gases in the coolant, however there may be issues developing, I will monitor closely. *Sep 8, 2018 - turns out a small bypass hose to the throttle body had a slow leak that dripped onto the transaxle housing and collected in a small area that evaporated before it dripped to the ground. The leak got worse and I noticed it, replaced the hose and now there's no coolant loss, so no internal leaks. Engine is still running good.

Bought my 1996 Subaru Outback Impreza new off the lot during its birthyear (96). Since then, it has taken me through a dozen or so states, two wives, two kids, two dogs, five cats, and around 75 chickens. I've hauled trailers, firewood, camped from and lived out of this vehicle (the latter being a temporary homelessness between graduate schools). I had the head gasket replaced after around 140k miles ... about 15 years ago, and over the past year she wouldn't start again after running without a 20 minute rest. I've basically rebuilt every pump, filter, belt, and other doo dads myself, but a head gasket is beyond my ken. I should also mention I coated the vehicle with two layers of black semi-gloss housepaint after 200K miles ... she's not much of a looker but has always gone forwards and backwards, all the windows still work, as well as heat and AC ... When she started overheating like mad three months ago, I took her to my local mechanic who said he could do the head gaskets for "cheap" at around $1600, if he were to do it right and machine the heads. The car is worth less than $400 on paper (the tires are literally worth more than the car), but ... it's like putting down your favorite dog. I got to shopping for a new/used Honda, drove my motorbike to work for a few weeks, and prepared myself for the worst. THEN! I stumbled across this magical fluid, which still seems too good to be true. $50 for a functional vehicle? I figured it was worth a hail-mary, and had some delivered. While waiting for its arrival, I did tons of research - the odds seemed about 50/50, but worth a Saturday afternoon given our history. I followed instructions EXACTLY, flushed the radiator, etc., pored in half the bottle, ran it for 45 minutes and prayed for the best. Next morning she got to work, but just barely - I had to run the heat full blast to keep it from blowing up, and the radiator reservoir was bubbling over like mad (not a good sign). I came home despondent and wondering what the chances were of me doing a head gasket repair in my driveway ... ran across some reddit threads, and followed some random advice that said sometimes it takes more than one application. So without even removing the thermostat, I chunked the other half of the bottle in the radiator and figured it couldn't hurt at this point. Ran it 45 more minutes and ... The next morning she made it to work without overheating at all! And over the next 3-4 days, she seemed to be running BETTER every day! Lo and behold, the thing will now crank up every time without a cooling period (I have NO idea how it fixed this issue, but don't really care). After a couple months, it started to overheat just a tad bit and didn't restart for ten minutes while running errands, so I got another bottle, dumped half into the radiator, and ... viola! Hell, even if I have to toss a bottle in there every three months or so, that's $20 / month, which by my calculations is much cheaper than a car payment, and I get to keep my OldBaru :) I ended up buying a 2023 Honda CRV for highway / roadtripping, but purchased a cover for it & it sits under wraps in the driveway for 2-3 weeks at a time, as I keep the miles off it by rolling in the Subie whenever possible. Thusfar, I've had her on the road for up to 90 minutes with no problems, but I'm wary of taking her out for much longer, and don't need to anyway with the Honda in reserve. Long / short - this stuff actually works, but you may have to tweak the directions / application a little bit. It's a win-win if, like me, it's either the magic fluid or the scrapyard :) Good Luck!

I bought this product summer of 2014 when my 2004 Toyota Matrix XR (1zzge) engine developed a head gasket problem (burning coolant [exhaust moisture + sweet smell], but no coolant in oil or oil in coolant). I had a few minor overheats due to a cracked radiator. but this engine has a weak head prone to warpage. I had recently had this engine rebuilt and could not afford to do it again. I was getting by for a month by refilling the radiator every 10 to 20 miles, it was a slow head gasket leak. I didn't think this would work but it did. I have put 20k miles on the car and its holding strong, I have even used the Matrix last week to Tow a 2,400 LB BMW with no issues. So here's how I used it; I took out the thermostat, but left the rubber gasket and reinstalled the housing (it is a pain in the butt on my car, but it worked). I emptied all the coolant and flushed it with water. I read online the red devil can react with coolant so we have to clean out the system. I bought peak cooling system flush and mixed it with straight water per the instructions and bleed the cooling system, Do yourself a favor and get the "Lisle 24680 Spill-Free Funnel", I was broke and spent part of that weeks food money on it, but so worth it! It really is spill free, and spills are the last thing you want when the blue devil is about $50 a bottle. After getting the air bubbles out I took it on the highway for 10 min to let the engine heat up and let the cleaner do its thing. I then flushed it with water about 3 times to get all of that cleaner out of the system, I was shocked at how dirty the water that came out was, These cooling systems need flushing. Next I drained the system and put the plug in, I added some distilled water (1/4 gallon) then I used about half of the blue devil. I continued filling the system till it wouldn't take any more. From there I started the car I topped the system up as needed. Once I had enough water in the car (i checked the capacity of my system online), I put the radiator cap back on to build pressure and reach operating temperature. I ran the car for an hour or hour and a half, what ever the blue devil instructions said. I noticed the exhaust vapor had stopped, I needed to get to work that afternoon so I gave myself extra time and baby-ied it all the way there. I took it real easy the first month, still carrying about 6 galons of water at any given time. Two months later I nearly had a breakdown when I lent it to a friend while I was over seas and he said it refused to start the day before I got back. It was just the starter : ) . I know its difficult to believe a sealer can repair a leaking head gasket, but It worked for me, If I can get 4 more years out of this car I'll be happy, It it starts leaking again ill just use red devil again. On a side note red devil is not made for all cases, that BMW I was towing had blown a gasket too, I was tempted to use the product! But I knew that the leak on the BMW was much worse with pooling coolant in some cylinders. For a larger leak like that I would not want to rely on a sealer for another family member's daily driver, yes it could have worked, but BMW's are a little more delicate (temperamental), and I don't mind doing a head gasket on the BMW since that car has less than 100k and will retain its value better than our beat up matrix. In 2018 I sold the matrix, It still ran but after towing an suv started smoking again. The blue devil got me the time I needed out of that car, several more years till I could gain some traction on a career; for me it eventually let go. I was however pushing the car beyond the manufacturer recommendations, so I can’t blame the blue devil product. If you have the money it’s no substitute for the actual head gasket. If you don’t it’s a good bandaid till you can pay for the fix or replace the car.

Used on 2006 Toyota Avalon, 131k miles. This vehicle had been poorly maintained and had a host of issues before it started overheating and I picked it up cheap. Periodic misfire, some o2 sensor/cat converter codes, then it started overheating with exhaust gas in coolant. It didn't seem to be burning any (or much) coolant, and there was no coolant-oil mixing and no external leaks. But exhaust gas was pushing into the coolant causing rapid overheating and overpressurization and blowing steam out the coolant reservoir tank. I chose Blue Devil because it has no fibers...only active ingredient is the sodium silicate AKA liquid glass. I had already replaced water pump and thermostat and put in new OEM coolant. I added the Blue Devil with thermostat installed. Most people tell you to remove that, but the instructions on the bottle don't mention it, and my understanding is that the sodium silicate is unlikely to clog the thermostat—you remove it mainly to get the Blue Devil moving through the whole system while the car is still heating up, so it can work right away. With Blue Devil in and rad cap on, I let it idle for about an hour. During this time I was monitoring the coolant temp on my scan tool and it was running hot, 210-215, but not out of control like the 250+ it would otherwise do. After that hour I took it for a short drive, and the temp started running away to 250+. Came home, parked, turned off, and let it sit overnight. The next morning I drove it and the temp zeroed in at ~190 and stayed there. Success! I have NOT changed the coolant since then. The thermostat was still in and hadn't clogged, heater core hadn't clogged, radiator cap hadn't clogged, and my reasoning was that keeping sodium silicate running through the system indefinitely was a good idea...let it keep working in case any more exhaust gases tried to push past the "repair". Later on I changed the spark plugs, and I stuck my borescope into each cylinder. I hadn't driven it in about a week. Cylinders 2, 4, and 6 looked healthy but cylinders 1 and 3 looked messed up. There were black/brown scorched areas on the cylinder walls, and worst of all there a puddle of coolant sitting on top of #1 piston. My theory is that when the engine cools off the repaired area opens up and lets some of the still-warm, still-pressurized coolant push through into the cylinder. So I think it's good that I still have the Blue Devil in the system, maybe the repair will improve over time. However, it's been a couple months, and I've had no misfires and no overheating. The coolant loss from that leak into cylinder 1 is slow. Couple considerations if you've read this far: doing a proper head repair after overheating or oil mixing or whatever is more expensive than it seems even if you DIY. You can't just replace the head gasket and put it all back together. You have to measure the block with a straightedge, measure the head with a straightedge, and get the head pressure tested at a machine shop in case there's a micro-crack in it. Most of the time, aluminum heads will be warped after overheating, and that will be the real cause of the "blown head gasket" symptoms. You might need to replace the head ($150 at a junkyard) but then you should really get that properly cleaned, machined, and rebuilt at a machine shop (another $500 or so). Really after overheating an engine, it's probably best to just replace the engine so you don't have to deal with all that...but then junkyard engines don't always work out either. All of these unknowns and the potential runaway time & costs even for DIY is why I tried Blue Devil on this car. But even though it "worked" I'm still left in a position where I would be hesitant about doing long trips, and I really should carry a spare bottle of Blue Devil and a jug of coolant in the trunk forever, and I really need to be checking the coolant reservoir and the oil dipstick every single time I fill the gas tank from now until kingdom come if I want to make the most of this "repair". Bottom line is that most people give 5 stars if Blue Devil alleviates their car's symptoms. I'm only giving 4 stars because I can see that I'm still losing some coolant, and because this kind of hack leaves with a mortgage on your future of needing to be prepared for the next time you overheat, and checking coolant/oil frequently. Still, would I use it again? You bet.

I have been working on my own cars since I was 21 about 12 years ago. I have swapped and built engines. My honest opinion is avoid this stuff like the plague. It's a temporary solution to a permanent problem. You may be the lucky one that has a small gasket leak, but you may be one of the many (just search engine the negative results and you'll find some on Youtube) that has larger problems. This stuff works as it says, the problem is when you have more than a head gasket leak and it goes into those places and chemically welds other things in place, LIKE YOUR PISTONS. I have a seized engine that will not turn over, which is no issue because I have another one to replace it (FYI, if you intend to keep an engine do not use this; this is a last resort as it could result in having to junk an engine - because it's just cheaper - as it will chemically weld on all the internal surfaces in the engine if you have more than a gasket leak). The only way to know if you have more than a head gasket leak is to pull the head off in the first place. By that time you've already gotten far enough to replace the HG, and found any other issues that need fixed anyways. If you have an HG leak you might have other issues, as I did. My application is a 4.0 I6 Jeep Cherokee engine. It has either a cracked head or cylinder wall in the 6th cylinder which is not a common malady. I thought it was just an HG leak only since I could see a visible leak. I decided to investigate mechanic-in-a-can solutions and determined BDP's HG sealer to be the best option. I now have a fully seized engine that I can't remove from the transmission because it requires turning the crank to be able to get the bolts off of the flywheel so it will come off of the torque converter (the TC turns and locks 3 separate times into the transmission, it doesn't come out until you have the engine out of the way). So you see I have a serious conundrum, especially since I am not junking that transmission with the engine since it is a brand new remanufactured transmission. BDP has opened up a serious can of worms for me beyond my wildest dreams. I will never use this or any other chemical in my coolant system to stop a leak. It's a temporary (for me it was VERY temporary) false sense of security. The leaks stopped, but one day at work I had to make some long trips after a few weeks of having it in and the entire coolant system bled out. The way the thermostats in these engines work is if you don't have any coolant it will be an extra long time before it registers the heat since it is at the very top of the engine. It's the last spot for heat to spread too. So as soon as the gauge jumped to the right and sounded an alarm I pulled over, by the damage was already done by then. UPDATE: It's later today (12-17-2017). I got the head off of it. I'm going to give you 6 guesses which cylinder Blue Devil sealed up for me but you're only going to need 1. It also plugged up 1 of my catalytic converters. Ultimately this all was the result of a not-completely-tightened head bolt in the very back of the engine (I found out as I was un-torque'ing all the bolts). It was practically loose. I didn't bother checking them when I put this engine in last year because when it came out in 2014 it was a working engine that never had any problems. I bought it from a guy in Ocala in 2012 when I came home from Afghanistan for 2 weeks. I later on found some janky stuff they did in the suspension, sound system, and failed attempt at installing the snorkel. I imagine the original head on this engine cracked and they either replaced it or they bought a broke down jeep, got it running, and then turned around to sell it for a profit. Regardless, it ran fine before so I didn't bother checking the head bolts. If I would have the engine damage could have been completely avoided. Blue Devil would have never fixed this, but I wouldn't have found that out until I took it apart anyways. This is precisely why I say buyer beware. The only sure way to know whether or not BDP is going to fix your problem is through a leak down compression test which will pressurize the cylinder and reveals all the leaks. If you have leaks beyond the head gasket BDP ain't gonna help, unless you need something that will temporarily hobble you along. The picture with the snow is the buildup of BDP. It was like pudding, but it only seals hard in the oxygen exposed areas where there's iron or steel. I cleaned it all out and PB blasted it. Hopefully I will be able to turn the engine over so I can get the transmission disconnected from the engine so I can get it out finally. UPDATE - 12 -18 - 2017: Letting PB Blaster sit in the cylinders for two days I still couldn't break the pistons free (I did this last year after letting it only sit for a night and it broke up all the rust). Cylinder 5 was mostly rust and I could tell the PB blaster was working in there because the amount of fluid drained down low. Cylinder 6 with the BDP treatment stayed sealed to the cylinder walls. Trying to turn the crank by the bolt was stripping the bolt head and using the crank puller bolt holes with bolts in them was actually bending the bolts when I tried to use them for leverage with a breaker bar. Finally I resorted to the last resort, a sledgehammer right into the pistons. If I had any intentions of rebuilding the engine that is now completely out the window. Pistons are damaged as well as the cylinder walls. Pictures enclosed. Stay away from this stuff and get the work done by a mechanic. This is coming from a DIY person that does all of his own work and is all about saving money. This just costs you more in the long run and isn't worth the toil. Blue Devil will seal the deal on your engine's eternal destiny as it sucks it down into the junkyard pits of hell.

I purchased Blue Devil head gasket sealer and blue devil 3 in 1 radiator flush for a blown head gasket in a pt cruiser. Firstly I am capable of changing the head gasket, but am a single parent to two young kids and don’t expect to have that kind of time until they’re older, so I rolled the dice. The radiator flush is required for making sure the surfaces that need repaired are clean. This gives the sealer a better chance if “sealing” and should help the repair last longer. It’s application was simple and should be possible for anyone to do. However I was concerned about the 20 mins of idling. I didn’t need to be. Now the instructions for the sealer seemed a bit much until I considered what it was for. My car required removing the thermostat housing and since the thermostat gasket is what sealed the housing I had to use the gasket. My system uses 2 gallons of coolant so I first poured in 1 gallon then half the bottle of sealer and topped it off with regular water(I didn’t have any distilled). I did this with the engine off because of how bad the leak was. 50 mins of idling seemed like a lot for something that would overheat in 20, but the temp never went above normal. As per instructions after the idle time I let it cool off and then reinstalled the thermostat. I was presently surprised how little liquid the vehicle had used during the idle time and thought that was a great sign. After the coolant got topped off I had to drive a lot further than I had in a long time, and the temp again never went above half way, but what did surprise me was the restored fuel efficiency and performance(gutless car to begin with so any improvement is noticeable) as well as how smooth it ran. I am now a believer. Considering it’s been less than 24 hours I cannot comment on its life span, but will if it fails. I don’t expect it to. I’m hank you!!!

I purchased this in mid May for a GMC Diesel 6.2 Vandura I inherited from my father. The engine runs good but was pressuring up the radiator and overheating and I replaced the radiator with a new one and a new heater core and water pump and then discovered my cooling system was getting pressure, most likely from a compromised head gasket. I followed the directions exactly and got some benefit from this (less pressure now and no overheating) but I decided to buy a second bottle and try one more time to seal off all remaining blow-by. I'm going to use the second treatment and run the engine much longer than the instructions state to ensure that the sealant gets into every nook and cranny. The first attempt did OK, and I'm confident the second treatment will complete the process and render good, final results. I'll post a follow-up when I "git-er-dun." Although I like the product, both bottles (the one I bought in May and the one that arrived 7-2-2014) were leaking profusely upon arrival. What a mess. Whoever makes this stuff doesn't tighten the lids very well and/or the seller doesn't look at the lid to see if it is screwed on very tight. I'll try and upload a video showing me opening the box as it arrived wet. And I'll also try and update on the success of sealing my pressure leak on my second try. If Blue Devil can seal off a leak in a high compression diesel engine (probably a head gasket compromised) I think it would be really good on a regular gasoline engine.

Amazing product it made me a believer