DPS-A trim cylinder rebuild needed?

[saaristo]

While preparing things for the outdrive removal and painting I discovered that trim cylinder is leaking. Not really leaking like drippingf or anything but "sweating" if you know what I mean. IS that something that is in their nature or should they be completely dry outside?
I saw the cylinder ends were corroded already earlier, so they needed to be painted anyway, but now noticed also leaking. So I cleaned everything with a cloth and cleaner and seems to be the sweating comes from between the seal but also between the brass fitting and cylinder outer wall (3 o'clock position on the picture). It could be that it's the rubber seal between the brass and cylinder wall that's leaking but it might be that the corrosion has crawled deep between the two. If that's the case...bye-bye cylinder, right?
So what's the right course here to take - disconnet and empty the cylinders from oil, open the cylinders and see if the inner wall between the brass fitting has corrosion. If that's not the case then new seals for the brass fitting. But how do you refurbish the cylinder ends? Just paint them and leave them ugly but at least the corrosion won't get any further?
Any suggestions on how to proceed with this?

 

[alldodge]

I would rebuild it, and here is a good thread on how to
https://forums.iboats.com/threads/dps-a-trim-cylinder-rebuild.643967/

 

[saaristo]

I would rebuild it, and here is a good thread on how to
https://forums.iboats.com/threads/dps-a-trim-cylinder-rebuild.643967/

Thanks for the tip, that's a good start.
One thing that I can't find from any of the manuals is how to drain the fluid from trim cylinders and how to fill the system again? Or could it be possible to pry the metal cap retaining ring and drain the cylinder with pulling the rod out?

 

[alldodge]

The trim is self bleeding. Just fill and raise/lower a few times and all good

The center is held in place by a circlip

 

[Scott Danforth]

yep, the gland is held in with an internal snap ring or jesus clip.

 

[saaristo]

Ok, a plan is starting to develop, thank you guys. However, how do you get the old oil out? I would imagine if you just unscrew the small diameter hoses from cylinder the "vacuum" won't let the oil to drip out?

 

[Bondo]

Ok, a plan is starting to develop, thank you guys. However, how do you get the old oil out? I would imagine if you just unscrew the small diameter hoses from cylinder the "vacuum" won't let the oil to drip out?

Ayuh,..... Pull the ram off the drive, hold over a catch can, 'n manually pump it a time or two,.....
It'll then be nearly empty of oil,....

Fillin' is done by puttin' things back together, 'n runnin' it full up, 'n down a few times,....

 

[saaristo]

Thank you all for input. I'm wondering why the workshop manual asks to remove the outdrive before taking off the trim cylinders. Doesn't say why or anything, just the very first clause is you should remove the outdrive??

 

[alldodge]

The manifold is behind the drive. Takes very little to remove drive and get it out of your way