Posted by Phil T on 09/05/17 - 5:21 AM
#5
The analog trim gauges work off a mechanical switch on the motor bracket. Typically it is installed on the inside of the motor bracket or installed on the tilt tube.
My F115 had a broken trim indicator stop (installed on the tilt tube).
I would first inspect the wiring connections on the back of the gauge. Next I would find the trim indicator on the engine.
I would expect the gauge to be showing all the way down when the engine is trimmed in completely and 3/4 or more when trimmed out at speed.