Trim Cylinder Internal Leak

[kwoolard]

I had found out why I kept blowing my hydraulic lines on my sterndrive. One of my cylinders was almost siezed up. It had a lot of electrolysis going on inside the cylinder. This was causing a lot of back pressure in my hydraulic system and blowing out all of my weak parts, in this case the original hydraulic lines. Anyway, I cleaned the cylinder up internally by honing it out very little. Now I have re-sealed the cylinders and I have one that is constanlty bypassing. I can't figure out how or why. All seals have been replaced twice, still bypassing internally. I thought maybe it was one of the detent balls in the piston assembly, but all seem to be seating well. Anybody had a problem like this before? Wondering if I should just go ahead and bite the bullet on a new one or should I replace the piston assembly and sleeve. I think there is a kit out there for that?

 

[Laddies]

Re: Trim Cylinder Internal Leak

Usually a internal leak is either the ck valves on the plunger or the o ring in the front of the cyl that seals the spacer that holds the tube that the ram runs in.

 

[kwoolard]

Re: Trim Cylinder Internal Leak

I have replaced all of the seals, so I don't think that it could be a seal problem. Those ck valves are so small it is difficult to tell whether or not there are any imperfections in the ball or the balls seat. Is there just a piston assembly that I can buy that will have new detent balls?

 

[whywhyzed]

Re: Trim Cylinder Internal Leak

You honed them? I would look at that again. I would think the pitting of a seized or almost seized tube would be far more than the 1 or maybe 2 thou you could hone out. You can run the drive up and down a bunch and see if one cylinder gets warmer... The bypassing fluid might generate enough heat to feel it.