mercruiser 7.4l mpi crank position sensor

[cnotecherry]

I dont know if anyone will still read this but I cant seem to start a knew forum so heres my newest problem I just built a?marine?454?everthing was new except block (bored .030 over) and crankshaft std with a polish balanced and assembled by a very reputable engine shop they built me a short block and I did the rest. engine ran great for adout 10 hrs then my oil pressure dropped to almost zero opend the?oil filter?to find brass shaving, tore down the engine to find 2, 3, 4 main bearings spun and 1, 5 mains down to brass the?rod bearings?are fine except a few scars from the?main bearing?shavings cam bearings also fine except for scars from?main bearing?shavings to me this seems like a 100% assembly problem either not enough clearance on the main bearings, out of balance or bad polish ether way I feel there is nothing I could have done to prevent this as I was given an?assembled short block I?would like your opinions on this I am going to bring the engine back to the engine shop tomorrow

 

[alldodge]

I dont know if anyone will still read this but I cant seem to start a knew forum so heres my newest problem I just built a*marine*454*everthing was new except block (bored .030 over) and crankshaft std with a polish balanced and assembled by a very reputable engine shop they built me a short block and I did the rest. engine ran great for adout 10 hrs then my oil pressure dropped to almost zero opend the*oil filter*to find brass shaving, tore down the engine to find 2, 3, 4 main bearings spun and 1, 5 mains down to brass the*rod bearings*are fine except a few scars from the*main bearing*shavings cam bearings also fine except for scars from*main bearing*shavings to me this seems like a 100% assembly problem either not enough clearance on the main bearings, out of balance or bad polish ether way I feel there is nothing I could have done to prevent this as I was given an*assembled short block I*would like your opinions on this I am going to bring the engine back to the engine shop tomorrow

Agree, you had the machine shop build you a short block and 10 hours later the bearings are shot. So by the machine shop doing all the work and the bearings are gone they failed to do something, such as check clearance with plastic guage