Outside lower unit will not go up

Chasrein01

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Sep 30, 2024
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Having wiring issues on a 1979 MelHart with the 140 inboard. Outside lower unit will cycle down but not up. I found 2 wires dangling by the unit. The wire are totally frie and I followed them into the main harness. They are spliced into 2 different shades of blue wires. Where do they connect after I install new wires? Are they the up trim solenoid / motor? If so, how do I connect them to the lower unit?
 

alldodge

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Mar 8, 2009
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42,054
Most likely the trim limit switch is the issue. Can you get drive to come up using the trailer buttons?
 

alldodge

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Being a 1979 do you have the 3 button up/down/trailer?
 

Scott06

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Apr 20, 2014
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No I don't. Purchased the boat used.
Not owners manual get the mercruiser shop manuals for your engine and drive serial numbers. If you post the serial numbers people here can confirm which manuals to get. I got mine used off ebay invaluable if you plan to work on your boat
 

Chasrein01

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Sep 30, 2024
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Not owners manual get the mercruiser shop manuals for your engine and drive serial numbers. If you post the serial numbers people here can confirm which manuals to get. I got mine used off ebay invaluable if you plan to work on your boat
It's dark now. I'll post them in the morning.
 

alldodge

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Good then you should have 2 relays and your wiring should be as in pic

Power Trim 2 Solenoid.jpg
 

Chasrein01

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Sep 30, 2024
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Thank you. Also where do I connect the outside wires? Do I have to remove or drop the outer unit?
 

Bondo

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Thank you. Also where do I connect the outside wires? Do I have to remove or drop the outer unit?
Ayuh,..... jumper 'em,...... right back to the up solenoid if necessary,....
 

kenny nunez

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Jun 20, 2017
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3,290
Those outside wires pass through the upper part of the gimbal housing. They are held in place with two 1/4” 20 bolts that are going to break off.
If you do not have a trim gauge just cut those wires off. You should be used to how your boat feels when trimming it in or out.
Do like Bondo suggested and save yourself a lot of greif.
 
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