leak down test


7 replies to this topic
  • delmas

Posted August 04, 2012 - 02:54 AM

#1

should the motor be warmed up for a leak down test

thanks in advance

  • grayracer513

Posted August 04, 2012 - 10:02 AM

#2

The rings will seal better if it's been run for a while, yes.

  • delmas

Posted August 04, 2012 - 05:18 PM

#3

thanks Grey. You help is much appreciated!

  • mediumdaddy

Posted August 09, 2012 - 06:28 AM

#4

can i ask what a leakdown test is?

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  • grayracer513

Posted August 09, 2012 - 08:09 AM

#5

The engine is locked in place so the piston will not be forced down to BDC, opening a valve, and then air is fed into the cylinder through a manifold with two gauges and a restricted orifice between them. The tool shows what percentage of the air pressure leaks away. It makes diagnosing the sources of compression/combustion losses much simpler since the escape path can be located while it is actually leaking.

http://en.wikipedia....eak-down_tester

  • bryawn

Posted October 29, 2012 - 03:06 PM

#6

What is the best way to hold the piston in place when you crank up the air pressure? Put the bike in gear and hold down the rear brake? Or a big breaker bar on the rotor? Anything else that works well? 50-100 psi can be a lot of force.

  • bryawn

Posted November 02, 2012 - 03:51 PM

#7

bump

  • lumpy790

Posted November 02, 2012 - 08:49 PM

#8

What is the best way to hold the piston in place when you crank up the air pressure? Put the bike in gear and hold down the rear brake? Or a big breaker bar on the rotor? Anything else that works well? 50-100 psi can be a lot of force.


used a 1/2 breaker bar or a ratchet to lock it in place. This way you can listen to find where the leak is.





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