Re: Trim and Tilt sennding unit
Disconnect the two wires leading to the sending unit. Connect a ohm meter between those two wires. Slowly work the sender's operating lever up and down... when you do this, the ohm meter should register a very smooth reading from a lower reading to a higher reading and vice versa with no hesitation, or gap loss. I don't have the service manual here in front of me so I can not give you the exact ohm measurements.
I prefer to use a analog (needle movement) meter for this test.
