Subject: RE: leak down test
Author: John Ulrich
Date: Aug 2, 2005, 7:47 PM
Post ID: 1719243787
madr-@earthlink.net wrote:
| I am pretty mec hanical but I have to confess I haved never heard of a leak down test. |
Air is pumped into a cylinder thru the spark plug hole using a fitting.
An air pressure guage is attached to it and I do not remember how many
psi is pumped in....100? Set the piston at TDC.
When pressurized you listen for air escaping. You might hear it blowing
in the exhaust (bad exhaust valve sealing) blowing thru the carb ( bad
intake valve seal) or echoing in the crankcase (rings).
The gauge will tell you how much pressure is escaping. I had 30% leakage
on one side and it whistled like a locomotive horn as the air blew out
the exhaust value.
Later,
JU