Oberdorfer 705.71 Check Valve – Buna-n Replacement Part
Check valves keep a pump primed between runs and stop flow reversing when it stops. The Oberdorfer 705.71, made in Buna-N (nitrile), is the factory part for that duty.
A valve that no longer seats gives itself away: the pump loses prime overnight, output falls off, or the system will not hold pressure when the pump stops. Debris on the seat and a hardened elastomer are the two usual causes.
Note the orientation on removal. A check valve fitted backwards blocks the flow entirely and the fault is easily missed.
Key Features
- Genuine Oberdorfer 705.71 valve component
- Manufactured in Buna-N (nitrile)
- Seats to hold prime or limit discharge pressure
- Material grade selected for the pumped fluid
- Direct replacement with no modification required
Applications
- Suction lines that must hold prime between runs
- Positive displacement pump relief arrangements
- Marine raw water and transfer installations
- Industrial circulation and dosing systems
- Overhaul of Oberdorfer pump assemblies
Specifications
- Brand: Oberdorfer
- Manufacturer: Ingersoll Rand
- Manufacturer Part Number: 705.71
- Part Type: Check Valve
- Material: Buna-N (nitrile)
- Condition: New
Frequently Asked Questions
Q: Why does the pump lose prime overnight?
A check valve that is not seating is the usual reason, either from debris on the seat or from an elastomer that has hardened.
Q: Does orientation matter on fitting?
Very much on a check valve. Note which way it came out before it goes anywhere near the bench.
Q: Can a relief setting be adjusted?
Only where the design provides for it. Do not attempt to increase a relief setting to cure a flow problem elsewhere in the system.
Q: Which elastomer grade should I choose?
Match it to the fluid and its temperature rather than to what came out, since the original may itself have been a substitution.
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 check valve before you order.
CLRMarine
