Mercruiser trim/tilt wiring

[rjs65]

I'm putting new Sierra trim limit and trim sender switches on my 1986 Mercruiser 140, outdrive S.N. A477211, transom assembly S.N.
A504155.

The new switches do not have any color coding on them to tell me which connections go where. I assume one wire from each switch goes to ground and the other wire from each switch goes to the two connectors that the original switch wires went to.

I connected the two "hot" wires and the "up" trim switch did not work. The "down" switch worked. I reversed the "hot" wires and the same thing happened. The trailer switch worked in both scenarios.

The manual does not show my switch configuration. I have a single up/down switch on the shifter and below that on the handle is the trailer switch.

How can I figure out which hot wire goes where?

 

[dubs283]

Re: Mercruiser trim/tilt wiring

the trim sender should have one female and one male bullet connector so those will be pretty straightforward

some older ones will have ring terminals, if this is the case you need to try them both ways 50/50 shot there

the trim limit will have two male bullet connectors and it dosen't matter which way they go, and niether of those go to ground, they go to the purple and blue wires in the trim pump wiring assy

once installed and connected you will have to set both the sender and the limit switch

 

[stonyloam]

Re: Mercruiser trim/tilt wiring

For the trim limit switch, look for connectors with a purple/white wire and two blue/white wires. Polarity is not important. Adjust the TL switch to give a measurement of 21 3/4 inches (+- 1/4 inch) center to center on the trim cylinder bolts.

 

[rjs65]

Re: Mercruiser trim/tilt wiring

Thanks for the help, but now that I've connected the trim limit wires to the purple and blue wires, I still have the same problem as mentioned in my original post.

Additional info: My blue/white wire has a tan/white wire in the same connector. Is this normal? Also, I only have the two empty connectors, which are now occupied by the trim limit switch wires. Where does the other, non-ground, wire from the trim sender go?

 

[stonyloam]

Re: Mercruiser trim/tilt wiring

Need to take a step back here: trim limit first: The trim limit switch shuts off power to the up trim if the outdrive is raised up too high, so lower the outdrive all the way down and try it. If you have a multimeter check the resistance of the trim limit wires with the outdrive down, should be 0 ohms. Back to the b/w wires, one comes from the trailer switch, the other goes to the up solenoid for the trim pump. We know that works. The p/w wire comes from the trim up switch and goes through the trim limit switch back out to the b/w wire to solenoid. If the trim up does not work with the outdrive down, try this: disconnect the trim limit wires and jumper between the p/w connector and the b/w connector the trim up button should work. If it does your control switch is OK and your trim limit switch is WAY out of adjustment. Come back if you have a problem.

 

[stonyloam]

Re: Mercruiser trim/tilt wiring

For the position sender, the diagram shows one side to ground, and the other side to a brown/white wire, that goes to the connector, and on up to the trim gauge. Look on the back of the gauge and see if there is a br/w wire there.

 

[rjs65]

Re: Mercruiser trim/tilt wiring

Thanks Terry,

You were right about the trim limit switch. I adjusted it and now the tilt up switch works. I still don't know where the two trim sender wires go. One to ground I assume. The other...?

 

[rjs65]

Re: Mercruiser trim/tilt wiring

There is no brown/white wire on the back of the gauge. Besides ground and the light, there is a solid purple and a purple/white wire. The p/w wire goes to the back, but currently has one of the trim limit wires plugged in to it. I don't seem to have an empty wire for the trim sender wire to plug in to.

 

[stonyloam]

Re: Mercruiser trim/tilt wiring

OK well something is screwed up. The purple white wire in the back should come from the control handle trim up switch, in fact it must if the trim up switch works. Does it work with the ignition switch off?. Here is a wiring diagram that shows the trim position sender: http://www.boatfix.com/merc/Servmanl/13/13E4R2.PDF There should be a brown/white wire there someplace. The sender may also go to a block as indicated here: http://www.mercstuff.com/trima.htm the gauge should be wired as here: http://volkhart.net/Boot/PDF/Trimm.pdf Good luck

 

[rjs65]

Re: Mercruiser trim/tilt wiring

Terry,

I just wanted to thank you for your advice and suggestions. I found a brn/wht wire at the back of the boat that was grounded. I disconnected it from grnd. and plugged the trim sender switch into it. Everything works now.

I don't know where that wire goes or comes from, but since the sender works, I'm happy.

Thanks again,

Ron

 

[stonyloam]

Re: Mercruiser trim/tilt wiring

Glad to be of some help.

 

[bigdan1]

Re: Mercruiser trim/tilt wiring

having similar problem, thanks for sharing experience