Oberdorfer NL4000L

[eseerup]

Im looking to replace the rear seal on our Oberdorfer NL4000L pump that is on a Grimm 7" filter press. the seal blew out the back and leaks. When i contacted Oberdorfer they wanted me to buy the kit for $300 when i just need the $10 seal in the back. Does anyone know what size or where i could get just the seal to replace it?

[DrTimPerkins]

You could try

https://www.pumpsandpartsonline.com/...r-pumps/N4000L or

https://www.pumpvendor.com/Oberdorfer_Parts_List.html

[WMF]

Do you need the shaft seal or the thin paper like gasket that seals the two case halves? I think the shaft seal is just a packing like material that gets compressed by the gland nut the shaft goes through.
The case gasket if used could be cut out with a razor knife but should be the exact same thickness material so the clearance between gears and case stays the same.
If it comes down to spending some serious money consider going to an air pump or one of the newer electric powered diaphragm pumps.

[eseerup]

In that first link it's S3 and S15. We haven't taken it apart but it leaks out on the shaft.

You could try

https://www.pumpsandpartsonline.com/...r-pumps/N4000L or

https://www.pumpvendor.com/Oberdorfer_Parts_List.html

[WMF]

If you have not already done so you might try tightening the gland nut as that will compress the packing material around the shaft and might stop your leak.
I would rinse pump with hot water until pump is hot, remove the belt and gauge how easy the pump turns by hand and tighten the gland nut until it turns just slightly harder. It is normal to have to adjust the gland nut as the pump ages.