Technical Cleaning vent tube on a Turbo 250/350, HELP!

What kind of cable is it, OEM black plastic housing, or is it a Lokar?

You could see about putting a normal old dipstick and tube on it, see if that helps.

 

Stock cable I think. Came with the transmission. I had an idea today, I cut the end off and melted the tip closed. I figure, one of two things will happen, one the trans wills top leaking and all will be right with the world, or two it'll blow up.

So far no leaks and it still shifts fine on my short little jaunts.

 

That should get you by for now. The 350 will work without the detent cable, but it won't work completely right, since there's no line pressure boost at full throttle upshifts. If the trans is in good shape, it should last for years like that.