Jumped timing chain ID with a scope

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ScannerDanner
OneWave
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Posts: 43
Joined: Thu Feb 23, 2012 4:28 pm

Re: Jumped timing chain ID with a scope

Post by ScannerDanner »

Hey guys, I took some more captures of this car today and I plugged in some numbers that Mick from iATN shared with me. I think there are some variables with the CKP sensor as far as cursor placement, but I haven't done enough of this yet to contribute any more right now.
I did pull the valve cover off today to expose the chain and it is super sloppy! So this was a good call. I will take some digital photos for you guys tomorrow.
So check out the pics. I will include the two pico files as well. One during idle the other during cranking.
The image files 1-7 are during idle and 8-11 are during cranking
I am still not 100% sure on my cursor placement and you will see in images 6 and 7 (zoomed in pics at idle) that cursor placement changes everything. You will also notice the valve timing is different during a crank. I believe this is because the chain is so sloppy.
Idle
Idle
Idle
Idle
Idle
Idle
Idle
Idle
Idle
Idle
Idle zoomed
Idle zoomed
Idle zoomed
Idle zoomed
Cranking
Cranking
Cranking
Cranking
Cranking
Cranking
Cranking
Cranking

ScannerDanner
OneWave
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Posts: 43
Joined: Thu Feb 23, 2012 4:28 pm

Re: Jumped timing chain ID with a scope

Post by ScannerDanner »

a.psdata
Idle
(1.74 MiB) Downloaded 638 times
Here is the original pico file at idle

Martyn
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Location: Cambridgeshire

Re: Jumped timing chain ID with a scope

Post by Martyn »

I have added the pictures to the earlier post :)
Martyn
Technical Support Manager

ScannerDanner
OneWave
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Joined: Thu Feb 23, 2012 4:28 pm

Re: Jumped timing chain ID with a scope

Post by ScannerDanner »

Ok I don't know if anyone is still following thread but here it goes anyway. I believe that bad information is worse than no information at all. One of the things that I always try to do when taught something new is to test the theory and learn all of the variables. I believe that my previous captures where I used the CKP sensor to ID TDC and BDC in the waveforms was wrong or I am just too new to this and placed my EVO and IVC cursors in the wrong place. It was a jumped chain for sure but the numbers didn't match up to what I saw with the chain. The intake chain was a full two links off (4 teeth) and the exhaust was a full link off (2 teeth). In the pictures I posted the exhaust valve timing seemed to be more off than the intake.
So today I took some known good captures of a 2004 ECOTECH 2.2 engine (same engine code as the 2006 with the jumped chain). I applied the same measurements to see if we could in fact rely on the CKP signal to determine TDC. What I found was that we either cannot, or I placed my cursors for valve timing in the wrong place. I just didn't want anyone to use this method if it doesn't work. Here are the known good engine pics. You will find that these numbers are different from the jumped chain but still not to spec using this method.
Cranking
Cranking
Cranking
Cranking
Cranking
Cranking
Cranking
Cranking
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
Here are the original Pico files
a.psdata
Cranking
(4.46 MiB) Downloaded 426 times
b.psdata
Cranking
(4.99 MiB) Downloaded 521 times
a.psdata
Running
(4.12 MiB) Downloaded 442 times
b.psdata
Running
(4.48 MiB) Downloaded 455 times
c.psdata
Running
(4.94 MiB) Downloaded 448 times
d.psdata
Running
(3.74 MiB) Downloaded 449 times

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Robski
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Re: Jumped timing chain ID with a scope

Post by Robski »

still following .............

Mick
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Joined: Sun Feb 26, 2012 7:59 pm

Re: Jumped timing chain ID with a scope

Post by Mick »

I had to cut the above to be able to post this
ScannerDanner wrote:I just didn't want any one to use this method if it doesn't work.
So after your second vehicle one bad and one known good you are now the authority on pressure waves pretty good going sport.
ScannerDanner wrote:Here are the known good engine pics.
If only I could master posting images to this forum

ScannerDanner wrote:You will find that these numbers are different from the jumped chain but still not to spec using this method.
That is absolutely wrong the intake of the known good waves intake closing lines up perfectly at 56* ABDC to the crank pulse.

comparison wave intake side
comparison wave intake side
comparison wave intake side
comparison wave exhaust side
comparison wave exhaust side
comparison wave exhaust side

Martyn
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Location: Cambridgeshire

Re: Jumped timing chain ID with a scope

Post by Martyn »

Mick,
Did you get my message about posting ?

Regards,
Martyn
Technical Support Manager

Mick
OneWave
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Joined: Sun Feb 26, 2012 7:59 pm

Re: Jumped timing chain ID with a scope

Post by Mick »

Martyn wrote:Mick,
Did you get my message about posting ?

Regards,
Yes thank you Martyn.
It looks as if I can add images now but I will try to place them into the specific area like you did next time.

ScannerDanner
OneWave
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Joined: Thu Feb 23, 2012 4:28 pm

Re: Jumped timing chain ID with a scope

Post by ScannerDanner »

comparison wave intake side.gif
comparison wave exhaust side
comparison wave exhaust side.gif

Mick, please forgive me as I did not mean to offend you. You have been great at responding to my questions and giving me direction. What I posted on this forum about "bad information", I meant the information that I provided may be bad. I did not mean to imply that your information is bad. While I still have my doubts, I appreciate your contribution to this and truly am just looking for some clarification. When I didn't here from you about whether or not I placed my cursors in the correct location on the original jumped chain pictures that I did (using your formula), I assumed they were correct. So when I applied the same placement of the cursors on the known good engine and found the numbers to be all wrong, this is where my doubts are coming from.
Again I apologize to this board for placing this thread into two different forums as I believe I have created a monster. I was just trying to update this forum as to my findings and my doubts so as to not lead anyone down the wrong path.
Mick in my description I did say that either this method doesn't work OR my cursors where placed in the wrong place.
I am listening to where I went wrong if you are still willing to share.
Either way thanks Mick
-->
Mick wrote:I had to cut the above to be able to post this
ScannerDanner wrote:I just didn't want any one to use this method if it doesn't work.
So after your second vehicle one bad and one known good you are now the authority on pressure waves pretty good going sport.
ScannerDanner wrote:Here are the known good engine pics.
If only I could master posting images to this forum

ScannerDanner wrote:You will find that these numbers are different from the jumped chain but still not to spec using this method.
That is absolutely wrong the intake of the known good waves intake closing lines up perfectly at 56* ABDC to the crank pulse.

comparison wave intake side
comparison wave intake side.gif
comparison wave exhaust side
comparison wave exhaust side.gif

Mick, please forgive me as I did not mean to offend you. You have been great at responding to my questions and giving me direction. What I posted on this forum about "bad information", I meant the information that I provided may be bad. I did not mean to imply that your information is bad. While I still have my doubts, I appreciate your contribution to this and truly am just looking for some clarification. When I didn't here from you about whether or not I placed my cursors in the correct location on the original jumped chain pictures that I did (using your formula), I assumed they were correct. So when I applied the same placement of the cursors on the known good engine and found the numbers to be all wrong, this is where my doubts are coming from.
Again I apologize to this board for placing this thread into two different forums as I believe I have created a monster. I was just trying to update this forum as to my findings and my doubts so as to not lead anyone down the wrong path.
Mick in my description I did say that either this method doesn't work OR my cursors where placed in the wrong place.
I am listening to where I went wrong if you are still willing to share.
Either way thanks Mick