Power Trim Problem - 1978 Mercury 1150 (Tower of power) 115HP

[70sBaha]

Hi everyone, hopefully someone will be able to point me in the right direction.

I've been all through the forums looking for answers but I can't work this problem out and I'm new to boats as this is my first.

I took the boat down to a cottage for a week and we had it anchored in a small bay. One night we were down there and a big storm rolled in and subsequently broke the anchor line and beached the boat. Luckily the beach was sand and there was no real damage except for this:

The drivers seat had spun around and jammed against the trim toggle switch and had held it 'up' all night.
When we got the boat back in the water I tested the trim 'down' and it worked but the trim 'up' would not work.

I looked for relays but couldn't find any. The toggle switch has 4 wires coming from it green, blue, purple, brown and it runs all the way to the hydraulic pump? where they connect.

What should I look for or what is likely the cause of the problem?

Thanks!

 

[Fed]

I'm not sure what switch you have but here's a thread that shows what 'should be' the circuit for your '78.
http://forums.iboats.com/forum/engi...-power-trim-tilt-for-1978-merc-115hp-inline-6

You will need to break out your voltmeter & do some testing to see where you're losing power.

 

[70sBaha]

Thanks for that! Based on the diagram you referenced it must be a burnt out solenoid.

Does it matter which one I replace it with? The one in the diagram looks different to mine.

Mine looks like the first photo below, the second one is like the original in the diagram.





This is my setup.

 

[Fed]

I would only use genuine oem parts.