SKU SK-BC331-ARM-A
Bobcat 331 Arm Cylinder Seal Kit — S/N 232511001 & Above
Complete seal kit for the 2.5 in bore arm cylinder on the earlier 331, and for the boom swing cylinder, which shares the same bore and rod. Polyurethane rod and piston seals, bronze-filled PTFE wear rings, nitrile O-rings.
What's in this kit
Every seal in the kit, with its material and size.
| # | Qty | Part | Material | ID | OD / cross-section | Height | Shore A |
|---|---|---|---|---|---|---|---|
| 1 | 1 | Rod sealRS-1500-2000-313 · polypak | Polyurethane | 1.5" (38.1 mm) | 2" (50.8 mm) | 0.313" (7.95 mm) | 90 |
| 2 | 1 | Buffer sealBS-1500-2000-250 · buffer | PTFE / NBR | 1.5" (38.1 mm) | 2" (50.8 mm) | 0.25" (6.35 mm) | — |
| 3 | 1 | WiperWP-1500-1875-250 · dust wiper | Polyurethane | 1.5" (38.1 mm) | 1.875" (47.63 mm) | 0.25" (6.35 mm) | 90 |
| 4 | 1 | Rod bushingRB-1500-1625-375 · guide band | Bronze-filled PTFE | 1.5" (38.1 mm) | 1.625" (41.27 mm) | 0.375" (9.53 mm) | — |
| 5 | 1 | Piston sealPS-1750-2500-375 · t-seal | Polyurethane | 1.75" (44.45 mm) | 2.5" (63.5 mm) | 0.375" (9.53 mm) | 90 |
| 6 | 1 | O-ringOR-1750-139 · energizer | Nitrile (NBR) | 1.75" (44.45 mm) | 0.139" (3.53 mm) | — | 70 |
| 7 | 2 | Wear ringWR-2250-2500-500 · guide band | Bronze-filled PTFE | 2.25" (57.15 mm) | 2.5" (63.5 mm) | 0.5" (12.7 mm) | — |
| 8 | 1 | O-ringOR-2625-139 · gland seal | Nitrile (NBR) | 2.625" (66.67 mm) | 0.139" (3.53 mm) | — | 90 |
| 9 | 2 | Backup ringBU-2625-2900-50 · backup | Nylon | 2.625" (66.67 mm) | 2.9" (73.66 mm) | 0.05" (1.27 mm) | — |
Cylinders this kit services
Bobcat 331 Arm Cylinder (S/N 232511001 & Above)
- OEM no.
- 6804604
- Bore
- 2.5" (63.5 mm)
- Rod
- 1.5" (38.1 mm)
- Stroke
- 22.5" (571.5 mm)
- Closed
- 35.4" (899.16 mm)
- Gland
- threaded external
- Port
- SAE ORB #6
- Rod eye
- spherical bearing
Bobcat 331 Boom Swing Cylinder
- OEM no.
- 6805096
- Bore
- 2.5" (63.5 mm)
- Rod
- 1.5" (38.1 mm)
- Stroke
- 14" (355.6 mm)
- Closed
- 25" (635 mm)
- Gland
- threaded external
- Port
- SAE ORB #6
- Rod eye
- clevis
What this fits
| Machine | Serial range | Position |
|---|---|---|
| Bobcat 331 · E / G Series | S/N 232511001 & Above | Arm / Dipper |
| Bobcat 331 · E / G Series | All serials | Swing |
Our kits are dimensional equivalents built from seals we buy in. They fit and replace the original. They are not OEM parts and carry no OEM branding.
Not finding it?
Not sure this is right?
Check it with a caliper before you buy — how to measure bore, rod and stroke covers the mistakes behind most wrong orders. Send us the numbers and a photo of the old seals and we’ll confirm the fit before you spend anything.
Request a kit