[s-cars] Whats a good leak down number for a 20V from 100psi

[Charlie Smith]

Earlier, James Bufkin wrote:
> 
> What's a good leakdown percentage on a 20V at 100 PSI?
> 95? 90? 85?

I've always figured you don't want more than about 5% leakage,
which would be 95% the way you asked the question.

Plus, all cylinders should be pretty close to each other.
You can tell where the leakage is occuring if you listen
either to the open oil filler opening (which is air past 
the rings), from the intake manifold (air past the intake 
valves), or from the exhaust pipe (which is air past the 
exhaust valves).

A leak down test will be much more sensitive than a compression
test, an even 10% leakage from all cylinders just shows general
wear.  All cylinders at 5% except one at 15% or 20% means you've
got a problem ...  listen for it and you will hear the source.

    - Charlie


  Charlie Smith  charlie {at} elektro.cmhnet.org  614-471-1418  
  http://www.elektro.com/~charlie          Columbus Ohio   USA
  http://www.elektro.com/~audi         photos & technical info

  95 S6 Quattro  -  24 PSI, RS2 6 speed, and other features  
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