>
> ...During our annual inspections we have been
> taking the cylinder compressions using an automotive
> compression tester. The first two inpections found the
> compression to be about 180 psi per cylinder. during the
> last inspection (about 10 months ago) the compression
> readings went up about 15-20 psi.
There's many variables in that test, but not in the differential
compression test which is universal in the airplane service biz. That
test gives you something to track trends, and even spot potential
problems coming. Well mostly, but what comes out of an automotive
style test can be more meaningless, more often. The spark-plug hole
fitting can be fabricated from an old spark plug and air-hose male
coupler, but think I saw a Rotax version in some catalogue.
Reg,
Fred F.
|