Run up

[James Zimmerman]

Someone asked what rpm to do a run up at. My Continental operator's handbook for A and C series engines from A-50 thru C-85-12 says "Magnetos- operate with full throttle on each magneto separately. From full throttle R.P.M. the drop should not be more than 75 R.P.M." My Cessna manual for the 0-200 says "Magnetos 1700. 75 R.P.M. maximum differential between magnetos. Drop not to exceed 150 R.P.M. on either magneto. The older Cessna manuals for the C-150 do not state the 150 drop on either magneto.                   Jim Ercoupe N99456 Lake Elmo MN.