Great video and it's so simple. I like the low hanging fruit concept. It's funny because when I saw Brandon's face I knew it was a video that I would learn something. This guy knows and knows how to explain the fine working details. I'm one of those people that has to fully know why I'm doing something before I will use it even though it's a popular test Brandon breaks it down
Nice job Brandon. Complete explanation without wasted time like so many other TH-cam posters, including professionals. I am retired from 45 years as a technician and love to keep up with what is going on in the trade.
A million thanks for all of the feedback. Thank you all for investing the time to watch. To answer a few questions, the RC Test, monitoring for voltage-drop is almost as accurate as current measurement. The difference in reliability is minimal. I recommend applying this test to a known-good vehicle. Then, try removing a spark plug (to create low-compression in one cylinder) and repeat the test. There is NO BETTER WAY TO LEARN this valuable technique! I use it EVERYDAY 👍
No, thank you for taking the time to teach us. As someone else mentioned, I thought a RC test could only be performed with an amp clamp. Have an awesome year!
Hi Brandon I am motor nechanic for over 50 odd years (15 years in Europe, rest here in Adelaide, South Australia. Still have opportunity to learn a lot. Thanks for posting it. Time watching new techniques is time well spend. George - QQMR
I am learning so much off this guy. Cant say i can keep up that easy , so i watch the video a few times for my slow brain. Fantastic explanations , very impressed! Thank you
I was at a shop for a different problem and I overheard another mechanic was bitching about removing the intake to do a compression test so I did a RC test and found he didn't have a compression problem he was so impressed he gave me $100 dollar bill!! Great job Brandon
So five years later i hit on this vlog, if that garage is yours and u own it top man, if that garage aint yours and you work there they aint paying you enough and your talent is wasted, great vlog great explanation , you have a great easy way to explain things that is instantly understandable, brilliant vlog...
Super helpful ! Wow ! Such an outstanding tutorial ! Extraordinary detail !! You provide precise coaching cues for us to do the procedure ; AND , include all the other pertinent information - namely, the “who , what , where, when , why, and how !! I’m learning lots from you ! Thanks mate !! 🙌🏼
An extremely well made video! Extremely professional and very well spoken! You are an asset to your professional, Brandon. All you NY guys (Eric O., Keith, Eric and more) are top-tier professionals! I am now a subscriber!
Excellent demonstration Brandon, thanks tbt for putting this info out there. It took me months to prove to my shop that rc is trustworthy. Id have to do it conventional just for them to feel comfortable with rc testing. Now they don't bother, i print the waveform, and they don't question, ever 🤣
Another excellent demonstration on using the scope to do a relative compression test. Finally the man behind the articles. lol Read some of your stuff on motor age magazine and its always a pleasure. Thank You Brandon for taking the time to teach and helping out the industry..
I had no idea you could do a relative compression test with a scope without an amp clamp! Great stuff right here - thanks for that one, Brandon! AC coupling right at the battery - I'd have never thought of that. 👍👍 Noticed Keith and Ivan making cameos in the background there - now that's a garage people will want to bring their modern, computer-controlled problem-children to. 😎 Happy New Year guys! 🍻
Kevin, thanks so much. I work with a great group of guys @Trained By Techs and it’s a tremendous team effort. We will have plenty more instructional videos to come 👍
Nice Diagnostic procedure, GREAT way to start off 2019 with Time saving accurate Diagnostics. This is a Perfect way to nail or eliminate one of the funnels I always talk about ( The Engine Integrity Funnel )
Excellent video as always Brandon! The power of the scope cannot be underestimated. Been playing with a pulse sensor recently and all of the opportunities it presents.
Brandon, that was an AWESOME video on compression testing. Now I really want to see a relative compression waveform on your Civic with a 20psi loss on cyl2...would that show up on the scope? Also we have to do a follow-up vid on Keith's van, since it actually DOES have a mechanical engine problem than the relative comp test didn't definitively show :) I have the vacuum Pico waveforms here for reference. It was so much fun hanging out with you and Chris and Keith on the Island, we should do that again sometime soon! Happy New Year!!
Another tip I like to employ that is equally as valuable as AC coupling, is to invert the scope leads on the battery, this will allow it to appear like a conventional RC test with an amp clamp.
I wouldn't, potential for blowing your scope if its connected to ground some how such as when connected to a mains powered laptop as you're effectively creating a short through the scope. Battery powered not as risky. Safest bet just use the invert function.
Awesome video,,,very detailed. Many thanks for sharing your knowledge and taking your time to help others wanting to learn the correct way of using a scope. Big thumbs up....
Brandon : I appreciate your time and knowledge . There is a company called Auto Ditex in Bulgaria that makes several diagnostic items , including a relative compression tester . It clips to the battery . The test can be unsynched or synched to ID each cylinder . It is a low skill level . I saw Diagnose Dan use it . There is also discussion on Scanner Danners channel . It costs $ 290.00 on E Bay , plus shipping . I don't know if a single channel U Scope from AES Wave can do this . But wouldn't you need the a second channel to synch the cylinders ? Again , thanks for the lesson . Bill .
Nice video and very well explained. It's a shame you didn't do the relative compression test on the first vehicule. It would have been nice to see if the relative compression test would have caught the weak cylinder that showed up in the conventional test and just how much difference would have shown up on the trace.
Hey Michael, You bring about a great point. The terminology “relative” obviously referred to how each current-peak relates to the next. Because is inferre s “starter-Load”, minor/normal variations in compression won’t make much of an effect on the current-trace. However, when there is enough of a shift in compression-differential to cause a drivability-symptom, my experience has been that the evidence is clear. Try it yourself, by loosening a single spark plug to simulate compression loss👍
@@brandonsteckler3417 Brandon, I was trying to find out if anyone had ever tied the two tests together. In other words would a 10% reduction in compression over the companion cylinders show up in a relative compression test, OR would it take 20, 30, or 40 percent before you'd see the difference on a relative compression trace? I was looking for the cutoff number?
I would assume it’s based upon the the vertical-resolution of the scope and would also take an accurate/responsive supplemental-voltage support, to maintain the accuracy of the test
SUBSTANTIAL Trained by Techs Brandon Steckler Tutorial brilliant video amazing from the start to finish loved it thank you very much Brandon Steckler Trained by Techs From Nick Ayivor from London England UK 🇬🇧
Great video!! AC coupling filters out the DC signal portion. I understand using AC coupling when testing AC ripple on an alternator (AC source) to block out the DC voltage to increase the image resolution on a scope. However I am a bit confused on how AC coupling is working in the video: relative compression case while we are using the starter's voltage drop (DC signal). The starter's commutator strips also generating AC ripple while it's revolving, no? Can someone dumb it down and explain how this actually works with AC couple/capacitor feature when it comes to relative compression?
Thanks for the reply Mike. AC Coupling will remove the DC from the circuit and simply show the "change" in voltage. Everytime a piston approaches TDC, the voltage will naturally drop due to the load on the circuit. AC coupling allows the scale of the tool to be much smaller (1-2v) which allows the drops in voltage to be more pronounced in appearance. Effectively creating a "zoom" feature.
Surely, Typically we view waveforms as reference to ground.When we view an AC signal, we think of it as one that varies above and below the ground line (meaning positive and negative). This is a true statement but it would be more accurate to say “an AC signal is one that varies above and below the reference point. When we AC Couple a Waveform, we make the reference point the average point or center of the waveform (not ground). If we then place the scope in a lower voltage range, we can view variations above and below the reference point (the average of Waveform. This technique serves as a ZOOM function. This works well on scopes that don’t possess great zoom capabilities. Does this make sense?
Fantastic explanation! I'm looking forward to Brandon's classes! Even vocally, he articulates so well! Check out Brandon's article in Dec Motor Age Magazine "The Importance of Asking Why...."
With all my respect to your experience Cylinder Compression test is an accumulative way of testing, some service info specify the number of piston strokes/revolutions to record the reading some do not mention anything, therefore it is essentially an accumulative testing so no matter how many compression strokes you go with, the air pressure inside to combustion chamber, the hose, and the gauge eventually gonna equalize on a definite Psi reading. Thank you for the great video
I love it when I learn new stuff. Fantastic video! I don't know why, but I just didn't consider voltage drop instead of current. 35 years I've been doing this. Duh-huh. Thank you.
Thanks for the video. If you are used to use the current clamp while testing relative compression you might want to invert the trace so the peaks of the signature align with the compression humps..... Or you can put your positive probe on the engine block and the ground probe on battery negative while you are DC-coupled in the 1 voltrange, makesfor a really good signature
Thank u Brandon. Can't wait to attend ur class in jersey for tst this month. Have a blessed day and a happy new year. All the big dogs in one shop. Wow😃😃😃
This is great information. Thanks. Question... Would the traditional compression test work with the schroeder valve removed? I didn't quite understand that.
This tech is truly a professional technician. I never even knew that conventional compression tests with the snap on compression testers with shrader valves can cause that... I guess i would've misdiagnosed then...
Better than that...I challenge you to try it yourself, on a known-good vehicle. Capture/post and tag me in it...tell us all what the test has shown you 👍
Brandon Steckler I see what you’ve done there and I like it, it shows how professional and committed you guys are to teach us 👍... unfortunately I don’t own a scope but I’m setting some goals for 2019 and a pico scope is one of them hopefully soon ... cheers
I believe on the ATS E Scan Elite , you can do a relative compression test , in SECONDS at the OBD2 connector . As well as a Volumetric Efficiency Test , etc. What about when you have to remove an intake plenum just to gain access , as well as risk breaking plugs , frozen plugs or baked on boots ? This could be done on the Snap On MT-2400 - about 25 years ago , with an amp clamp !
Awesome info!! I tried this on a Vantage. I chose lab scope dc volts, 1 volt scale and 2 sec time, then pushed the a/c coupling button. No pattern! Maybe i should chose 4 channel instead of dc volts? Maybe I'm just not recording properly? I a'm watching the vidio for the third time. I will try again tomorrow.
Awesome! Yes, the test comes in very handy. The best part....it’s quick/easy , yields a ton of data and can be applied to virtually all DC-motor started engines👍
I'm planning to start offering a RC test as part of a marine survey on boats. Plugs can be near impossible to access on some boats. Would you recommend to always do the RC test on a warmed up engine? Or as simple of a test as it is, maybe one test cold and then one hot...Might reveal more info
Thanks, you can clearly see the value in the test. Most-often the faults it reveals can be seen when the engine is cold. However, there could certainly be situation ms that arise where a mechanical fault will surface when an engine comes to operating temp. My advice...test under the conditions the “symptom” is present 👍
Lo interesante es que lo hiciste sin usar una pinza amperometrica al positivo del burro de arranque. Poner en AC el osciloscopio para la medida al borne negativo de bateria. Ingenioso. Felicitaciones
Thank you Brandon Steckler! Very well explained! I'm just wondering if Voltage drop test is as accurate as current drop test since voltage and current have different reaction times (problably not a considerably difference to set a noticeable difference at low cranking RPM tests) Just wondering.
Voltage drop and current flow are proportional to one another. In fact, You You place the both on the same scope, they are mirror images of one another , just inversely proportional
Hi, Great question. The key to successful and efficient diagnostics is understanding the limitation of the tools/tests being utilized. The relative-compression test (voltage-drop or amperage) simply displays the the load placed upon the starter as each piston, in-turn , completes a compression stroke. So long as the cylinder fills/seals similar to the other and has the similar stroke, the load should be the same. To answer your question, simply having oil on the spark plug means oil consumption is present but not necessarily a loss in compression. Does this make sense ?
Damn, I just cringe thinking about weak hood props and a hood crashing down on a new Snap On Zeus while I'm inside cranking over the starter. I think a quick go -no go relative compression test with volt leads could be done right inside car, off a DLC Line SPI. I'm too lazy to bother hooking to a primary wire of coil for a trigger unless I see a smaller dip somewhere between humps to justify wire piercing for a trigger to determine which one has a compression deficit .
Yes! Thank you for pointing that out. Anywhere there is access to source voltage/Ground can be utilized. The DLC is a great place to sample, right from the driver’s seat. You make the valid point of capturing a sync only if a fault is detected. It definitely saves time not to find a sync unless necessary. I appreciate your help, thank you!
I thought that was new level and pine hollow milling around in the back ground. Looks like some serious discussion was going on. Kieth seemed a little agitated. Lucky shop to have the big guns helping them.
I think Brandon teaches better than Kieth , that is , he slows his thoughts down so the viewing audience can stay up. Kieth knows his sh&t, but skips a lot of his demonstrations, as he probably saying to himself they (the viewers)should already know this stuff. And no Kieth , I watch everyone of your videos but scratch my gray hair afterwards. lol.
Yeah , I just assume that everyone will get out there and seek the training. Not just the free stuff . But the thousands of dollars worth that I spend every year. The sacrifices and effort that I put into receiving my own training , well the only way to get paid back for those is by fixing cars for a living, not TH-cam. So I'll never spend the time to make very long drawn out videos. There is no benefit. I already lose enough time and money to help where I can for free. Take those moments where you're lost after the video and use that as your incentive to go get some training . Cheers
Keith is an absolutely phenomenal diagnostician. We have to keep in mind that Keith is “working “/running his business” all while sharing his videos with us. It takes a tremendous amount of concentration and thought to get, what you were trying to share, out there for viewers to see. If Keith took the time to break down every thought, to the most basic point of view, his videos would be hours long, and not as well received. I appreciate the support and the complement but will remind you I did that video with all of those Fellas , with no time constraint at all. This is why I had the luxury of taking my time to articulate.
Keith is just sharing some interesting observances when he comes across them. most people viewing Keith's channel have some knowledge in this field know what's going on in the video and is more of a guys look what I found out keep this under your hat if you come across this issue on one of these type things.
![Compression Test with a Scope [PicoScope, Autel MP408, Micsig, & Autel Ultra]](http://i.ytimg.com/vi/w8CyhpWXG5E/mqdefault.jpg)
Great video and it's so simple. I like the low hanging fruit concept. It's funny because when I saw Brandon's face I knew it was a video that I would learn something. This guy knows and knows how to explain the fine working details. I'm one of those people that has to fully know why I'm doing something before I will use it even though it's a popular test Brandon breaks it down
Excellent Video !
I always use the relative compression test. Quick and accurate test. Most important time !!
Nice job Brandon. Complete explanation without wasted time like so many other TH-cam posters, including professionals. I am retired from 45 years as a technician and love to keep up with what is going on in the trade.
I appreciate you taking the time to watch and for your feedback
Love Brandon's teaching style!
He's a rockstar indeed. I would recommend yall to attend a class of his live! One of the best in the industry in my opinion - Brian Culotta
A million thanks for all of the feedback. Thank you all for investing the time to watch.
To answer a few questions, the RC Test, monitoring for voltage-drop is almost as accurate as current measurement. The difference in reliability is minimal.
I recommend applying this test to a known-good vehicle. Then, try removing a spark plug (to create low-compression in one cylinder) and repeat the test. There is NO BETTER WAY TO LEARN this valuable technique! I use it EVERYDAY 👍
No, thank you for taking the time to teach us. As someone else mentioned, I thought a RC test could only be performed with an amp clamp. Have an awesome year!
Hi Brandon
I am motor nechanic for over 50 odd years (15 years in Europe, rest here in Adelaide, South Australia. Still have opportunity to learn a lot. Thanks for posting it. Time watching new techniques is time well spend.
George - QQMR
Wow, my Jeep made it into the video LOL What a freaking amazing time with you guys! Can't wait to do it again!Brandon, great job on that video.
Thought that was you in the background.
I am learning so much off this guy. Cant say i can keep up that easy , so i watch the video a few times for my slow brain. Fantastic explanations , very impressed! Thank you
I was at a shop for a different problem and I overheard another mechanic was bitching about removing the intake to do a compression test so I did a RC test and found he didn't have a compression problem he was so impressed he gave me $100 dollar bill!!
Great job Brandon
PHENOMENAL!!!
So five years later i hit on this vlog, if that garage is yours and u own it top man, if that garage aint yours and you work there they aint paying you enough and your talent is wasted, great vlog great explanation , you have a great easy way to explain things that is instantly understandable, brilliant vlog...
Brandon, Keith & Ivan all together in one workshop - lucky customers :)
It's funny watching Keith run back and forth in the back...lol.
Good testing/procedure and as usual, "knowledge is power" and being efficient in this field is very KEY! Time management guys.
This was so professional , that Brandon even said AFFIX . I like it 💙
Super helpful ! Wow ! Such an outstanding tutorial ! Extraordinary detail !! You provide precise coaching cues for us to do the procedure ; AND , include all the other pertinent information - namely, the “who , what , where, when , why, and how !! I’m learning lots from you ! Thanks mate !!
🙌🏼
An extremely well made video! Extremely professional and very well spoken! You are an asset to your professional, Brandon. All you NY guys (Eric O., Keith, Eric and more) are top-tier professionals! I am now a subscriber!
Thank God for all of you guys out there sharing your knowledge and experience with all of us!!!!
Excellent demonstration Brandon, thanks tbt for putting this info out there. It took me months to prove to my shop that rc is trustworthy. Id have to do it conventional just for them to feel comfortable with rc testing. Now they don't bother, i print the waveform, and they don't question, ever 🤣
Another excellent demonstration on using the scope to do a relative compression test.
Finally the man behind the articles. lol
Read some of your stuff on motor age magazine and its always a pleasure.
Thank You Brandon for taking the time to teach and helping out the industry..
Thank You,
I can’t tell you how much we appreciate the feedback. It’s a good feeling, to know my articles are helpful.
Great job. Brandon is knocking another diagnostic strategy out of the park with a wealth of information.
Great video guys
Cool video! I never thought to use voltage drop for a relative compression test! I appreciate the clear and concise explanation! Thanks!
I had no idea you could do a relative compression test with a scope without an amp clamp! Great stuff right here - thanks for that one, Brandon! AC coupling right at the battery - I'd have never thought of that. 👍👍
Noticed Keith and Ivan making cameos in the background there - now that's a garage people will want to bring their modern, computer-controlled problem-children to. 😎
Happy New Year guys! 🍻
Quality video...everything explained well. I only recently realised that you could use voltage instead of ampage...thanks for showing us
This guy is a great teacher and very precise
I would let him work on my trucks anytime. And I’m Looking for more vids by him. Hope he has several
Kevin, thanks so much. I work with a great group of guys @Trained By Techs and it’s a tremendous team effort.
We will have plenty more instructional videos to come 👍
Excellent demonstration, good information and very easy to follow
Thanks for taking the time to present this. Great job.
Nice Diagnostic procedure, GREAT way to start off 2019 with Time saving accurate Diagnostics. This is a Perfect way to nail or eliminate one of the funnels I always talk about ( The Engine Integrity Funnel )
Excellent video as always Brandon! The power of the scope cannot be underestimated. Been playing with a pulse sensor recently and all of the opportunities it presents.
Very good presentation, thanks for taking the time!
Thanks so much for the positive feedback. Stay-tuned as we will have another video coming in a few weeks👍
Best I have seen, professional demonstration
The light bulb went off when you moved the cursor to zoom. I have a verus edge and I thought the zoom was useless. Thanks clearing that up !!!
9:50 was my favorite part. Shows Brandon as a true professional
Why what happened?
@@TrainedbyTechs he only quick smirked even though I walked by mooning him . 😏
@@NewLevelAuto 🤣😂🤣
haha he actually did I was there xDDD
Brandon, that was an AWESOME video on compression testing. Now I really want to see a relative compression waveform on your Civic with a 20psi loss on cyl2...would that show up on the scope? Also we have to do a follow-up vid on Keith's van, since it actually DOES have a mechanical engine problem than the relative comp test didn't definitively show :) I have the vacuum Pico waveforms here for reference.
It was so much fun hanging out with you and Chris and Keith on the Island, we should do that again sometime soon! Happy New Year!!
Yep Me too! I definetely want to see a compression waveform from the civic wich has 20 some PSI difference in relation to other cylinders...
Most-definitely...lets pool our collected data and I will do a follow-up video-post
Great video Brandon 😀. Planning on watching your tst webinar 😎
Very well explained as usual. Thanks for taking the time to make it.
Another tip I like to employ that is equally as valuable as AC coupling, is to invert the scope leads on the battery, this will allow it to appear like a conventional RC test with an amp clamp.
L1 Automotive Diagnostics and Programming LLC good tip will try this
I wouldn't, potential for blowing your scope if its connected to ground some how such as when connected to a mains powered laptop as you're effectively creating a short through the scope.
Battery powered not as risky.
Safest bet just use the invert function.
Excellent video Brandon. I see Keith Defazio walking around in the background. 👍
Yes, I had to give him a lollipop just to get him to sit still😆
Great presentation. Great video.
Thank you, James
Awesome video,,,very detailed. Many thanks for sharing your knowledge and taking your time to help others wanting to learn the correct way of using a scope. Big thumbs up....
Thanks Brandon. Had your class at Super Saturday 2018 and I thoroughly enjoyed it!
Thanks for the great explanation and video. Always used the amp clamp but next time I'm going to try AC coupling.
This guy is good! Thanks for taking the time! 👍
Thank you for the video👍👍👍
Keith's walking around a lot in the background, someone get him a coffee! Lol nice video Brandon! Super professional!
Thank you!
Awesomeness! Thank you so much Brandon, I can't afford a new clamp at the moment, I always thought too ya needed to clamp battery wire. Thanks again.
VERY good presentation. I’m Impressed 👍
👍 thanks for sharing! Please keep it up.
Brandon : I appreciate your time and knowledge . There is a company called Auto Ditex in Bulgaria that makes several diagnostic items , including a relative compression tester . It clips to the battery . The test can be unsynched or synched to ID each cylinder . It is a low skill level . I saw Diagnose Dan use it . There is also discussion on Scanner Danners channel . It costs $ 290.00 on E Bay , plus shipping . I don't know if a single channel U Scope from AES Wave can do this . But wouldn't you need the a second channel to synch the cylinders ? Again , thanks for the lesson . Bill .
Bill, this is true. To sync the RC test, a second channel is needed.
Nice video and very well explained. It's a shame you didn't do the relative compression test on the first vehicule. It would have been nice to see if the relative compression test would have caught the weak cylinder that showed up in the conventional test and just how much difference would have shown up on the trace.
Hey Michael,
You bring about a great point. The terminology “relative” obviously referred to how each current-peak relates to the next. Because is inferre s “starter-Load”, minor/normal variations in compression won’t make much of an effect on the current-trace. However, when there is enough of a shift in compression-differential to cause a drivability-symptom, my experience has been that the evidence is clear. Try it yourself, by loosening a single spark plug to simulate compression loss👍
@@brandonsteckler3417
Brandon, I was trying to find out if anyone had ever tied the two tests together. In other words would a 10% reduction in compression over the companion cylinders show up in a relative compression test, OR would it take 20, 30, or 40 percent before you'd see the difference on a relative compression trace? I was looking for the cutoff number?
I would assume it’s based upon the the vertical-resolution of the scope and would also take an accurate/responsive supplemental-voltage support, to maintain the accuracy of the test
SUBSTANTIAL Trained by Techs
Brandon Steckler
Tutorial brilliant video amazing from the start to finish loved it thank you very much Brandon Steckler Trained by Techs
From Nick Ayivor from London England UK 🇬🇧
Great video!!
AC coupling filters out the DC signal portion. I understand using AC coupling when testing AC ripple on an alternator (AC source) to block out the DC voltage to increase the image resolution on a scope.
However I am a bit confused on how AC coupling is working in the video: relative compression case while we are using the starter's voltage drop (DC signal). The starter's commutator strips also generating AC ripple while it's revolving, no?
Can someone dumb it down and explain how this actually works with AC couple/capacitor feature when it comes to relative compression?
Thanks for the reply Mike. AC Coupling will remove the DC from the circuit and simply show the "change" in voltage. Everytime a piston approaches TDC, the voltage will naturally drop due to the load on the circuit. AC coupling allows the scale of the tool to be much smaller (1-2v) which allows the drops in voltage to be more pronounced in appearance. Effectively creating a "zoom" feature.
Brandon you are the man. Thanks for the explanation!
Surely,
Typically we view waveforms as reference to ground.When we view an AC signal, we think of it as one that varies above and below the ground line (meaning positive and negative). This is a true statement but it would be more accurate to say “an AC signal is one that varies above and below the reference point.
When we AC Couple a Waveform, we make the reference point the average point or center of the waveform (not ground). If we then place the scope in a lower voltage range, we can view variations above and below the reference point (the average of Waveform. This technique serves as a ZOOM function. This works well on scopes that don’t possess great zoom capabilities.
Does this make sense?
Fantastic explanation! I'm looking forward to Brandon's classes! Even vocally, he articulates so well! Check out Brandon's article in Dec Motor Age Magazine "The Importance of Asking Why...."
Thanks Cuba , appreciate the support ❤️
With all my respect to your experience
Cylinder Compression test is an accumulative way of testing, some service info specify the number of piston strokes/revolutions to record the reading some do not mention anything, therefore it is essentially an accumulative testing so no matter how many compression strokes you go with, the air pressure inside to combustion chamber, the hose, and the gauge eventually gonna equalize on a definite Psi reading.
Thank you for the great video
I love it when I learn new stuff. Fantastic video! I don't know why, but I just didn't consider voltage drop instead of current. 35 years I've been doing this. Duh-huh. Thank you.
AWESOME! This is exactly why we share! So many have helped us, early in our careers and we wish to pay it forward
Brandon, great video with excellent information hope to see more videos from you, Happy new year and cheeeeers
Thanks for the video.
If you are used to use the current clamp while testing relative compression you might want to invert the trace so the peaks of the signature align with the compression humps.....
Or you can put your positive probe on the engine block and the ground probe on battery negative while you are DC-coupled in the 1 voltrange, makesfor a really good signature
Invert the probes....that is simple and brilliant! Awesome tip. Will try that next time :)
Thank u Brandon. Can't wait to attend ur class in jersey for tst this month. Have a blessed day and a happy new year. All the big dogs in one shop. Wow😃😃😃
AWESOME video ,Brandon, Thank you for the effort to illuminate us all, 🙂👍, what else is there to say except, 'lets go BRANDON' 🤥, BLESS 😇
This is great information. Thanks. Question... Would the traditional compression test work with the schroeder valve removed? I didn't quite understand that.
Awesome video Brandon.
This tech is truly a professional technician. I never even knew that conventional compression tests with the snap on compression testers with shrader valves can cause that... I guess i would've misdiagnosed then...
Very nice Präsentation - thanks for Sharing !
excellent video amigo thank you for you time and explaint
Relative compression test definitely the way to go, I’d love to see a relative compression test on the civic ... great video 👍
Better than that...I challenge you to try it yourself, on a known-good vehicle.
Capture/post and tag me in it...tell us all what the test has shown you 👍
Brandon Steckler I see what you’ve done there and I like it, it shows how professional and committed you guys are to teach us 👍... unfortunately I don’t own a scope but I’m setting some goals for 2019 and a pico scope is one of them hopefully soon ... cheers
You be sure to let us know how we can help you move forward
You are not off the hook yet, though… When you get your scope, I still expect your capture/post 😬
Brandon wow! Invaluable lessons. I got a bit lost with the ac coupler. If you can explain
Thank you Brandon. Good job. Have a blessed and safe New Year to you and your family.
You did a great job explaining the steps while working. Your pretty talented. (Even with Ivan and Keith messing with you, you continued on!
😆..I love those clowns, great friends
I believe on the ATS E Scan Elite , you can do a relative compression test , in SECONDS at the OBD2 connector . As well as a Volumetric Efficiency Test , etc. What about when you have to remove an intake plenum just to gain access , as well as risk breaking plugs , frozen plugs or baked on boots ? This could be done on the Snap On MT-2400 - about 25 years ago , with an amp clamp !
Good job Brandon !
Would about hooking up an amp clamp on the battery and a vacuum transducer on the purge line to check the camshaft and lifter integrity? Thoughts?
Thanks Brandon great video
Definitely a time saver!
Awesome info!! I tried this on a Vantage. I chose lab scope dc volts, 1 volt scale and 2 sec time, then pushed the a/c coupling button. No pattern! Maybe i should chose 4 channel instead of dc volts? Maybe I'm just not recording properly? I a'm watching the vidio for the third time. I will try again tomorrow.
Next day....i got it! Awesome test, thanks!
Awesome! Yes, the test comes in very handy. The best part....it’s quick/easy , yields a ton of data and can be applied to virtually all DC-motor started engines👍
I'm planning to start offering a RC test as part of a marine survey on boats. Plugs can be near impossible to access on some boats. Would you recommend to always do the RC test on a warmed up engine? Or as simple of a test as it is, maybe one test cold and then one hot...Might reveal more info
Thanks, you can clearly see the value in the test. Most-often the faults it reveals can be seen when the engine is cold. However, there could certainly be situation ms that arise where a mechanical fault will surface when an engine comes to operating temp. My advice...test under the conditions the “symptom” is present 👍
This was awesome thank you. I didn’t realize you don’t need an amp clamp just postitve and neg on the batter. What did you have that channel set as?
Thanks for the input and I’m glad we could assist you 👍
Lo interesante es que lo hiciste sin usar una pinza amperometrica al positivo del burro de arranque. Poner en AC el osciloscopio para la medida al borne negativo de bateria. Ingenioso. Felicitaciones
Great job on the video
Wow excellent more vids plz
THANKS, More on the way! Anything you’d like to know more about?
What exactly is ac coupling and in what applications is it used
Awesome video.
Great video! Was a bit distracted with the thought” who does he look like”. Then realized a young Sly Stallone. Yo Adrian😄
great video.thanks
Thank you Brandon Steckler! Very well explained! I'm just wondering if Voltage drop test is as accurate as current drop test since voltage and current have different reaction times (problably not a considerably difference to set a noticeable difference at low cranking RPM tests) Just wondering.
Yes, the vdrop Test will yield you similar results as the amperage-test. Close enough to make a sound determination of a mechanical fault
Voltage drop and current flow are proportional to one another. In fact, You You place the both on the same scope, they are mirror images of one another , just inversely proportional
Hello mr Brandon what would happens with the waveform if the engine has a wet spark plug by oil thanks a lot for an answer
Hi, Great question. The key to successful and efficient diagnostics is understanding the limitation of the tools/tests being utilized. The relative-compression test (voltage-drop or amperage) simply displays the the load placed upon the starter as each piston, in-turn , completes a compression stroke. So long as the cylinder fills/seals similar to the other and has the similar stroke, the load should be the same.
To answer your question, simply having oil on the spark plug means oil consumption is present but not necessarily a loss in compression. Does this make sense ?
Pretty good video;.
Dustin, thanks brother 👍
That dam ambulance/fire truck
Brian Culotta HOW CAN I PURCHASE YOUR TEACHING CLASSES ON VIDEO IF I CAN NOT ATTEND AND THANK YOU FOR YOUR TIME .
Damn, I just cringe thinking about weak hood props and a hood crashing down on a new Snap On Zeus while I'm inside cranking over the starter. I think a quick go -no go relative compression test with volt leads could be done right inside car, off a DLC Line SPI. I'm too lazy to bother hooking to a primary wire of coil for a trigger unless I see a smaller dip somewhere between humps to justify wire piercing for a trigger to determine which one has a compression deficit .
Yes! Thank you for pointing that out. Anywhere there is access to source voltage/Ground can be utilized.
The DLC is a great place to sample, right from the driver’s seat. You make the valid point of capturing a sync only if a fault is detected. It definitely saves time not to find a sync unless necessary.
I appreciate your help, thank you!
Now this is the kind of extra info I love
amazing
Honda with APP held to the floor, does that actually mean throttle held open. I've found some vehicles do not.
APP is a request, not a command. Depending on the software/strategy, the throttle blade mat not open
Thanks for the share.
Brandon good job Amico mio, you have a high ability to transfer information said by a foreigner!!!
Armando, my friend! Thanks for tuning in. We’ll get together one of these days!
Thanks for the feedback!
is that kieth using a bosh broom at 12.53 in the video ? and was ivin there showing him how to use it ? ha ha great video brandon
Wouls have been great to see the labscope on the Honda to see if it picked up the weak cylinder that the conventional test saw. Maybe next time?
You should also add, if you haven't. What happens when you take something apart and something gets damaged.
Jesse, so true. Thanks for bringing that point up👍
I thought that was new level and pine hollow milling around in the back ground. Looks like some serious discussion was going on. Kieth seemed a little agitated.
Lucky shop to have the big guns helping them.
Very good
great video. i'd loose the long hose on that mechanical guage
Thanks for that
easy to grab low hanging fruit..great info
My location only allows me buy an hantek amp clamp and it doesnt close in the battery cable, for luck i see this video
Thanks!!
I think Brandon teaches better than Kieth , that is , he slows his thoughts down so the viewing audience can stay up. Kieth knows his sh&t, but skips a lot of his demonstrations, as he probably saying to himself they (the viewers)should already know this stuff. And no Kieth , I watch everyone of your videos but scratch my gray hair afterwards. lol.
Yeah , I just assume that everyone will get out there and seek the training. Not just the free stuff . But the thousands of dollars worth that I spend every year. The sacrifices and effort that I put into receiving my own training , well the only way to get paid back for those is by fixing cars for a living, not TH-cam. So I'll never spend the time to make very long drawn out videos. There is no benefit. I already lose enough time and money to help where I can for free. Take those moments where you're lost after the video and use that as your incentive to go get some training . Cheers
Keith is an absolutely phenomenal diagnostician. We have to keep in mind that Keith is “working “/running his business” all while sharing his videos with us. It takes a tremendous amount of concentration and thought to get, what you were trying to share, out there for viewers to see.
If Keith took the time to break down every thought, to the most basic point of view, his videos would be hours long, and not as well received.
I appreciate the support and the complement but will remind you I did that video with all of those Fellas , with no time constraint at all. This is why I had the luxury of taking my time to articulate.
Keith is just sharing some interesting observances when he comes across them. most people viewing Keith's channel have some knowledge in this field know what's going on in the video and is more of a guys look what I found out keep this under your hat if you come across this issue on one of these type things.
Exactly that! We all have to make it our duty to actively pursue training