mercury power trim short curcuit

[matthewp133]

i have a 1976 mercury 1150 inline six cyl that i recently converted from a manual trim to a power trim with a 3 wire motor setup from a 87' mercury 150hp, the problem is that the trim will only work when the engine battery cable ground is disconnected ( i have the trim wiring set up on it's on power and ground circuit from the battery) when the engine ground is connected to the battery with the trim battery power and ground it shorts out the trim when the switch is placed up or down (not in neutral, the relay will click and the motor tries to move but burns up the relay or wiring. any help would be greatly appreciated.....thanks!

[Bruster]

Are you using a relays or solenoids? If you have a 3 wire trim motor you need to wire it to run with solenoids.

i have a 1976 mercury 1150 inline six cyl that i recently converted from a manual trim to a power trim with a 3 wire motor setup from a 87' mercury 150hp, the problem is that the trim will only work when the engine battery cable ground is disconnected ( i have the trim wiring set up on it's on power and ground circuit from the battery) when the engine ground is connected to the battery with the trim battery power and ground it shorts out the trim when the switch is placed up or down (not in neutral, the relay will click and the motor tries to move but burns up the relay or wiring. any help would be greatly appreciated.....thanks!

[transomstand]

Should be wired like this

[matthewp133]

the wiring is correct, the only thing that makes sense to me is that the trim motor has an internal short to ground because it works when the case is not grounded and burns up when it is grounded, is this a common problem?

[transomstand]

I've not seen that type of problem discussed here, so I would have to say it's not a common problem.

[matthewp133]

thanks for the help, just replaced the electric trim motor and everything works great! I took the old motor apart and the stator was shorted to the case.