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Gland seal leak - first time rebuild questions and tips

B

bpp

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Joined
Mar 15, 2020
Messages
10
Location
Northeastern USA
My Bobcat 334 developed a leak on the boom cylinder between the gland and rod. I've never rebuilt a cylinder before and this is a home owner machine (with a home owner budget). I was hoping someone could tell me where I'm wrong and what else I should consider.

I got the thing apart, cleaned, and now I'm inspecting everything:
  • The rod/chrome looks good to my eye, nothing obvious that my fingers can detect for imperfections. Should I still give this a polish? If so, with what (maybe steel wool?)
  • The piston has some obvious rough areas. Is it OK to take these down with a file and sandpaper?
  • I can see/feel an obvious scratch in the gland where the seal goes. Is it a goner or can that be lightly sanded? I'm not sure if this was the failure or if I did this during removal.
  • I heard a bent rod could contribute to leak here. Is it worth having a shop check the rod if I have no reason to suspect it's bent?
  • Since the gland is aluminum, what should I put on the threads before reassembling?
ACtC-3fW7jRHk359Qa4iobdXVhrtsEoh4B_bPxRDWCSfUtgFrlpxlCMuTXNSQu8ClZgxNRBjDiznRw_nqaB9Gl2SweHXve6CMOm2ag08wXoyF9d1ueqzMWpFqQ51cow-l_MQ5BLTGEJ9MpMTD6GKE5jvEwV9=w1094-h1458-no
 
Coaldust

Coaldust

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Check the rod with a straight edge, if you have concerns.

320 grit, sanding roll. Wrap it around in a loop, radial. Not lengthwise. Go light. That makes a good finish for the new seals.
 
willie59

willie59

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I've seen glands in way worse shape than that, that actually looks pretty good. I wager it was just time for some new seals and you're good to go.
 
B

bpp

Member
Joined
Mar 15, 2020
Messages
10
Location
Northeastern USA
Thanks guys - I didn't post a picture of the piston but that has some rough edges on its outside diameter. I actually could not remove the piston from the cylinder when it was fully retracted, I had to push it out most of the way with the power of the machine before finishing it by hand. Is it common to have some wear there? I plan on sanding it too.
 
B

bpp

Member
Joined
Mar 15, 2020
Messages
10
Location
Northeastern USA
Thanks. Any thoughts on cleaning up the aluminum pieces that have obvious surface scratches? Is that commonly done?

I can't tell if that will cause more harm than good...my gut says any scratch smoothed out is better than left as is.
 
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