Leaking Spark Plug?
 

Has anyone ever experienced a leaking spark plug? While doing some maintenece to my 50 I noticed that if I cover the plug threads with my fingertip and try to roll my engine over the compression substantially higher than when the plug is in place. This seems pretty odd to me as the compression gasket is in place and the plug is tight so there should be no leakage unless it's leaking around the insulator.

The Plug is an NGK CM-6 in a DA-50R.

RE: Leaking Spark Plug?
 

Scott,
The only way to reall tell if the compression is normal is to use a compression gage.

Larry
I am watching you

RE: Leaking Spark Plug?
 

Squirt some WD-40 on the plug and roll the engine through, leaks make bubbles

RE: Leaking Spark Plug?
 

add new gasket and do the test as noted above.
as for "proper compression" don't worry about it
If the engine piston and ring are nice and not scuffed and the engine flips easily and the prop rocks easily - run it

RE: Leaking Spark Plug?
 

Hey - put a new plug in it (~$2) and fly it.....