I had coolant dripping behind my Northstar engine. I borrowed a pressure tester for the cooling system, and I could hear a hiss behind the engine, at the height of the head gasket. I put dye in the coolant to look for the leak, but saw nothing on the engine. I got one of those blue liquid testers, and after I pumped it a lot the blue took on a yellow tinge. I took the car to my mechanic after I saw what it takes to deal with a Northstar head gasket, and told him I was sure it was the head gasket. He called later that day and said it was just my coolant reservoir leaking. The reason the blue liquid was turning yellow was that I was sucking some of the dyed coolant into the tube. What a blessing to have an honest, capable mechanic for the jobs I can't do myself. I bought him and his whole shop lunch.
Schroeders box had a vehicle with a small leak . He did not have a gas analysier . He used cylinder leak down on the suspect cylinder and found bubbles in over flow tank . That gas analysis is awesome
Thats the way i have done for decades.but my new favorite now is differential pressure transducer and a scope,will pinpoint exact cylinder and can do on load and idle
My son's car was over heating. The first shop change the thermostat. The second shop, said everything was wrong and had a huge list adding up to over $3,600. It was a head gasket and I use the blue liquid tester. Some cars are just prone to head gasket failure after a given amount of miles, due to their design.
I always thought it was strange that the analyzer probe could sit in the muffler pipe and absorb moisture into them from the exhaust but unable to handle any amount of coolant into them. Great vid thanks!
Always appreciate your no nonsense, cut, and dried, evaluations and solutions! I am an old-school mechanic starting out in 1974 sometimes it was very easy to detect and gasket failure but sometimes the small ones were very difficult to find... thank you
Thank you, as always, for your clear explanations and showing the way a high-end shop would do things. I also want to say, the camera operator does a consistently good job. One question that doesn't actually matter but... is the liquid (in the 3rd option) reacting to CO2 or hydrocarbons or something else? I noticed it says "CO2 Leak detector" -- but obviously it will react according to the liquid inside, not what the plastic instrument has written on it. Thanks again, Professor!
I had a 10' Corolla with the 2ZR-FE engine 1.8L. The car reached 306k and then it started misfire on Cyl 1. It never overheated, and it was very well maintained. And even still I had a blown head gasket by itself. It never overheated. It only had one fan and it always worked. It just started developing that misfire for like a month only on Cyl 1 during start up. After 10 seconds running it will run smoothly.
Scope with a pulse sensor can be used as well. I have even triggered off one of the coils and you can figure out which bank is the bad gasket. Still replace both, but nice to know so you can inspect the gasket when you’re performing the repair
A head gasket test on an inline 4 is relatively easy as demonstrated in the video, because you only have one head and only one head gasket. But, what do we do when the engine is a V engine with two banks, and hence, two heads and two head gaskets? How do we identify which gasket is bad? In diagnosing the vehicle we have to find which cylinder(s) are compromised, because we need to report to the customer which bank has the bad head gasket. For V engines I like to use the coolant pressure pulsation method to identify the bad cylinder (usually I find only one cylinder is compromised). So, perhaps you could do a video on how to determine which bank on a V engine has the bad head gasket. I know, as a matter of process, that most shops who want a quick diagnosis, will just tell the customer they have a head gasket problem, which is fine unless the customer asks (or a shop they hire to do the work asks) which bank has the bad head gasket. For a proper full diagnosis you results should pinpoint the bad cylinder(s) and bank(s). I find it beneficial to be able to inform the customer which cylinder, and by extension, which bank has the bad gasket, especially for DOHC engines. Most shops would recommend both gaskets be changed in order to provide a warranty on the repair. If only one side is changed, I find, there is usually no warranty issued. This does, however vary from shop to shop.
You said the tip of that first probe should never get into moisture or get wet, but you also said it goes in the tailpipe. How does that work when so much water comes out of a cars tailpipe?
This may be my ignorance but I have a question about what these head gasket test also have the same results if you have a blown intake manifold gasket and how would you know which one it is thank you. I love your show. It’s my favorite channel on UA-cam.
Thinking the HC readings ate jumping around because of firing order. When the cylinder(s) near the head gasket leaking are coming up on compression it's pushing the HC's & they they get lower until that cylinder comes around again.
Dear Sir, it is as well very important to make a cooling system pressure test, as well as check the radiator for clogging by uplifting it from car and block the bottom hase outlet, fill it with tap water and check for adequate flow. Also some cars like some Mitsubishis can have a frayed water pump impellar and some other brands can have a plastic water pump impellar that would be eroded. Sometimes people will unknowingly use tap water that could potentially lead to such overheat in extreme summer conditions. You know sometimes in your case where the engine is smooth with no mix of oil/coolant and no apparent bubbling in the coolant when you open the radiator cap, and due to economic situation, the car could live for so many years provided that the client check his oil and coolant daily. This did happens (at my end of the world) ) on a variety of Japanese and American brands, but you should even in your case remedy the root cause of overheating before relplacing the headgasket. Also sometimes a leakdown tester can prove which cylinder is bubbling to the radiator cap so as to imform the machine shop accordingly. Also, a boroscope could show a tiny green bubble into the cylinder provided that the owner uses a coolant. Take Care. John
Had a Toyota High lander. Always had a coolant odor after driving. Never could find a leak. And needed coolant added after a thousand miles or so. The thought of head gasket never entered my mind. One day the failure was catastrophic and non- repairable. So, if you smell coolant and can’t find a leak… you’re losing it thru the exhaust. That’s where I think I was getting the odor from. There was never a residue under the oil cap, or evidence of crankcase contamination.
The cheapest way to preliminarily test is to pop the radiator cap on a cold engine. If air pops out at you then you know you either have a bad head gasket or potentially a cracked EGR cooler... I think gas analyzing is kinda outdated at least for new cars. EGR coolers internally leak and will introduce combustion gas into the cooling system. The best method that is cheaper then your first two tools would contend for a borescope, followed by a cylinder leak down test.
This would certainly lead you in the right direction but you’d have to do further testing to make sure your data isn’t caused by rings/valve seats. The tests shown here 100% points to a headgasket.
All 3 test are valid but their is a but what if the vehicle has an egr cooler that is blown those test will show positive for a blown head but its not its that
I had coolant dripping behind my Northstar engine. I borrowed a pressure tester for the cooling system, and I could hear a hiss behind the engine, at the height of the head gasket. I put dye in the coolant to look for the leak, but saw nothing on the engine. I got one of those blue liquid testers, and after I pumped it a lot the blue took on a yellow tinge. I took the car to my mechanic after I saw what it takes to deal with a Northstar head gasket, and told him I was sure it was the head gasket. He called later that day and said it was just my coolant reservoir leaking. The reason the blue liquid was turning yellow was that I was sucking some of the dyed coolant into the tube. What a blessing to have an honest, capable mechanic for the jobs I can't do myself. I bought him and his whole shop lunch.
even if he was a dishonest mechanic he'd probably not wanna do a northstar headgasket anyway
@@neverending774 True that! I just watched the video of it and almost threw all my tools away!
It’s always a GM motor, typical for here in the UK. One of the reasons we avoid Vauxhall Astra, Zafira and Corsa
Zip tie a rubber glove to the neck of the tank and see if it balloons up when the engine is running. Have a God bless week. I appreciate your videos.
same deal with an egr cooler bud nothing like a faulse possative to f u up
@@figol6272
Don't forget the Pentastar oil cooler 👍🏻
Fellow shop owner here 35 years, gotta tell ya I really enjoy your channel - keep up the good work!
25 year tech I would love to work with you and your level of expertise. I soak up knowledge from you guys. Thanks for doing the videos.
Schroeders box had a vehicle with a small leak . He did not have a gas analysier . He used cylinder leak down on the suspect cylinder and found bubbles in over flow tank . That gas analysis is awesome
Thats the way i have done for decades.but my new favorite now is differential pressure transducer and a scope,will pinpoint exact cylinder and can do on load and idle
My son's car was over heating. The first shop change the thermostat. The second shop, said everything was wrong and had a huge list adding up to over $3,600. It was a head gasket and I use the blue liquid tester. Some cars are just prone to head gasket failure after a given amount of miles, due to their design.
I always thought it was strange that the analyzer probe could sit in the muffler pipe and absorb moisture into them from the exhaust but unable to handle any amount of coolant into them. Great vid thanks!
Ohhh I like that 5 gas analyzer method! That’s sweet!
Always appreciate your no nonsense, cut, and dried, evaluations and solutions! I am an old-school mechanic starting out in 1974 sometimes it was very easy to detect and gasket failure but sometimes the small ones were very difficult to find... thank you
Thank you, as always, for your clear explanations and showing the way a high-end shop would do things. I also want to say, the camera operator does a consistently good job.
One question that doesn't actually matter but... is the liquid (in the 3rd option) reacting to CO2 or hydrocarbons or something else? I noticed it says "CO2 Leak detector" -- but obviously it will react according to the liquid inside, not what the plastic instrument has written on it.
Thanks again, Professor!
I had a 10' Corolla with the 2ZR-FE engine 1.8L. The car reached 306k and then it started misfire on Cyl 1. It never overheated, and it was very well maintained. And even still I had a blown head gasket by itself. It never overheated. It only had one fan and it always worked. It just started developing that misfire for like a month only on Cyl 1 during start up. After 10 seconds running it will run smoothly.
Scope with a pulse sensor can be used as well. I have even triggered off one of the coils and you can figure out which bank is the bad gasket. Still replace both, but nice to know so you can inspect the gasket when you’re performing the repair
A head gasket test on an inline 4 is relatively easy as demonstrated in the video, because you only have one head and only one head gasket.
But, what do we do when the engine is a V engine with two banks, and hence, two heads and two head gaskets? How do we identify which gasket is bad?
In diagnosing the vehicle we have to find which cylinder(s) are compromised, because we need to report to the customer which bank has the bad head gasket. For V engines I like to use the coolant pressure pulsation method to identify the bad cylinder (usually I find only one cylinder is compromised). So, perhaps you could do a video on how to determine which bank on a V engine has the bad head gasket.
I know, as a matter of process, that most shops who want a quick diagnosis, will just tell the customer they have a head gasket problem, which is fine unless the customer asks (or a shop they hire to do the work asks) which bank has the bad head gasket. For a proper full diagnosis you results should pinpoint the bad cylinder(s) and bank(s).
I find it beneficial to be able to inform the customer which cylinder, and by extension, which bank has the bad gasket, especially for DOHC engines. Most shops would recommend both gaskets be changed in order to provide a warranty on the repair. If only one side is changed, I find, there is usually no warranty issued. This does, however vary from shop to shop.
You said the tip of that first probe should never get into moisture or get wet, but you also said it goes in the tailpipe.
How does that work when so much water comes out of a cars tailpipe?
This may be my ignorance but I have a question about what these head gasket test also have the same results if you have a blown intake manifold gasket and how would you know which one it is thank you. I love your show. It’s my favorite channel on UA-cam.
What is that thing that can't be spoken of ? 7:56
exactly i want to know
exselente dianostic master en mi olmilde opinon tabien te pudes aser la tester cylinder lean down tester
Thinking the HC readings ate jumping around because of firing order. When the cylinder(s) near the head gasket leaking are coming up on compression it's pushing the HC's & they they get lower until that cylinder comes around again.
GREAT INFORMATION ..........!!!!!!!!!!!!!!!!!!!!
How do you distinguish between a failed head gasket and a cracked head or block?
awesome.
Dear Sir, it is as well very important to make a cooling system pressure test, as well as check the radiator for clogging by uplifting it from car and block the bottom hase outlet, fill it with tap water and check for adequate flow. Also some cars like some Mitsubishis can have a frayed water pump impellar and some other brands can have a plastic water pump impellar that would be eroded. Sometimes people will unknowingly use tap water that could potentially lead to such overheat in extreme summer conditions. You know sometimes in your case where the engine is smooth with no mix of oil/coolant and no apparent bubbling in the coolant when you open the radiator cap, and due to economic situation, the car could live for so many years provided that the client check his oil and coolant daily. This did happens (at my end of the world) ) on a variety of Japanese and American brands, but you should even in your case remedy the root cause of overheating before relplacing the headgasket. Also sometimes a leakdown tester can prove which cylinder is bubbling to the radiator cap so as to imform the machine shop accordingly. Also, a boroscope could show a tiny green bubble into the cylinder provided that the owner uses a coolant. Take Care. John
How do you know if it’s a bad head gasket vs a possible failure in the head itself
You don't. Either way, the head must come off and pros will always send it out to be checked.
Had a Toyota High lander. Always had a coolant odor after driving. Never could find a leak. And needed coolant added after a thousand miles or so. The thought of head gasket never entered my mind. One day the failure was catastrophic and non- repairable. So, if you smell coolant and can’t find a leak… you’re losing it thru the exhaust. That’s where I think I was getting the odor from. There was never a residue under the oil cap, or evidence of crankcase contamination.
Pulse sensor testing is another way as well
With a Powerstroke 6.0, it's best to test it under load driving. You put a gauge on the cooling system.
Yup. Piles of 💩 too. They ran poor under warranty. Almost 20 yrs later, still 💩
A cylinder leak down test would be another way.
Nice video for sure.
The cheapest way to preliminarily test is to pop the radiator cap on a cold engine. If air pops out at you then you know you either have a bad head gasket or potentially a cracked EGR cooler... I think gas analyzing is kinda outdated at least for new cars. EGR coolers internally leak and will introduce combustion gas into the cooling system. The best method that is cheaper then your first two tools would contend for a borescope, followed by a cylinder leak down test.
I see those engines cracking in spark plug threads.
How do i prevent a head gasket from blowing?
Hi I would like to buy a scanner diagnostics for personal use that can erase errors and very good one. What you advise for me please thanks
Surprised you didn’t use scope and pulse sensors/relative compression.
This would certainly lead you in the right direction but you’d have to do further testing to make sure your data isn’t caused by rings/valve seats. The tests shown here 100% points to a headgasket.
@@rotarynerdpulse sensor connected to coolant tank.
@@matthewbrice737 i apologize. I misinterpreted. that would definitely work
All 3 test are valid but their is a but what if the vehicle has an egr cooler that is blown those test will show positive for a blown head but its not its that
Is that the goldfish from the why files?
Thank you!!!!
Whoo!! First One 😂
Dang it, I feel bad for her, someone sold a car with a blown head gasket.
On a diesel with an egr cooler failure you could get stung with all 3 of these methods
What can he say on UA-cam as a auto mechanic?