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mooney265 mooney265 is offline
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Join Date: Sep 2008
Location: New Orleans
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Being a 100psi gauge on the cylinder side of the orifice, if enough air is leaking out of the combustion chamber to make that gauge read say 93 psi because air can't flow through the small orifice in the leakdown tester body fast enough to replace the air leaking out of the cylinder than thats considered 7% leakdown on that cylinder.

Then you listen for hissing air leak with a hose in your ear and the other end in the throttle body, exhaust header or tailpipe, and oil tank or engine case drain plug to figure out if the leak is piston rings, intake, or exhaust valve.



Ok, that makes sense to me.... Does anyone sell a leakdown testing device/tool? I'm sure I can makeup the hose/megaphones you discussed...

Oh, and what's the easiest way to get each cylinder at TDC [or, rotate the crank]? I figure the starter would move the crank in too large of an increment... If I remove all the plugs, could I rotate it at the alternator pulley??
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LIVN80S - - Red '79 Porsche 930 Steel Slant Nose Conversion [in 1987] w. 46k miles 3.3L; 964 Cams; K27HF @ 1.0 BAR, with Garrettson Intercooler; Rarly Zork; CIS Flowtech Fuel Head & BL-WUR.

Last edited by mooney265; 06-19-2010 at 02:36 PM..
Old 06-19-2010, 02:24 PM
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