greetings all: i am considering purchasing a differential compression tester. the tester that most a&p mechanics use is an automotive type? best for me to buy a tester with the .030" orifice? or do the automotive testers,such as Mac and Snap-On, already have the .030" orifice? continental engines is the only engine manufacturer to specify the orifice size? i would like a tester that i could also use on auto engines.what to buy? ....thank you....
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differential compression testers
- Thread starter lawrence
- Start date
az_gila
Well Known Member
Orifice sizes
The choice for aircraft compression checkers is a 0.040 or a 0.060 orifice.
While AC43.13 recommends a 0.060 orifice for cylinders greater than 5 inch diameter (our O-360s and O-320s are just a bit larger than 5 inches), the Lycoming literature states a 0.040 orifice.
Sounds like the automotive ones won't work...
Standard ones (the E2A) are here...
http://www.chiefaircraft.com/airsec/Aircraft/Tools/CompressionTester.html
The larger orifice will make your engine compressions look a lot better...
gil A
The choice for aircraft compression checkers is a 0.040 or a 0.060 orifice.
While AC43.13 recommends a 0.060 orifice for cylinders greater than 5 inch diameter (our O-360s and O-320s are just a bit larger than 5 inches), the Lycoming literature states a 0.040 orifice.
Sounds like the automotive ones won't work...
Standard ones (the E2A) are here...
http://www.chiefaircraft.com/airsec/Aircraft/Tools/CompressionTester.html
The larger orifice will make your engine compressions look a lot better...
gil A
