Got my new WPS500 today. Thanks Tom :))
I had a car in the shop, took it out of the case, started using it in 3 minutes. Cool.
Now, help me interpret correctly. I call this a burned valve. What is the correct call?

Thanks. tr

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Thomas Richardson wrote on Sep 19^th, 2011 at 6:06pm:

Now, help me interpret correctly. I call this a burned valve. What is the correct call?

Thomas
If you use the crank sensor along with the compression wave of cylinder 1 it will help you.

The fall of the compression wave indicates a pressure loss, how was its companion cylinder?

Did you use Toms custom probes (bar)?

Hello Thomas,

Congrats on the WPS  [smiley=dance.gif]

What are you working on?

It looks like the peak compression is low for most modern engines and the compression towers are uneven, the air is getting out of the cylinder faster then when compressing.

If you could add a CKP and the ignition sync for the cylinder you are testing that will help quite a bit.

dave

Hello Mick,

DAM your fast!!

[smiley=beer2.gif]

dave

Here is the good cylinder next to #3. It looks pretty good. I am just motivated to get good at this.  thanks. tr

I don't have the custom probe yet. Does it take a secret handshake to get?  :)

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OK, this is a 06 PT cruiser, this is cranking comp. cause the #2 and #3 cyl, you have to pull the intake.

Thomas Richardson wrote on Sep 19^th, 2011 at 7:08pm:

I don't have the custom probe yet. Does it take a secret handshake to get?

Tom will let you know how to get them

This is how we see them after fixing your files but we can’t get an accurate measurement.

Great to compare waves with reference.

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Thomas Richardson wrote on Sep 19^th, 2011 at 6:06pm:

I call this a burned valve. What is the correct call?

I would say the exhaust valve closed too soon on this capture. the piston is still on its way up when the valve closes and the waveform shows a pressure peak.

At least thats how i see it....I could be wrong

Hi Thomas,
one thing I try and do for better valve operation definition in the waveform is to restrict the intake. I use a cork rubbing block if inlet removed. Hard to do if solo though.
darren

daveyK wrote on Sep 19^th, 2011 at 6:40pm:

It looks like the peak compression is low for most modern engines

ooops, I don't know what I was looking at but 178 psi, if the range is correct, looks OK   [smiley=bash.gif]

dave

[edited] the first file was lower at about 81 psi and the second file was around 178 psi.

Where you in the same hole with the same setup, hose, channel options?

Thanks,
dave

Thomas,


Quote:

don't have the custom probe yet. Does it take a secret handshake to get?

Brian emailed our SAE probes to you in a zip file.  Let us know if you cannot find that email and we will resend.

Call if you need assistance with getting them installed.   ;)

Sometimes mail from Autonerdz (and other well meaning folk) gets put into the junkbin by the Windows automatic junk mail checker. So, check your junk bin.

Somehow the email didn't make it? try obeymycar@gmail.com
thanks, tr

Thomas,

Sent them to that email again just now.....

Randy H. wrote on Sep 20^th, 2011 at 12:22am:

I would say the exhaust valve closed too soon on this capture. the piston is still on its way up when the valve closes and the waveform shows a pressure peak.

Randy, are you just looking at the picture in #6?  That picture is the 2 different cylinder captures laid over on themselves.

Woops - I was looking at the picture Mick posted. :-[

In the psdata file it just looks like a sealing issue. :)

Randy H. wrote on Oct 8^th, 2011 at 10:05am:

Woops - I was looking at the picture Mick posted. Embarrassed

I KINDA FIGURED THAT'S WHAT HAPPENED.