Oil leakage: pump or main bearings?

Dear Sirs.
I have a MB10A engine that is losing oil prime in pump. I already installed the oil pipe with one way valve, but over long period it still loses prime. I live in the United States and want to know the price in U.S Dollars for new oil pump gear and housing. I also installed new gears two years ago, but maybe the housing is worn.


Hello, Regarding your MB10A engine:
We do not think that the reason you lose oil pressure it is due to failure connected to the oil pump, but rather that the engine’s main bearings are so worn out that oil leaks too much out when the engine is running. It is very seldom that the gears in the oil pump is so worn out, that they do not provide the proper oil pressure.

We also see that you have oilpipe with one way valve. In our opinion this confirms our supposition. We recommend that you to check the clearance in the main bearings first. If we are correct you may need 2 new main bearings somewhat undersize (std undersize is 0.5 m.m.) and we recommend that you grind the crankshaft down correspondingly, if the surface of the crankshaft main shafts are worn. Please check this and come back to us and let us know, and we give you our offer.