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Motor slowly trimming down under way

Discussion in 'Technical Stuff' started by lakeliving, Aug 25, 2018.

  1. lakeliving

    lakeliving Well-Known Member

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    so I noticed my motor seems to slowly trim down by itself while underway for a while. I’ll have it 3/4 up and after 15 minutes I’ll look down and it will be at 1/2. I’m thinking this isn’t normal but any thoughts?
     
  2. cwag911

    cwag911 Moderator

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    Have you checked the fluid level in the cylinders? Have you noticed any fluid leaks? If no visible leaks then maybe a check valve.
     
    Last edited: Aug 25, 2018
  3. Spoiledrotten

    Spoiledrotten Well-Known Member

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    I might be having the same issue. I’m pretty sure that I keep mine at resting on the trim tabs while sitting in the driveway during adventures. The last couple of times I’ve gone out to give it a hug, the motor is at the bottom position. So maybe it’s not that I left it down.
     
  4. CcanDo

    CcanDo Well-Known Member

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    A couple of thoughts, with the unit tilted down, eliminating hydraulic pressure on the hoses and cylinders, install a gate valve on each hydraulic line, run the unit up, disconnect power for safety, close each gate valve for an extended time.

    The test is for determining if the leak down is occurring because of an internal cylinder leak or else where in the system. Subject to the cylinder leaking internally, new internal seals will then be installed.

    Subject to the cylinders NOT leaking internally, contact the pump vendor to learn if there is a procedure for testing check valves and pressure holding.
     
  5. lakeliving

    lakeliving Well-Known Member

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    Figured I'd close the loop on this. Turns out the manual bleed that allows you to lower the outboard if you lose power was a little loose allowing it to slowly go down. I tightened the screw on the side of the unit and there have been no issues since. I like easy fixes like this.
     
  6. Mike31406

    Mike31406 Well-Known Member

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    Lakeliving any chance you could take a picture of this screw?
     
  7. lakeliving

    lakeliving Well-Known Member

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    C538C079-3520-4BE6-8A68-5D0E73DBD8F1.jpeg Not mine but this is what it looks like. Mines on the port side.
     
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  8. M Jay Farr

    M Jay Farr Well-Known Member

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    A number of posts refer to trim tabs? What do these look like?
     
  9. lakeliving

    lakeliving Well-Known Member

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    I'm thinking that is reference to the two smaller rams that control trim, not the big one that tilts the motor all the way up.
     

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