1990 tilt electrical issue 150HP

[rhodyboater]

Hello!
I am a total newbie with outboards, but lots of experience with car engines. I just bought a boat with a 150 yamaha, runs great and passed compression test! But it has an electrical issue with the tilt. This happens both at the throttle and when using both switches on the engine.

The motor moves a few inches up, then stops, wait a few seconds, press switch again and it moves up again a few inches. Need to press switch several times to move all the way up.

Seems to me to be an electrical issue, like a bad relay or ground? I have not checked anything on the motor because I have no idea where these electrical items are.

Is there a step by step troubleshooting chart on this? Or some common electrical issue on this motor.

Want to get this resolved during warm days over the cold winter.

Thanks!

[boats.net]

Remove the trim motor wires from trim relay, connect trim motor wires to 12 volt battery to see if motor works, blue to positive/green to neg trims up, green to pos./blue to neg. trims down.

[rhodyboater]

UPDATE on tilt

Hi

I think its the motor but I am asking for any input.

I checked the tilt and relay today, same issue with switch at helm and at the outboard switches.

Here is the issue:

You hit the switch, hear the tilt relay click, the outboard rises a few seconds and stops...try and use switch nothing...THEN wait, do nothing, a few seconds later I heard a second click from somewhere else (not the relay) and you can press the switch and the outboard rises again a few seconds. I bypassed the relay, same thing, same noise..

I was puzzled about this second delayed noise, I didn't seem to be coming from the outboard. I then realized it was coming from the tilt motor!

So now I know, you hit the switch, hear the relay click, outboard moves up/down a few seconds, tilt motor makes a click noise and everything stops. Pressing switch does nothing.. Wait a few seconds, tilt motor makes a click noise and then you can press tilt button again, and it works for a few seconds again..

So I assume the tilt motor is bad and needs replacing? If so, is this hard? Would hate to have to deal with bleeding freezing hydraulic fluid.

Thanks!

[rodbolt17]

if this is happening with the tilt motor wires dissconected from the relay and taken directly to a battery source, then most likly its the thermal reset device in the motor.
could be a bad device.bad motor or something is binding stalling the motor.

[rhodyboater]

Well, I bypassed the relay one wire at a time, both were not off. But I bypassed with a direct battery with both wires, same problem, same click noise at motor. Yes, it certainly seems like a tripping of an internal thermal switch in the motor itself. I don't think anything is binding, all looks pretty good and sounds fine when operating.

So, I guess I should replace the motor?? Any tips or suggestions or instructions?

[boats.net]

Sounds like you need to replace trim motor but by jumping trim relay and not disconnecting wires you may have damaged trim relay as well.

[rhodyboater]

Do I have to remove the entire trim assemmbly to get to the trim motor??

Hi!

I disconnected the wire and jumped it. Just one at a time. I don't think I damaged the relay. It ran the same after I reassembled.

Do I have to remove the entire trim assemmbly to get to the trim motor?? If so, any tips or instructions?

I have read some posts that seem to suggest this, ***!

[boats.net]

Can take trim unit loose from transom bracket and tilt forward enough to get trim motor off unless bolts are froze up from corrosion, then may have to remove trim unit.