Roper Pump D11-305 Gearcase Gasket for N41-3 Gear Reducers
The Roper D11-305 is the gearcase gasket for the N41-3 built-on gear reducer, the larger of the two reducer families and the one fitted to the 35, 48 and 58 pump frames. It seals the main joint where the gearcase halves come together, which is the longest sealing path in the whole reducer and the one that sees the most flexing as torque is applied and released through the day.
Because the reducer on a gear pump hangs off the pump head rather than sitting on its own base, the gearcase joint carries a share of the driveline load as well as holding oil. That is why a gearcase gasket that has been reused, or pinched during assembly, tends to show up first as a thin film of oil creeping down the pump body rather than as an obvious drip. Fit a new one whenever the case is split, seat it dry on clean faces, and pull the case bolts down evenly in stages so the joint closes square instead of hinging shut from one corner.
Key Features
- Genuine Roper Pump Company gearcase gasket, part number D11-305
- Cut to the N41-3 gearcase profile with bolt holes and oil passages already located
- Seals the full gearcase parting line against oil leakage
- Keeps the case halves correctly spaced so the gear mesh stays true
- Single use item renewed whenever the gearcase is split
Applications
- N41-3 built-on gear reducers for the 35, 48 and 58 pump frames
- Gear reduced pump packages running from standard speed motors
- Heavy and viscous liquid transfer that calls for a slow turning pump
- Asphalt, molasses, resin and heavy oil handling
- Planned reducer overhaul and oil leak repair
Specifications
- Brand: Roper Pump Company
- Part Number: D11-305
- Part Type: Gearcase gasket
- Fits: N41-3 gear reducers
- Function: Gearcase parting line seal
- Assembly: Built-on reducer mounted directly to the pump head
- Condition: New
Frequently Asked Questions
Q: Can I split the gearcase without draining the oil first?
Drain it. Oil left in the case runs across the sealing faces as soon as the joint opens, and a face that has been wetted is far harder to get properly clean for the new gasket.
Q: Do I need to reset any shims when the case goes back together?
Follow the shim arrangement you found on disassembly and keep the packs with the bearing they came from. Swapping packs side to side changes the mesh pattern even though the parts all look identical.
Q: What causes a gearcase joint to weep soon after a rebuild?
Most often the case bolts were taken down in the wrong order, so the joint closed unevenly. Backing them off and pulling the case down again in stages with a new gasket usually cures it.
Q: Is the reducer oil the same as the pumped product?
No. The reducer runs on its own charge of gear oil and is sealed away from the pumped stream. If you find product in the reducer, a shaft seal has failed and needs attention before the unit goes back in service.
Not sure this is the right part? Send us a Picture of the pump plate on your pump and the CLR Marine team will confirm the correct gearcase gasket before you order.
CLRMarine
