question about hydraulic cylinders

[HelpMe?]

I've got 2 leaky hydraulic cylinders. They're on a boat outdrive, but the principles seem the same and you guys seem like the most knowledgeable forum I could find for this question. I found 2 new "old stock" cylinders online for maybe $100 more than what it would cost me for the rebuild parts. Given that I'd need to dig up a gland nut wrench and fight them to disassemble, that seems like it makes more sense than trying to rebuild them. BUT, this boat manufacturer went out of business in the early 1990s, so it's possible they could be up to 25 years old. Any idea as to the he odds that the seals and o-rings might have gone bad over that time frame, even though they've never been used? Thanks for any insight you might be able to provide!

 

[Tazza]

It's really hard to say, they may last quite a while, but then again they may fail in a few weeks.
If they are new, they should be ok. Heat from operating seems to be the biggest killer of seals.
Fabricating a gland nut removal tool shouldn't be too hard, and then you would know the seals are new.....

 

[HelpMe?]

It's really hard to say, they may last quite a while, but then again they may fail in a few weeks.
If they are new, they should be ok. Heat from operating seems to be the biggest killer of seals.
Fabricating a gland nut removal tool shouldn't be too hard, and then you would know the seals are new.....

Thanks for your reply Tazza. I made an offer of $165 for two "new" cylinders which the seller accepted. That seemed like it's worth the risk that the seals will last a while instead of rebuiding mine. Unlike probably most readers of this forum, fabricating a gland nut wrench would be problematic for me as I don't have any metal working tools, not even drill bits.

 

[Tazza]

Thanks for your reply Tazza. I made an offer of $165 for two "new" cylinders which the seller accepted. That seemed like it's worth the risk that the seals will last a while instead of rebuiding mine. Unlike probably most readers of this forum, fabricating a gland nut wrench would be problematic for me as I don't have any metal working tools, not even drill bits.

That would make it a little more difficult, hopefully they will last, being new they really should.