Tilt/Trim Relay constantly failing

[Davie]

If You have the plug in 5 pin relays which it sounds like it from previous posts you have a two wire motor. In the engine tray you will find two bullet connectors on the main cable to
the trim motor. Disconnect the wires and put jump leads from a good battery onto the two cables to the power trim motor. Positive on the Blue will make it go up with neg on the green, reverse the connections and it will go down. Tilt motor up and down and try it. If the motor stops after a few minutes its the motor nothing to do with the relays.

[Adz1984]

Originally Posted by Bobg

If there isn't a problem with the wiring/switch and the UP relay repeatedly fails/burns out, then the next most likely problem is the tilt motor may have shorted windings, or the brushes have started to disintegrate. More power is required to lift the engine UP than down.. With a faulty motor more current will be drawn than the relay specifications, thus burning out the relay contacts.

Unfortunately this requires removing the pump motor and dismantling it to inspect the brushes/commutator. I am not familiar with this engine, so I dont know how easy that would be.

Hi Bobg,

I think you were spot on with it being the tilt motor at fault, after many hours with a meter and lots of swearing, is tested every cable and switch possible. Moved onto the motor itself, decided to take it apart with the help of a service manual I downloaded and the brushes were in a poor state. Took it to my local specialist on Thursday who confirmed its pretty beat it up and the likely cause for blowing the relays. New part on order, keeping everything crossed it turns up tomorrow! Thanks for all your help on this buddy, really appreciate it.

[Adz1984]

Originally Posted by beamishken

I'd agree with bobg on this the fault is downstream of the relay causing an overload on the relay
The up relay will always have more load due to the fact it is lifting
The only other possibility is there is a short towards the switch and it's intermittently running the motor with the engine fully up causing the overload
But I presume you have an isolator which you turn off when leaving the boat? In which case you'd hear the motor trying to run assuming your always within earshot when the isolator is on?
Worth investigating but I'd still favour a fault towards the motor

I do indeed have an isolator and I've never noticed the engine raise on its own! Will ha e to wait and see if the new motor solves my issues

[Bobg]

It seems that the motor is the culprit. I can easily imagine the atmosphere surrounding you whilst you were checking out the system. It must have been XXX rated. For broad minded adults only!.
Welcome to the world of 'Elec-trickery'
There was a day when motors were able to be refurbished. Sadly is is not as common now. I hope the cost of the motor does not require you to re-mortgage the house.
Please let us know what the final outcome is. It will benefit the rest of the community

[Adz1984]

Originally Posted by Bobg

It seems that the motor is the culprit. I can easily imagine the atmosphere surrounding you whilst you were checking out the system. It must have been XXX rated. For broad minded adults only!.
Welcome to the world of 'Elec-trickery'
There was a day when motors were able to be refurbished. Sadly is is not as common now. I hope the cost of the motor does not require you to re-mortgage the house.
Please let us know what the final outcome is. It will benefit the rest of the community

It most certainly was x-rated! My neighbours now think I am completely mad...outside in the rain swearing at a boat

The good news is new motor turned up on Saturday afternoon, after cleaning up the mounts new one was relatively simple to fit, and was nice to be working in the sun. I'm very happy to say the motor is working perfectly and I know have down and up! I plan on testing it a few times over this week as after the last relay change it worked one or twice before failing, but it's looking good thus far! Although annoying I didn't get it done in time to get the boat out in the water on what was a lovely weekend down my way!

[Bobg]

Just one last thought, which I am sure you have addressed, make sure that the motor tilt pins are well greased and the outboard tilts relatively easily by hand.
It is clear sunny day here in Falmouth, but you would not be testing the RIB in 50mph+ winds today. Every ferry service, including a chain ferry has been cancelled.