12 Ways of How To Test A Blown Head Gasket Compared- PART1 

Never on RU-vid have I ever seen a guy like you who is so well educated and informed and such a good teacher to those of us who dont know much about our cars. I have learned so much from you in just this one video because you took time to explain that all that glitters may not be gold which is so true. I really wish that more guys on RU-vid would be as good as you and as educated as you in informing us how car engines run and what tests are available to test things that could be very costly in the end. So keep up the good work and Thank you so much for taking time to educate us!

This is the best series of videos I have ever seen on blown head gaskets. Well done, Dude!

Wow, you explain it in great detail .Finally i am understanding how this all works. Keep up these excellent videos, please. I have liked and subscribed.

awesome experiment and an awesome trans am! Thanks for the upload

A blown head gasket is definitely a generic term I use it when describing my wife quite often when she's angry

One thing that makes your videos so completely enjoyable, in addition to the fantastic knowledge you share, is that you have great wit that you shoot off at the most unexpected moment. You also have a tendency to go on a spontaneous colorful rant in the middle of you lectures, and I like that a lot too. Your channel is great.

TY, it's on a 79 GMC that my dad left me. He bought it new in 79. I just lost my mom in Feb. they both loved this truck. It's got about 165,000 miles. I always knew I was gonna rebuilt the engine and so noes the time. I'm gonna go .030 over, cast Pistons, mild hyd cam, double roller chain, high volume oil pump and a three angle valve job . Decked, squared , line honed and balanced. Keep it a daily driver. Mom and pop will be happy and so will I. I just bought a good spray gun from Eastwood and going the satin black on the body.

oh wow, you've given me the knowledge and understanding I need to know about Head Gasket. I previously own an 2003 Buick regal ls. After church Tuesday my engine started smoking took a look at it today it the smoke was coming from that area. This actually helped my curiousness. Thanks :-)

thank you for taking the time for videos, you sir are awesome!!

As a shop owner, I like to watch these type of videos to always learn something new but more to catch people doing something stupid. I watched the entire thing and enjoyed every second. You are doing a great job. Keep it up. :)

I have one of those 4.3 chevy's from 2000. The intake manifold leak was obvious. Now rebuilt. the noise's I am hearing sounds like a 'bad' 'blown head gasket'. Lots of that mud sludge creamy. Should be a fun spring fixing. Thanks for sharing your troubleshooting techniques, really helps me wrap my head around the problem.

Very thorough and informative THANK YOU SO MUCH! Very well done!

Great to see this done scientifically, with a little more time than most flat rate mechanics would spend.

im a gal and i wish i had seen this before i bought that used pos..really want to see the steel seller video.. thanks

I'd give you 4 thumbs up for the two videos in this series, 2 for each, if I could. I like that you show so many different ways of testing this from the most sophisticated to the least... SUBSCRIBED!

Really helpful! I’ve had a shop tell me blown gasket but I don’t think so but no sure what it is ... misfire #5 and replaced coil and spark plug but same ... has never overheated but misfires when idle .. I bought the scientific test you showed first and it passed with flying colors ... still testing and using your videos - thank you so much for taking the time

Good information. I never knew there were this many tests. One thing I have learned over the years is if a vehicle starts to overheat due to a suspected blown head gasket, pull over and shut the motor down for two minutes or so and restart. The shut down will allow the hot coolant to bathe the thermostat and it will open. Just a stop gap, of course, but it can give you a chance to get home or to a shop. All of this assumes the driver keeps an eye on the temp gauge... a very big assumption.

I really appreciated your demonstrating these tests with a control and distinguishing the limits of what they indicate and prove or disprove. I was skeptical of the chemical CO test you did first, but I feel more confident in that method now.

You are my favorite vehicle teacher. What you teach is so helpful! Thank you!

You are always the best in this field .. keep going.

Great video. Where could I get a Carbon dioxide tester like yours from? It seems like the easiest test for the average joe. I am looking to buy a bmw e46 and where I am from they get driven hard, so I need to be confident head gasket isn't an issue. Thanks so much

I found this on another webpage and I thought that it was interesting: Hi all. Great Article, but just a bit of a correction. Adding oil makes it a wet compression test. A leak down test is when compressed air via a compressor is used to pressurize the cylinder whilst the piston is at top dead center. At this point the intake and exhaust valves are closed creating a "sealed" chamber. The level of air loss determines the condition of that cylinder and it's associated components. So... if you have a high loss of air you should be able to work out what has failed. If you hear an excess of air venting from the intake.. the inlet valve is damaged. An excess from the exhaust... the exhaust valve is damaged. Pull the dip stick... hear an excess of air from here and your rings are shot, or head gasket leaking into oil gallery. Bubbles in the coolant and you've got a head gasket leak into a coolant gallery. This test is normally done after a compression and wet compression is done. It is the most accurate but much more time consuming to set up.. Hope this helps guys...

I'm a newcomer to your video presentations, I just happened to stumble on the one you did on fuel trims which I found fascinating and illuminating, and now I found this one which further proves that there is a genius behind the videos. Keep it up Matt, I just wish I had discovered you sooner

Occam's razor applied to diagnostics/repairs on cars... love this channel!

good mechanic

22:25 to 22:35 Guy checks cap for white sludge, said it looked fine.... Shows to camera and there definitely white sludge in it! lmao.

Very well done. Very informative, to the point, and no annoying music. You rock. I'm surprised you don't read plugs though. Plug condition can give you some good info.

The best series I have ever watched. Tnx

"that was more annoying than listening to a liberal" lol you caught me off guard there

O.K. "more annoying than listening to a liberal". That's hilarious. Thanks. I needed that.

Amazing presentation! Thank you for this. Now I understand how to test head gasket for myself.

Wow! This guy really knows his stuff! Absolutely no guess-work here; it's all scientific evidence. By a clear country mile, the best head gasket video on RU-vid.

In a real blown head gasket situation = engine is toast, car undriveable, check engine light flashing = get a new car or new engine, depending on blue book value. The cost of a HG repair job is outrageously prohibitive and will probably not remedy all additional latent engine damage in domino effect result of a real blown HG. Coolant in the oil = engine totally screwed. A blown HG is bad news. A minor leak where CO2 and coolant are slightly mixing is the red flag indicator that things will just get worse and why it is crucially important to perform a full engine coolant flush per manufacturer schedule with the proper 50/50 coolant. Never allow garages to top up the coolant. Almost all garages just do the drain & fill routine. That's no good. The system has to be completely flushed and replaced with perfect 50/50.

Anyone else want to admit.. You're here because you have a Subaru? 😂😬

Fantastic video! I found this to be very informative.

This was amazing. SOO much information. Thanks! (and thanks for wearing a mic :))

"more annoying than listening to a liberal" I lost it laughing! I knew I liked this guy

"That was more annoying than listening to a liberal." @15:20 -LOL, love that comment.

Absolutely fantastic and educational video! Liked and subscribed.

Thank you! Your cartesian methodology and precise sens of details got me subscribed! I really liked the name of the channel, hell the cat is alive'n kicking 👍

A milky oil cap can be simply from cold weather condensation.

more annoying than listening to a liberal? Im subbing! Great source of info, you have.

best video for engine diagnosis ever seen. Lerned so much Thank u :)

Awesome fixing to watch part 2 very well explained

Great informative video. Like the Liberal comment... Got to find part 2 lol...

"More annoying than listening to a liberal" LOL Thumbs up!

I'm an auto technician of 35yrs & your video is well done very thorough. Great job!

This guy is good! Great video, very informative. Like the scientific angle good attention to details keep it ☝!

I gave you a thumbs up immediately after saying the compressor noise was more annoying than listening to a liberal. Personally I would rather hear a dog barking than a liberal.

"More annoying than listening to a liberal" - lmao.

great video very well done this guy walks you through step by step . All his videos are exlent .Love it BILL PENN from PHILA PA POSTED 5/10/18

great video! my car is well looked after and my gasket is intact (thank god!) very educational, from London, England, thanks!

more annoying than listening to a liberal. lol damn dude your a winner in my book.

"THAT WAS MORE ANNOYING THAN LISTENING TO A LIBERAL" ROFL That's going to get you a ton of dislikes, but it was hilarious!

Thanks for putting this up!

Very cool video. Lots of options for testing. I was really surprised one of the spark plugs didnt look different.

Love It! MAGA!

"more annoying than listening to a liberal" Subscribed

This is the first video that I seen of your and love the way you explained things. Now I'm going to watch more of the other videos you have hope there just as good. I'm a fan now.

thanks for taking the time! I am no scientist but I still enjoyed both of your headgasket diagnostic videos. one thing I ponder is if you have gone out of your way to find out where the air goes in a car with a cracked head or block after performing the compressed air test. what mean is if you have noticed this air flowing out of the pcv valve or oil cap or the like. I would be interested about your findings on that type of scenario. excellent work.

Sad but true, I have to change my head gasket. This video is just great, clear explanation and testing. How did you get so good at this? Being a molecular biologist is a handful. I'm trying to do well at this by watching guys like you and I'm a musician.

Great video! Unfortunately, I have torn apart much of the vehicle after diagnosing a bad water pump, due to several overheating episodes and disappearing coolant. (Water pump was diagnosed by no movement of coolant in the radiator when running with cap off and then removing accsy belt and being able to freely spin the pump.) The timing cover is filthy and so is the underside of the vehicle, seems it has been loosing coolant for some time! Then after seeing the amount of coolant everywhere, even in the crevices under the intake manifold, I suspected leaking of the head gasket. At this point I have the intake off, Throttle body off, radiator off, valve covers off, but yet tried the leak down test and not sure what to make of it. First, I set the Compressor at 75psi but suspiciously only would see 30psi on my tool psi...... once connected the tool to each spark plug (at TDC), I only got one of 6 cylinders to read less than 20% leak. Other cylinders were off the charts, like 90% plus and the tester psi dial 0 and some of those cylinders would make noise, air gushing out mosting from adjacent intake, while others reading 90% would not make any noise. Given the tear down condition, can this test be useful at this point?? Just wish I had used the bulb test BEFORE tearing apart! Now I almost think I should proceed with the water pump/timing chain replacement and reassemble, then do the bulb test and if that is bad another tear down!! Or do you think there is a definitive test I can do with the tear down I have done or just proceed with the cyclinder removal/inspection/gasket replacement since I am already to this point? Worst part is that this is a 2003 Suzuki Grand Vitara and I am learning these are awful to work on!!! Regardless, I am repeating the leak down tests, but think my tool may be bad??? First off I should see same pressure at tool as I set my compressor no? Thanks!

Amazing video like always! :)

Well articulated. I just want ton add that the bock can warp too -particularly aluminium blocks.

Really Great stuff ! Really the amount of forums I've read for clear answers if my head gasket has blown! Then i found this goes through the lot and you even despell the false readings you can get. You obviously take great care and time in creating these videos, big thank you for sharing your knowledge. I will use to check mine now. Just one thing, if when running the car with the radiator cap off and you rev the engine up if the coolant pumps out of the radiator does this tell you your head / block is blown or it that normal?

Very informative. Thank you for this video.

Great video. I learned a lot. Thank you!

Nice & thorough walk thru of the subject. Go back and read your spark plugs. You’ll find #3 shows a ‘washing’ has occured. This corresponds with your positive #3 wet paper test.

Really informative, nice job

Thank you so much. You provide so much valuable information. You're a great teacher.

Fantastic video.

I like the control element of having a test on the second known car to confirm test equipment is working. Nice.

Mat hi you have explained this better for me than anyone else on yt has and I have researched a lot of these videos thank you for this video so now I have a better understanding now after hearing your video

Excellent Information

Love your videos. I'm pretty sure I have a blown head gasket on my 1998 F-150, I will do the compression test to confirm. One of the indicator's I have had is I can smell combustion products in the degass bottle (coolant reservoir) when I take the cap off, you may want to add this to your shade tree mechanic inventory of tests, although not as definitive as the bubbly oil, I really like that one.

Nice instructions. Thanks! Question for you, as to what product and how much you think I should use. I have a 1995 Subaru 1.8L 4-CYL boxer Impreza, 177,000 miles. I have 76 and 78 PSI dry compression in #2 and 4 of one head (driver side). This started a few days ago, we noticed while on a highway trip the power was weak and I can hear it missing as the RPMs drop from driving to idle. I don't have overheating, excessive oil consumption (drippy seals, I add a quart about every 900 miles), smoking, or fluids cross contamination. I'm waiting to have a leak down and another dry/wet compression test at a different shop. The first shop only did dry compression and wasn't too bright or helpful. If I end up having a head gasket leak between those two cylinders, what products would I possibly try to mend it? It must not be too bad of a leak, whatever it is, for the compression to build to 78psi dry. The other two good cylinders are 130ish psi. If it ends up being a valve leak, what products and strength could I try to get them clean? After cleaning, I will have valve clearances checked, as it's probably never been done.

Very good demonstration of the tests! I'll be checking out my Honda CR-V today. Hoping for no yellow test fluid...

YOU HAVE REALLY SHOWN AND EXPLAINED WHAT YOU ARE DOING AND THE RESULTS. I APPRECIATE YOU VIDEO AS I'M HAVING ALMOST THE SAME PROBLEMS. COMMENT BELOW IS RIGHT ON. THANKS A MILLION, I COULD USE A FRIEND LIKE YOU HERE IN MIDDLE GA!!!

Great video man. Thanks!

I'm losing coolant with no leaks showing do I'm thinking its blown head gasket. This is a great video. You know your stuff. Ty

Thankyou Dude cause this problem is a pain in the butt , too much money too many directions , I like to one stop , it's hell just working on these things

Thanks again man, that was cool

Great video! The paper dye test is different but very cool

thank you for great informative video .

Excellent, great teacher, great mechanic.

@Schrolingers Box First off Thanks for the reply and Thats makes sense and its a 04 Volvo C70 5cyl 2.4L haven't did any compression tests as of yet... but did find a leak as if maybe it is a freeze plug behind the exhaust manifold on the back of the motor, can get car to start to do any kind of compression test.. car did run hot though, and did crank up after being allowed to cool down, didnt give it any gas then shut down and hasn't crank since... was thinking it could be a head gasket also since there is not enough compression to crank up.. any input you have is much appreciated.. thanks for your time

Thanks for the tips, great video. I looked in the comments but does anyone know what the first co2 tester was called?

Great video ! watching now , going to do the first test tonght on my dAKOTA , been having trouble since buying it with not hot heater and hearing bubbles in dash . Also while burping the cooling system yesterday I noticed the lower rad hose was not even hot after running and revving the engine for over 20 minutes while burping witha spill free funnel . I burped alot of air from the system and heater is working a bit better but it seemed that the bubbles may have continued to come up if I kept running it . I have heard maybe my thermostat is stuck open . First I will test for blown head gasket then if not blown move to replace thermostat .... At ez lube I had a coolant replACE done and they suck it out , I was a moron and wanted to try to flush my heater core so I left it running with heat on for awhile while they were sucking out coolant then shut it off before it was done taking all coolant out , how bad is that ? I had a light bulb go off while doing it and thought whoooo this is not a good thing to be doing ! Do u think anything bad could have happened ? My temp gauge was fine the whole time and after , never going high ..

really great video thanks for the info

Bro you are one of the best. Good knowledge about car

Very helpful video, thank you :)

Awesome video. Very informative!

Thanks for teaching me !!! Biiiiiiiiig Respect from the UK

Hey Matt…I have the day off today so I was happy to see these 3 recent uploads! Just finished watching part 1 of your head gasket tests and very good video for sure! I was able to pick out which plug was from the cylinder that was burning coolant just by looking at it by the way. I didn't get a good look as you were moving the plugs around quite a bit but there was a moment where you could see a noticeable white "crusty" looking spot on that one plug that was visibly more pronounced than on any of the other plugs. It was on the underside of the curved electrode (the side that would be furthest downward in the chamber while installed in the car) In my experience in the field I have never seen a plug that was burning coolant that didn't have noticeable white deposits. I wouldn't call a head gasket based on this visual inspection alone, but reading plugs is very useful for helping in what diagnostic direction you want to go in :) There is some good info out there on the net about plug reading, and I think you may come to like it. Just another little weapon for your arsenal to help in finding direction. Great vid!

Well done but did anyone else think he may have missed on the Shade tree method of looking under the oil fill cap and noticing what looked to me at 22:31 "Engine Mayonnaise" that was in the center underside of his oil filler cap. It usually is found there and is caused by oil and water and heat mixing together to produce this milky whitish slimy film.

I appreciated the emphasis on diagnosis. I'm an orthopaedic hand surgeon by trade, and I entertain myself (and save money) by working on cars and boats. I appreciate the scientific approach. I love the "plug and pray" analogy from another video. I see that a lot on youtube and mechanic shops actually. One of my mentors in orthopaedic surgery always taught, "an ounce of diagnosis is worth a pound of cure, so do a pound of diagnosis for every ounce of cure." I think that philosophy applies to this field as well.

I'm a girl with almost zero mechanical knowledge and found these videos in hopes to help my husband who enjoys looking up how to fix our vehicles. These videos were actually interesting and your humor is great. Especially the part of about annoying liberals. I laughed out loud while cleaning house alone. I realized I wasn't listening to talk radio, I was on this third video! Good job!

Thanks, great video, I think I have exhaust in coolant. I'll buy a kit and test it. I was hoping there was a scientific way to check for exhaust gasses.

Great video Schro!

That’s a very informative video thank you very much