SKU SK-CAT3035-BKT
Caterpillar 303.5E Bucket Cylinder Seal Kit
completeFull service kitbolt on gland
65 mm bore, 40 mm rod bucket cylinder kit for the 303.5E and 303.5E CR.
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-M40-M52-M8 · polypak | Polyurethane | 40 mm (1.5748") | 52 mm (2.0472") | 8 mm (0.315") | 90 |
| 2 | 1 | Buffer sealBS-M40-M52-M6 · buffer | PTFE / NBR | 40 mm (1.5748") | 52 mm (2.0472") | 6 mm (0.2362") | — |
| 3 | 1 | WiperWP-M40-M50-M7 · dust wiper | Polyurethane | 40 mm (1.5748") | 50 mm (1.9685") | 7 mm (0.2756") | 90 |
| 4 | 1 | Rod bushingRB-M40-M44-M10 · guide band | Bronze-filled PTFE | 40 mm (1.5748") | 44 mm (1.7323") | 10 mm (0.3937") | — |
| 5 | 1 | Piston sealPS-M45-M65-M10 · t-seal | Polyurethane | 45 mm (1.7717") | 65 mm (2.5591") | 10 mm (0.3937") | 90 |
| 6 | 1 | O-ringOR-M45-M4 · energizer | Nitrile (NBR) | 45 mm (1.7717") | 3.53 mm (0.139") | — | 70 |
| 7 | 2 | Wear ringWR-M59-M65-M12 · guide band | Bronze-filled PTFE | 59 mm (2.3228") | 65 mm (2.5591") | 12 mm (0.4724") | — |
| 8 | 1 | O-ringOR-M68-M4 · gland seal | Nitrile (NBR) | 68 mm (2.6772") | 3.53 mm (0.139") | — | 90 |
| 9 | 2 | Backup ringBU-M68-M75-M2 · backup | Nylon | 68 mm (2.6772") | 75 mm (2.9528") | 1.5 mm (0.0591") | — |
Cylinders this kit services
Caterpillar 303.5E Bucket Cylinder
- OEM no.
- 285-1661
- Bore
- 65 mm (2.5591")
- Rod
- 40 mm (1.5748")
- Stroke
- 480 mm (18.8976")
- Gland
- bolt on
- Port
- SAE ORB #8
- Rod eye
- spherical bearing
What this fits
| Machine | Serial range | Position |
|---|---|---|
| Caterpillar 303.5E · E Series CR | All serials | Bucket / Curl |
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