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1988 mercrususer alpha one tilit trim.

S

scokat

New member
the up tilt and trim button on throttle does not work. put new solenoids on, up buttons on throttle do not work. put new reservoir on pump, pump works fine. crossed the solenoid lugs for up and motor raised, and lowers by the down buttons. There is no trailer button on motor. any ideas what to check next.

scott
 
My Alpha did that and it turned out to be a faulty trim sensor on the stern drive. I bypassed it to test and it worked fine. I then had to fit a new sensor though to make it work correctly.
Just a thought!
 
i took the trim sensor(round cap 4 screws) off and cleaned it, made sure if there where good contacts. How do i bypass to see if thats it.
 
at the trim pump is a black round rubber fuse holder with red wires. It supplies power to the buttons that control the solenoids, I
 
ok, i took the diagram for the single unit out to the boat. Checked for 12 volts at each lower and upper lug. where the square (fuse?) is and where the red wire connects to the upper lower lug on the bottom solenoid. There is no fuse inline for the lower red wire. cleaned all the connections. result is goes down fine, but up is still dead, no clicking no nothing. if i cross the upper lug the trim goes right up? is that square box/fuse connected to the lower upper lug/solenoid, a fuse, and if it is bad would it keep the up button from working? But again, there is 12 volt power where the lug contacts to the solenoid. Could there be a bad switch in the throttle at the buttons?
 
jumping 2 and 3 raises the drive and jumping 4 and 5 lowers it, this tell you that you have good power
using a jumper from the battery, touch the small lug with the thin blue/white wire, drive goes up
Touch the jumper to the small lug with the green/white wire, drive goes down. This tells to that the solenoid contacts and solenoid coil are working.
The red wire just above 7 has a inline fuse that goes behind the plug, that same red wire goes to the control handel giving 12v to the blue wire "up" or the green wire (down)
the small black wire coming from the small lugs of the 2 solenoids get connected together AND a wire from there to the mounting bracket where the neg battery cable is connected.
No ground = no relay operation
 
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ok, is the unplugged the control wires at the three prong plug. That looks like this. (|=) bottom right is power, top right is down, left vertical is up. if i jump hot to either up or down, the motor goes up and down. so from that can i say the problem is from the harness plug to the control switch on the throttle?
I cant find a inline fuse anywhere, is it in the plug?
 
Its not the trim switch
Its the trim limit switch...
Find where those wire are near the pump.
The wires are both black coming from the switch.
The wires that come from the control switch meet those two black wires.
Small junction with two black wires and three blue with white stripe and purple with white. Two of the striped wires are joined together at the junction

Unplug all the wires, black from striped and jumper the striped wires.

Now the rocker switch on the control handle will raise and lower the drive all the way up and down. The "trailer" button is not needed any longer as you have bypassed the trim limit switch.
If this works then replace the trim limit switch.
 
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