Tilt and trim problem 1996 150HP

[marksmanking]

1996 Merc 150 Offshore- I started having intermittent problem with tilt and trim several weeks ago. When it would go out, it always started working after a few minute wait. This weekend rode out to islands, no problem all day. Back at ramp, motor would not tilt up to retrieve. Finally got motor up, at home trimed down to flush and then nothing. Neither control switch or motor switch would work. I had to release manually to raise enough to back boat over curb into yard. Last night a buddy and I looked at it. We disconnected the leads from the relays going to the pump motor. We got 12 volts coming from the two relays, up and down. We were able to make pump motor work by hooking leads coming from the tilt motor to a 12 volt battery charger and could tilt up and down by reversing leads. We ran it on a spare battery and also on the boat battery by using jumper cables to tilt motor leads. But it would not run by reattaching leads to relay wires even though it showed 12 volts coming from relays on the meter. When we ran the motor on charger or from other battery, the 2 wires going to tilt motor got extremely hot, almost to the point of melting insulation. Is the tilt motor almost fried, having to pull enough amps to heat the wires, but not enough to run off power coming from relays? I'm stumped.