Lehman 120 Jabsco impeller
I normally replace my Jabsco pump impeller of the Lehman 120 engine every two years. I have always used the Jabsco impeller 1210-0001 made in the USA. This year I replaced it with the same impeller and noticed that now ITT-Jabsco was bought out by Xylem, and that the same impeller now is made in Italy. Not caring where it is manufactured, I installed it the usual way. To my surprise it did not pump any water and the engine overheated right away. I pulled over in an emergency and scratched my head. After some consideration I decided to put back the old impeller, and suddenly the pump works normally. I contacted Xylem and told them my story, and they apologized and sent me two new Jabsco impellers free of charge. I opened one and noticed it was identical to the one that failed. I installed it and it behaved the exact same way: no water output. Back to the old impeller and everything was fine again.
I hold the old and the new impellers side by side and see that they have the same dimensions, except perhaps the new Xylem impeller is softer, while the two year old made in US impeller was stiffer, and has a faster bounce back when you bend the vanes back with your finger. Has anybody experienced the same problem? Is Xylem using a wrong neoprene formulation? Upon American Diesel's advice, I am switching over to Johnson's impeller. We'll see how the Johnson impeller fares after I have a chance to install it, but I am curious to hear others' experience.