What is the proper orifice size for a differential tester?
Thanks for your question. The proper size of the orifice depends on the
size of the engine being tested. Specifications for the orifice are
outlined in the current version of Advisory Circular 43.13-1B in paragraph
For your reference:
For an engine cylinder having less than a 5.00-inch bore; 0.040-inch orifice
diameter; .250 inch long; and a 60-degree approach angle.
For an engine cylinder with 5.00 inch bore and over: 0.060 inch orifice
diameter, .250 inch long, 60 degree approach angle.
The A.C. also states the indicated failure should be at a reading of
back to index
Have a small aircraft
problem you can't solve? Click below
to send the
Send mail to firstname.lastname@example.org
questions or comments about this web site.
Copyright © 2007 Little Flyers
Last modified: February 12, 2007