trim gauge

[ebauman]

Hello All
I have a 1976 johnson 70hp with power trim model #70EL76D . The trim gauge does not work, the control works fine. I have done some checking and when I connect the purple power line and ground to proper posts the needle goes full down but when I ground sending line to proper post...nothing. Then I took sending line to ground... nothing. I have traced the sending line back to the tilt cylinder all is good. I then took a long piece of wire from the tilt cylinder sender to the gauge, the needle then goes to full up. Am I right in thinking this means the sender in the cylinder is the problem. I have found the sender is replacable if this is indeed the problem or have I missed something
Eric
ps. this is my first post but I have been reading and expanding my knowledge for awhile...... meaning this is a great educational forum

 

[HighTrim]

Re: trim gauge

The trim sender back on the engine is a variable resistance thing. You set your multi meter to measure resistance (ohms). Make sure the battery in the multimeter is good because current is needed for it to measure resistance. Then, you put the multimeter probes on the two sender wires and measure the ohms when the sender is in the full up vs. full down position. Up will be 1 ohm, down 88 ohms.

http://ww2.tflx.com/pdf/trimsy~1.pdf

 

[ebauman]

Re: trim gauge

Hi Chris.
I checked the sender with an ohm meter. It reads 175 both up and down, I guess that means the sender is shot. Eric