1978 trim motor issues

bill62

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Jun 25, 2023
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9
I bought a 78 bayliner with 120 mercruiser with trim issues. With the trim unit out of the boat I tested the solenoid. It has one four post solenoid with blue wire to one of the big post and green wire to one of the small post. The pump runs fine from the blue wire but just clicks from the green wire. I put a new solenoid in it and no change. Thanks for viewing this and thanks for any input that can point me in the right direction.
 

alldodge

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Thinking it's the switch panel not making good contact. If it makes contact but not enough to pass sufficient current the solenoid will just click

Red is the Main hot wire. Connect red to Green on the solenoid with a jumper, if it works then its the switch panel


Power Trim 1 Solenoid.jpg
 

bill62

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Joined
Jun 25, 2023
Messages
9
Thinking it's the switch panel not making good contact. If it makes contact but not enough to pass sufficient current the solenoid will just click

Red is the Main hot wire. Connect red to Green on the solenoid with a jumper, if it works then its the switch panel


View attachment 382528
I tried that and it just clicks where the blue turns the motor on for the pump.
 

alldodge

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I tried that and it just clicks where the blue turns the motor on for the pump.
Don't see that happening unless the wires are badly corroded
You can take the 2 wires on the pump and connect one to + and other to - and it will run one way

Swap the wires and it will run the other way

It it does that it's not the pump, its connections or switches
 

bill62

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Jun 25, 2023
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Don't see that happening unless the wires are badly corroded
You can take the 2 wires on the pump and connect one to + and other to - and it will run one way

Swap the wires and it will run the other way

It it does that it's not the pump, its connections or switches
Thanks for the insight. So I touched the blue wire with + and the motor kicked on without touching the - to the green and the same thing for the green wire except it just clicks and motor doesn't kick on
 

04fxdwgi25

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Mar 25, 2022
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Sounds like that 45 year old motor had a pretty good run, but is now ready to retire.
 

froggy1150

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Nov 3, 2017
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843
Do the rams move both directions or are they stuck. Test this.. remove hoses just before rams and put a coupling to both hoses, then test if pump goes both ways. And while hoses are off check for freedom of movement.
 

bill62

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Jun 25, 2023
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9
My boat has a tilt trim motor model 79271A1 and I'm having difficulty finding a replacement. Anyone have any idea...lol thanks
 

04fxdwgi25

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Mar 25, 2022
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537
2 wire or 3 wire motor?
Check ebay, they have both

Or, you could update with the newer, more reliable style.
 
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