Trim motor for my Mercruiser 470 not working?

Question

The other day the Trim Motor was working fine as it has for the last 15 years. Just 4 days later the Trim Motor is not working. I took a Voltage Tester and tested the hot wire to the Trim Motor Selenoid. I got 13 Volts. When the Trim control are engaged, there is no clicking sound from the Selenoid.

Also there is a little black plastic rectangular box under the Selenoid that has 2 wires. We have very low voltage coming off of the hot wire side. I would clear the connection to this box, but the bolts and wires are fused in rust.

What do I need to do to further test and diagnose this issue?

How can I test to see if the Selenoid is bad?

Can I hot wire the Trim to bypass the Selenoid?

What is that little rectangular block box under the Selenoid?

Thanks

Answer 1

don't hot wire it.  too much amperage.  connect the tester to the small terminal with the green or blue wires.  should be 12 volts when you press the trim switch.  green is down and blue is up.  if no volts, switch problem.  if voltage, solenoid problem.  don't worry about the"box" with the two wires.  also, there is a 20amp in-line fuse right there, you might check it first.  if none of the above...ooohh!  motor!

Answer 2

Do you still have trailer mode working.If yes then there is a good chance your trim limit switch is bad which is located outside on gimbal ring where outdrive is located.. There is one on both sides . When facing back of boat the one on the right is the trim sender which sends the signal to your gauge on dash telling it what position drive is at . The one on the left is your limit which when you trim controls how far the drive comes up in trim .Look for bare or frayed,broken wire back there.

If you want to test it you can find the same wire inside boat near trim pump with push together connectors that plug into a blue /purple wire.Disconnect them and the colored wires take a jumper and tie them together and then see if you have trim.

This eliminates the switch and if it works confirms the switch is bad.

Just remember you can trim this way but the limit wont work and you can end up trimming into trailer position. You never want to run engine with drive all he way up because it will bind the ujoints and they can blow apart.

Trim tilt/sender kits are about $80.00 and not an easy  job