Mariner 1150 115HP Trim Position Sensor

[Mattakaspeeedy]

Hello,

I have a Mariner 1150 115hp 2 stroke motor with power trim and would like to install a trim gauge on the boat but i dont think the motor i have comes with that option. The serial is USA 4403441.

Can anyone tell me if i am able to put a trim position sensor on it with part number and how if possible ?

 

[jimmbo]

Mariner never called their 115 an 1150. That Serial# checks out as a 1976 Merc 1150, so I don’t know what you have... Trim sensors/senders weren’t introduced until after 83, when the Transom Bracket was changed. If you are creative, I guess you could rig something up to report the trim angle. Most people just rely on how the boat responds to the different angles. I installed a gauge on my 1984 115. Biggest waste of money I spent on that boat.

 

[Mattakaspeeedy]

Ok I’m not a boat expert so be patient with it. Yes it’s a 1976 mariner / Mercury 115hp 2 stroke.
it has a power trim and the trim limit switch on the starboard side transom bracket.

was there ever a option and if not how would I go about installing a aftermarket one or one from a later model
if possible ?

or has anyone done it ?

 

[Texasmark]

Try a google search for something like "Trim sensor installation on 1970's Mercury (or Mariner)." I think I have stumbled across some Rue Goldberg rigs years back, in passing.....didn't pay much attention to contents as I wasn't interested in the subject at the time. I have one on my 2002 115 ELPT Merc. Know nothing but it's a disc about 2" in dia, ⅜" thick, 2 wires and is mounted to the mid section up front and fits inside the transom bracket rear arms when the engine is vertical. It's visible on the Starboard "side" of the midsection and I think that "side" mounting is necessary for it to function if it is what I suspect........really what else could it be to sense an angle change electrically in a small instrument sensor?

Trying to figure out the operation, what would sense vertical position with 2 wires and my best guess is that it has a rheostat (2 wire variable resistor) that has a fixed resistive element with a pool of Mercury acting as the variable arm with one lead sticking in the pool. As the engine is rotated, the mercury moves up and down the resistive element changing the resistance which changes the deflection of the dashboard trim gauge. Works really well and very repeatable.

I don't see installing one on an engine being much of a problem. Merc or Faria Beede Instruments (what I have) ought to have the parts online.

 

[Mattakaspeeedy]

Can someone tell me what this is ? It’s in the left hand side of the transom bracket and looks like a rod or something is meant to go in there and a little black cover thing just above it.
on the right side is the same except for the little black cover.
is this possibly where a trim position sensor would be mounted ?