Much of this material came from a file Ditex (makers of the Viso scope) sent me with a request to render it in better English, since Bulgarian is their native language. I should have given them credit in the video (and I'm giving them credit right now), but I built the Power Point only using that document as a framework. I created some of the graphics from scratch. I might also add that Ditex gave me permission to use their material in my class, but I can't publish the document - you might be able to get a copy from them - they're publishing it somewhere.
Hi McCuistian, nice job on the presentation. Just a quick point. At 8:32, Yes Point 1 is the time when you have maximum pressure in the cylinder but not always the point where the piston is closest to the cylinder head. Think about what would happen if there is large compression leak. It is possible to still have the piston climbing, and be close to the cylinder head, and have pressure dropping. The majority of the time highest pressure = TDC but cannot be taken for granted as being true all the time.
Wow this video is awesome. I think there is a guy bernie thompson who wrote a book on the subject and made software for this type of stuff. I really like your video because i can watch it for quick refreshing. If you dont use it you lose it.
6.7.2018 Long Beach, CA. www.automotivetestsolutions.com "Big Dogs Neighborhood" Even the Laptop Scanner software can Test you CATS by driving around the block.
Hi.., the grafic Same with my grafic on my computer in Real time accuisition data on Internal Combustion Engine 4 stroke in 1993 or abaout 30 years a go.
thanks very informing video.how can i use pressure transducer if there is no access to spark plug without removing the intake manifold.(dodge caravan bank2).
Great overview! Do you have copies of the material out there anywhere? One correction though. Nissan advanced electrical training includes scope use. The measuring interface garbage that works with the factory scan tool and now picos. I keep my scope out all the time and i know a few other deal techs who use them. I think it just comes down to the person and if they are really into accurate diag.
Much of this material came from a file Ditex (makers of the Viso scope) sent me with a request to render it in better English, since Bulgarian is their native language. I should have given them credit in the video (and I'm giving them credit right now), but I built the Power Point only using that document as a framework. I created some of the graphics from scratch. I might also add that Ditex gave me permission to use their material in my class. Here's the link to the material I "Americanized" online: autoditex.com/page/cylinder-pressure-sensor-64-1.html
I don't understand how your statement regarding section 5 could be correct, that if the exhaust valve opens between 170* - 195* after TDC then exhaust timing can be assumed to be correct. I've read in Tim Gilles: Automotive Service that the exhaust valve must open before BDC, which I've heard in other places as well. Also, if a CAM sprocket has 36 teeth, then each took represents 10* of CAM rotation, meaning you could be off one or two teeth and still be within the range you specified. I have a similar question regarding the intake valve opening, which I thought was supposed to open before TDC, but 390* would put it after TDC.
Bob, the numbers you mention are not the valve opening events.These are the degree numbers for the midpoint of the exhaust and intake ramps, different things.
Is this is video form school ? If yes i quite suprised how modern it is.When i was student we learn mainly mechanical part of engines form 90's. Im from Poland
juan rodriguez , I do not agree with you , I have a home made in cylinder pressure sensor , and the waveforms are exactly like the pico transducer sensor, may be somthing is not good with yours.
hi sir, my question is that how on the waveform on the power stroke if both valves are closed how would that line not be lower than the intake stroke because if you are going down on the power stroke it seems if cylinder is closed up you would pull a vacuum and that line would be lower than the intake stroke could you explain that so it makes sense
Joe Clark The power stroke is traveling downwards, after the compression stroke! The spike in pressure is what you see as the pressures in the cylinder rises! After the intake stroke, air is trapped in the cylinder to be compressed! At the end of the compression stroke, is the power stroke, and is the pressure of compression returning to (reducing, or going back down) normal as the piston travels down after the compression stroke! It seems as tho it should be a vacuum, but air is drawn in under the intake stroke, and then is compressed during the compression stroke, at which point on the pattern, the decompression of the power stroke, not power as if the cylinder is producing power, just decompression!
Best explanation of cylinder psi waveforms on yt
This reference video is well worth it to commit to memory. A valuable source for the repair of all engines !!
You got that right, Tom.
Much of this material came from a file Ditex (makers of the Viso scope) sent me with a request to render it in better English, since Bulgarian is their native language. I should have given them credit in the video (and I'm giving them credit right now), but I built the Power Point only using that document as a framework. I created some of the graphics from scratch. I might also add that Ditex gave me permission to use their material in my class, but I can't publish the document - you might be able to get a copy from them - they're publishing it somewhere.
Thank you for putting it all together. I wish I could see your booklet.
Gracias amigo, un saludo desde España
Amazing and very useful explication, thank you
Hi McCuistian, nice job on the presentation. Just a quick point. At 8:32, Yes Point 1 is the time when you have maximum pressure in the cylinder but not always the point where the piston is closest to the cylinder head. Think about what would happen if there is large compression leak. It is possible to still have the piston climbing, and be close to the cylinder head, and have pressure dropping. The majority of the time highest pressure = TDC but cannot be taken for granted as being true all the time.
Rod, this reminds me of “ when tdc is not tdc“ 8--)
thank you very very much you did such a great job
best one to date l1 auto and truck master tech keep them coming
KNOWLEDGEABLE Sir Richard McCuistian
👍
From Nick Ayivor from London England UK 🇬🇧 ⏰️ 22:59PM
Good Evening McCuistian take care and have a great day McCuistian 👍
Great tutorial thank you 👍
From Nick Ayivor from London England UK 🇬🇧
You should never stop learning 😉😉
Very good video! I thank you sir for sharing this valuable information! Thumbs up and subscribed!
excelent master, thanks for share your experiencie and time.
Wow this video is awesome. I think there is a guy bernie thompson who wrote a book on the subject and made software for this type of stuff. I really like your video because i can watch it for quick refreshing. If you dont use it you lose it.
6.7.2018
Long Beach, CA.
www.automotivetestsolutions.com
"Big Dogs Neighborhood"
Even the Laptop Scanner software can Test you CATS by driving around the block.
The booklet states that the pressures at point 3 and span 7 should be around atmospheric pressure - yet the diagram shows 2 different levels.
thank you for this video thank you from Mongolia
Thanks, excellent video, I need understand where axactly begins point number 5.
Hi.., the grafic Same with my grafic on my computer in Real time accuisition data on Internal Combustion Engine 4 stroke in 1993 or abaout 30 years a go.
Great job
EXCELLENT
well explained
Ozzstar 🤓
Heeeeyyyyy what’s up
At 6.20 point A what could cause this?? exhaust valve leak or opening too early maybe?
Yep - exhaust valve not sealing/seating and leaking air.
@@McCuistian thank you
thanks very informing video.how can i use pressure transducer if there is no access to spark plug without removing the intake manifold.(dodge caravan bank2).
Not an incylinder of course but you could use a pulse/piezo sensor in the intake, exhaust or crankcase
Great overview! Do you have copies of the material out there anywhere? One correction though. Nissan advanced electrical training includes scope use. The measuring interface garbage that works with the factory scan tool and now picos. I keep my scope out all the time and i know a few other deal techs who use them. I think it just comes down to the person and if they are really into accurate diag.
Much of this material came from a file Ditex (makers of the Viso scope) sent me with a request to render it in better English, since Bulgarian is their native language. I should have given them credit in the video (and I'm giving them credit right now), but I built the Power Point only using that document as a framework. I created some of the graphics from scratch. I might also add that Ditex gave me permission to use their material in my class. Here's the link to the material I "Americanized" online: autoditex.com/page/cylinder-pressure-sensor-64-1.html
Nice video, is this possible for diesel?
With the right adapter!
I don't understand how your statement regarding section 5 could be correct, that if the exhaust valve opens between 170* - 195* after TDC then exhaust timing can be assumed to be correct. I've read in Tim Gilles: Automotive Service that the exhaust valve must open before BDC, which I've heard in other places as well. Also, if a CAM sprocket has 36 teeth, then each took represents 10* of CAM rotation, meaning you could be off one or two teeth and still be within the range you specified. I have a similar question regarding the intake valve opening, which I thought was supposed to open before TDC, but 390* would put it after TDC.
Bob, the numbers you mention are not the valve opening events.These are the degree numbers for the midpoint of the exhaust and intake ramps, different things.
Is this is video form school ? If yes i quite suprised how modern it is.When i was student we learn mainly mechanical part of engines form 90's. Im from Poland
Yes sir I taught this lesson in my classroom when I was still teaching before I retired. Glad to have you watching from Poland!!
i wuld like to have one of those books
PDF is at bottom
home made pressure transducer do not read vacuum so it looks different than Piezo type.
juan rodriguez , I do not agree with you , I have a home made in cylinder pressure sensor , and the waveforms are exactly like the pico transducer sensor, may be somthing is not good with yours.
hi sir, my question is that how on the waveform on the power stroke if both valves are closed how would that line not be lower than the intake stroke because if you are going down on the power stroke it seems if cylinder is closed up you would pull a vacuum and that line would be lower than the intake stroke could you explain that so it makes sense
Joe Clark The power stroke is traveling downwards, after the compression stroke! The spike in pressure is what you see as the pressures in the cylinder rises! After the intake stroke, air is trapped in the cylinder to be compressed! At the end of the compression stroke, is the power stroke, and is the pressure of compression returning to (reducing, or going back down) normal as the piston travels down after the compression stroke! It seems as tho it should be a vacuum, but air is drawn in under the intake stroke, and then is compressed during the compression stroke, at which point on the pattern, the decompression of the power stroke, not power as if the cylinder is producing power, just decompression!
It helps if you look at the patterns in terms of being volume rather than pressure ...
Can you post the booklet
Any way to get a copy of the booklet?
Right here : autoditex.com/cms/user/files/cylinderpressurewaveform.pdf
Where can i get copy of this
autoditex.com/pressure-diagnostic-kit-101.html PDF of original is at bottom of page
Please do not understand me in English. You can make video in Urdu in some way please