Hydraulic Cylinder Seal Sizes.

Titan17

Member

Equipment
L3901 TLB, Caroni RFM, Scag Wildcat ZTR, Piranha TB,York RE 96", MTL HD 48" grap
Jan 13, 2019
92
6
8
Uncasville, CT
Does anyone know where to find seal sizes for various hyd. cylinders on our tractors??. Naturally Kubota doesn't give much info for individual seals. You have to buy a complete kit which you don't need. ($90.-150. X 2).

I'd like to get the seals before disassembled so I can put together same day.
Otherwise take seal out, measure, order, wait, reinstall. 1 week at best.

Seals in question is swing cyl head on L39 BH.
 

D2Cat

Well-known member
Lifetime Member

Equipment
L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
13,816
5,557
113
40 miles south of Kansas City
Go to your nearby hydraulic repair shop. You may have to have is dis-assembled for them to itemize the parts, but they will be reasonably priced! It will be worth your trouble and wait.

Last Fall I needed kits for cylinders on a Bobcat. Bobcat wanted $40 for ea. cyl. I got them at the hyd. shop for $11 each.
 

sagor

Active member

Equipment
BX25, BX2750D, BX2760A, 5' back blade
Jan 9, 2017
285
58
28
Sudbury, ON, Canada
Does anyone know where to find seal sizes for various hyd. cylinders on our tractors??. Naturally Kubota doesn't give much info for individual seals. You have to buy a complete kit which you don't need. ($90.-150. X 2).

I'd like to get the seals before disassembled so I can put together same day.
Otherwise take seal out, measure, order, wait, reinstall. 1 week at best.

Seals in question is swing cyl head on L39 BH.
For that $90-$150 x2, you can probably get some hydraulic shop to rebuilt/repack your cylinder and pressure test it for you. Always worth asking around... If any shop says they are not interested, ask them if they know someone who might be, they always know who will do it...
 

lugbolt

Well-known member

Equipment
ZG127S-54
Oct 15, 2015
5,205
1,889
113
Mid, South, USA
There are 4 hydraulic shops near us.

The cheapest to rebuild one cylinder is about $175, includes pressure test and repaint if needed. And of those few that they've done, they were not excellent quality.

Rebuild them yourself. They're mostly easy. You'll need some hot water to soften up the plastic seals. Check the tubes for big scratches and check the rams for bend. If they have any visible bend, they will never seal up.
 

Titan17

Member

Equipment
L3901 TLB, Caroni RFM, Scag Wildcat ZTR, Piranha TB,York RE 96", MTL HD 48" grap
Jan 13, 2019
92
6
8
Uncasville, CT
I was hoping to get info on sizes before I disassembled; I could reassemble immediately. Closest hyd. shop is 1/2 hr away, and a little on the $$ side for parts. I'll bring the seal and match up.
I usually order from Motion Industries or BDI. Mail delivery is always cheaper than gas and drive time.
It's a 40mm rod X 70mm cyl bore (in case anyone knows off hand) cyl head sizes are standard. I'm going to guess seal is a polyurethane u-cup.
I'm not doing the piston just the head so as to fix leak.
Appreciate the advice from everyone. I'll post the size when I do the job in few weeks.
Love these Kubota's but they ROB us on parts!! Maybe because they don't break often.
 
Last edited:

motionclone

Well-known member
Lifetime Member

Equipment
L345DT with Lp mower, forks and grapple thumb, Bobcat 337 Midi Ex
May 4, 2018
1,398
996
113
Maine
I was hoping to get info on sizes before I disassembled; I could reassemble immediately. Closest hyd. shop is 1/2 hr away, and a little on the $$ side for parts. I'll bring the seal and match up.
I usually order from Motion Industries or BDI. Mail delivery is always cheaper than gas and drive time.
It's a 40mm rod X 70mm cyl bore (in case anyone knows off hand) cyl head sizes are standard. I'm going to guess seal is a polyurethane u-cup.
I'm not doing the piston just the head so as to fix leak.
Appreciate the advice from everyone. I'll post the size when I do the job in few weeks.
Love these Kubota's but they ROB us on parts!! Maybe because they don't break often.
Go to kubota parts store and measure whats in their bag of parts then go home and get online to match the seal size. You already know a couple parameters like rod diameter and cup type.

I recently purchased some seals from Oring store and they work great so far and low cost.

Im no pro, I just resealed a cylinder myself