Any guesses on Trim wire configuration? Lt blue, blue, red, green.

MassillonBuckeye

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Any ideas on #4 and that yellow jumper? Thats exactly how I got it a few weeks ago. Trim up and down both work fine from multiple locations on the boat(bow, transom, console controls) so that Lt blue is trim UP. Theres a bit of a tape wad at the trim pump and I'm half afraid to dig into it since everything is working. But these wires aren't being used yet connected to a push switch. I thought it was a disconnected horn at first until I saw the blue running back with the rest of the trim wiring.

Motor is a 1978 Merc 700(70HP, 3cyl) ser# 4875*** Starcraft boat. Thanks in advance!
 

Chris1956

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

Doesn't look like factory work to me. Mercs of that era had only one trim control panel. Maybe the PO wired in multiple switches, hence the extra wiring? Factory trim wiring is blue for up, green for down, red for power, black for ground and purple for bypassing the trim limit switch
 

MassillonBuckeye

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

Doesn't look like factory work to me. Mercs of that era had only one trim control panel. Maybe the PO wired in multiple switches, hence the extra wiring? Factory trim wiring is blue for up, green for down, red for power, black for ground and purple for bypassing the trim limit switch

I gotcha. Was wondering about a "trailering" feature or something. Because it looks like this was jumpered into the other trim switches. And the dark blue does run back to the trim pump. I guess I'll have to cut the tape off near the pump to be sure.. See what its tied into back there. Thank you for the reply. Anyone else care to venture a guess? Or seen this before?
 

CharlieB

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

The way Yellow is used to energize the light blue switch leads me to think the dark blue switch is bad, that the PO attempted to directly power the Trailer position Dark Blue wire.

I also suspect you will find any trim limit switch on the drive are by-passed and the Up switches will raise the drive fully.
 

RRitt

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

i wouldn't mess with it. When I did get a round tuit then I would replace it entirely with some modernized trim relays inside the engine. then you can have as many switches and locations as you want with light guage wiring and small fuses. A good relays harness should have an inline fuse and pull power off starter circuit.
 

MassillonBuckeye

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

i wouldn't mess with it. When I did get a round tuit then I would replace it entirely with some modernized trim relays inside the engine. then you can have as many switches and locations as you want with light guage wiring and small fuses. A good relays harness should have an inline fuse and pull power off starter circuit.

Yeah, this is pulling off the house circuit. Could you post an example of what I could use instead? I dont think I follow. I put everything back together last night and its all working fine. I eliminated that switch and taped off that blue wire.
 

MassillonBuckeye

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

The way Yellow is used to energize the light blue switch leads me to think the dark blue switch is bad, that the PO attempted to directly power the Trailer position Dark Blue wire.

I also suspect you will find any trim limit switch on the drive are by-passed and the Up switches will raise the drive fully.

How does Trailering work as opposed to Up?
 

RRitt

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Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

Yeah, this is pulling off the house circuit. Could you post an example of what I could use instead? I dont think I follow. I put everything back together last night and its all working fine. I eliminated that switch and taped off that blue wire.

it is a standard trim wiring harness with 12v 5pin auto-security type relays. You can buy used "2w trim harness" off ebay for johnson, evinrude, force, usmarine, volvo, mercury, mariner, etc. They are all the same. You have to modify them for use with 3w trim motors. If you try to use a 2w relay harness on a 3w motor the result can be smoke and flames because it can create dead shorts across your trim motor windings.

A relay is a remote control switch. Your air conditioner at home uses them so that that little thing on your wall can turn on that huge thin beside your house. How dangerous to run a 60Amp 480V circuit into that tiny little thermostat. So they use relays. Same deal with trim. little skinny control wires from the switch back to the relays. big fat power wires in and out of relay to motors.

you can have as many switches as you want all over the boat. when any one of them provides 12v to the light blue control wire it activates the "up" relay. when green then "down". each switch and wiring needs minimal amps and fusing since it only activates a relay. You could daisy chain 10 of them off a single run of 22awg 3c. the actual power for trim motor is pulled from the starter and protected with a 20-30A inline fuse or breaker. The relays are typically bolted onto the starter bracket. motor ground is typically bolted to the transom clamp or engine block. trim motor green and blue is typically 36", protected with a sheath, and runs directly to relays. the entire relay harness with 2 relays should run you about $30. Any SPDT momentary switch will work. waterproof switches preferred, about $6ea.
 

MassillonBuckeye

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Joined
Jul 26, 2010
Messages
400
Re: Any guesses on Trim wire configuration? Lt blue, blue, red, green.

it is a standard trim wiring harness with 12v 5pin auto-security type relays. You can buy used "2w trim harness" off ebay for johnson, evinrude, force, usmarine, volvo, mercury, mariner, etc. They are all the same. You have to modify them for use with 3w trim motors. If you try to use a 2w relay harness on a 3w motor the result can be smoke and flames because it can create dead shorts across your trim motor windings.

A relay is a remote control switch. Your air conditioner at home uses them so that that little thing on your wall can turn on that huge thin beside your house. How dangerous to run a 60Amp 480V circuit into that tiny little thermostat. So they use relays. Same deal with trim. little skinny control wires from the switch back to the relays. big fat power wires in and out of relay to motors.

you can have as many switches as you want all over the boat. when any one of them provides 12v to the light blue control wire it activates the "up" relay. when green then "down". each switch and wiring needs minimal amps and fusing since it only activates a relay. You could daisy chain 10 of them off a single run of 22awg 3c. the actual power for trim motor is pulled from the starter and protected with a 20-30A inline fuse or breaker. The relays are typically bolted onto the starter bracket. motor ground is typically bolted to the transom clamp or engine block. trim motor green and blue is typically 36", protected with a sheath, and runs directly to relays. the entire relay harness with 2 relays should run you about $30. Any SPDT momentary switch will work. waterproof switches preferred, about $6ea.

Gotcha. I briefly owned a boat with this setup so I am familiar with the relays themselves as I had to replace both. So compared to this system, is it just a matter of safety and running a high amp load around the boat when running the trim motor? "Bolted onto the starter bracket". Theres typically enough room under the cowl to do so? Did you say there's a kit? Do you happen to have a part#? I'm going to do a bit of searching here. I'm OK with the current config because they do have all the trim wiring using 6awg within a nice loom of some sort. Mostly soldered ends as well from what I gathered. What would I stand to gain from switching to relays other than the safety aspect?
 
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