Will Lycoming engines run on UL91?

Many Lycoming engines are approved for operation on UL 91 so long as Lycoming oil additive P/N LW-16702, or a functionally equivalent product such as Aeroshell 15W50, is used.

SeeRobin Service Letter No. 131102 at http://www.ceapr.com/en/support/support-nav.php

AVGAS UL91 can be used in the affected aircraft under the following conditions:

— Verify that the engine has not been modified or altered and meets the specifications of the original type certificate;

—Install on each fuel cap a label from the fuel supplier of make your own placard identifiying that unleaded AVGAS UL91 is acceptable fuel for the aircraft.

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