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Compression test - help please

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Old Aug 3, 2010 | 10:28 AM
  #1  
Synjn's Avatar
Synjn
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Default Compression test - help please

I have the plugs for cylinders 1, 3, and 5 out and want to do a compression test. I've never performed one on this car so I just want to make sure I do it right.
Can anyone walk me through this? Which connectors to disconnect? Any tips, like dropping a bit of oil down the cylinder? What numbers I should expect? What should the top of my cylinder look like? Plugs look like etc...A simple rundown would be much appreciated.

Surprised there isn't a DYI for this.

Thanks in advance
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Old Aug 3, 2010 | 10:38 AM
  #2  
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1- Pull the fuel pump fuse in the fuse box under the cowl cover
2-get all the spark plugs out
3-get a pen and paper to record what readings you get from what cylinder
4-get a jumper box or battery charger on the battery ( if you start to drain your battery you'll lose cranking speed and your readings will differ )
5-Test each cylinder in order
6-Install the tester in the spark plug hole and have a buddy crank on the engine until the pressure on the gauge stops bumping up. Shouldn't take more than 10-12 revs.

Final compression test numbers are going to differ depending on your build, what your compression ratio is, type of cams you have etc. The biggest thing to look for right away is that your lowest cylinder is not more than 10-15psi different from your highest.

Go forth, and report your findings.
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Old Aug 3, 2010 | 11:13 AM
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Synjn
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Originally Posted by Brett@AwesomeZ
1- Pull the fuel pump fuse in the fuse box under the cowl cover
2-get all the spark plugs out
3-get a pen and paper to record what readings you get from what cylinder
4-get a jumper box or battery charger on the battery ( if you start to drain your battery you'll lose cranking speed and your readings will differ )
5-Test each cylinder in order
6-Install the tester in the spark plug hole and have a buddy crank on the engine until the pressure on the gauge stops bumping up. Shouldn't take more than 10-12 revs.

Final compression test numbers are going to differ depending on your build, what your compression ratio is, type of cams you have etc. The biggest thing to look for right away is that your lowest cylinder is not more than 10-15psi different from your highest.

Go forth, and report your findings.

Thank you very much!

Is it normal to have this oil around the outer rim like this?


Last edited by Synjn; Aug 3, 2010 at 11:54 AM.
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Old Aug 3, 2010 | 11:15 AM
  #4  
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From: Houston, TX
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No sweat. Let us know how your numbers come out.
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