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Join Date: Feb 2006
Location: Toronto
Posts: 10
Compression test following rebuild

I have rebuild a 2.4CIS with 2.2E pistons/cylinders, Rebuild heads, E spec Cam. I am in the process of timing the cams which are set to 3.0/3.3mm. Out of curiosity I took my compression tool and turned the motor around by hand, to see what the compression is: it read ( 30 psi ). Is this normal as things have to 'seat'? Or is it because I am spinning the motor around by hand or do i have something wrong? From reading the various books suggested on this sight and other posting regarding the timing. I set the timing such that at TDC, setting dial indicator to '0', rotating the crank 360 degrees: my dial indicator is now at ( negative 3.1mm ). Help me please understand.

Old 08-19-2007, 10:24 AM
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Join Date: Jun 2003
Location: Camarillo, Ca.
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Don't even waste your time with a compression test at this point.

A. Ring have not set

B. engine need both oil and a starter to get a proper reading.

Your dial indicator either moved, was not zeroed properly, or your lash was not set correctly. Also, make sure that the dial indicator is not impeaded by anything through out it's movement.
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Old 08-19-2007, 11:04 AM
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My understanding of the timing of these motors is new. I put the z1 mark to TDC, my camshaft 'dot' marks to 12:00 o'clock, set the dial indicator to 'zero' on the intake valve for #1 cylinder, rotated the crankshaft clockwise 360 degrees, and the intake valve at this point is opening and the dial indicator turns counter clockwise for a total counter clockwise length of 3.1mm. Is this not correct? Thank you for your response.

Last edited by cheapporsche; 08-19-2007 at 12:20 PM..
Old 08-19-2007, 12:18 PM
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Sorry, missunderstood. What you have stated is correct. I thought that the dial indicator did not go back to zero...I need to read slower You are looking for valve lift which will be a negative number (dial indicator reading a greater distance).

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Burnham Performance
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Old 08-19-2007, 12:58 PM
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