Power Trim Electrical Mercruiser 120

[StarLiner]

First boat toy, 1978 Renken with a Mercruiser 120 I/O. There are 2 prs of wires leading from trim control/pump to outdrive/trim limit switches. These are located on each side of the gimbal housing. Trim works fine raising and lowering. Looking around in the motor compartment, noted these 2 pairs of wires are extremely corroded and no longer connected. I do not see any prior owner reroute repairs. I am confused as to the purpose of these leads. there is no trim indicator on the instrument panel only the trim control. Any help greatly appreciated. I am new to the boat ownership/maintenance world.

 

[flashback]

Re: Power Trim Electrical Mercruiser 120

Starliner, The trim indicator switch is on the starboard side and the trim limit switch is on the port.. do a search of this forum using " trim limit switch" and you will find some posts on this..after its all said and done, if you are not accustomed to using a indicator switch i would not worry about it. the limit switch on the other hand, does have some value, as it will prevent you from raising the drive too far up while the boat is running......good luck

 

[StarLiner]

Re: Power Trim Electrical Mercruiser 120

flashback,<br /><br />thanks for the quick response. I have been reading and studying schematics in my Clymers manual. Starting to understand the wiring at leads, where they start and stop etc. I have owned her for a year. I have stayed mainly at the local lake and same ramp. I have made sure I never start her until we are loaded and the drive is in. It is a visual inspection without the assistance of an indicator. We do beach at one island. I watch the depth finder and start raising. I usually start getting over cautious and just kill the motor and finish raising. Would the existing trim indicator switch be the option to adding an aftermarket guage? As mentioned, there is nothing on the panel now. Maybe I will save the luxuries for that new(er) ride some day. FYI, the original power trim control is a 3 button unit mounted to the left of the wheel. I would not know how to act with one mounted on the shifter. Docking is like driving a standard transmission, talking on a cell and turning all at once(not enough hands). She still is a blast for the boys and I.

 

[StarLiner]

Re: Power Trim Electrical Mercruiser 120

Another question?<br /><br />If the limit swicth connects electrically to the power trim control. Where would the trim indicator switch connect? Sounds stupid but as mentioned, there is no dash trim indicator. I do have 2 sets of wires to the limit switch and to the indicator. The wires to the indicator have corroded completely away except for what passes through the transom. I did not see where these would connect inside the boat. any more info?

 

[flashback]

Re: Power Trim Electrical Mercruiser 120

just a guess, but possibly the out drive units all come out of the box with both switches, then the boat manufacturer chooses to use them or not.. in your case, the indicator may never have been wired to anything.....

 

[AdmiralQ]

Re: Power Trim Electrical Mercruiser 120

I had the same issue. Got the trim sending unit, no gauge on the dash. I'm going to be adding a trim gauge this spring. The outdrives come from the manufacturer with the sensor and wiring, the boat manufacturer just chose not to include a trim gauge as part of the instrumentation package.

 

[Bondo]

Re: Power Trim Electrical Mercruiser 120

Oh Ya, be prepared for a Looonng day fishing those wires through the outdrive..... the gimbal has to be split to do it... you may as well change out all your bellows while you're there....<br />i saved the frustration,+ extra grey hairs... i drive my boat by "Feel"... don't need a gauge.... for launch, or retrieve, or beaching... i drilled,+ tapped a hole to fit an auto antenna right on the back of my outdrive, by the hole to access the trimtab bolt.... if i can see it, i'm getting close to the "trim limit"... if i see alot of it... it's in trailertilt....<br /><br />to get away from your 3 button control.... i found a unit at West Marine that looks like the signal light switch in your car.... turn right, the outdrive goes Up.... turn left, the outdrive goes Down....<br /><br />Good Luck.....