LT1 swap in 83 Cutlass too many rebuilds!!!!!

[Major_Bill]

Ok guys I knew the first time i had to rebuild my Lt1 in my cutlass whats was wrong I tack welded my oil screen to pump instead of brazing it . I know stupid mistaKE AND i SPUN a couple of bearing . I had my crank turn and rods resized by local machine shop I even order a new melling oil pump that high volume thats a press and bolt in screen The local machine shop went ahead and put the short block together for me since this wa my second time seeing them. I put the Lt1 back in set the VALVES AND DROVE IT ABOUT 40 MILES AND GUESS WHAT OIL PRESSURE DROPED FROM 60 TO 40 I WAS ONLY 7 MILES FROM THE HOUSE AND THE DREDED KNOCK STARTED. I CALLED THE LOCAL MACHINE SHOP HE CAME BY TO LISTEN TO IT. IT JUST SO CRAZY CAUSE THE OIL PRESSURE WAS GOOD AND THE KNOCK CAME AND WENT. I TOOK IT APART OIL SCREEN STILL IN PLACE. BEARING 7 AND 8 BOTH WERE WORE SIGNIFICANTLY. WHAT CAN CAUSE THIS? WHAT HAPPENED THIS TIME? IS IT POSSIBLE TO TURN A CRANK TOO MANY TIMES BEFORE IT BECOMES WEAK? THE LAST TIME WE TURNED THE CRANK IT WAS 30/40

 

[Major_Bill]

I really thought some vets were going to chime in on this because I'm really puzzled. The local machine shop theory is the oil filter I used a ac delco 1218 filter . He told me i should have used a wix racing filter with the high volume oil pump What do you think?

 

[DRIVEN]

I think I'd shop around for another machine shop. High volume oil pumps are a crutch to compensate for sloppy clearances. There should be nothing wrong with a OEM filter. I don't have an answer as to why 7&8 went so soon. Did you do anything to prime the engine before firing it? A crankshaft that's been turned .030/.040 is pretty undersized but shouldn't be measurably weaker or cause this problem. I think you either had debris in the engine or there wasn't proper priming before initial start-up.

 

[Major_Bill]

Yes I primed it and oil seemed to flow well I adjusted my valves and oil clearly shot over the hood of my other cars . I'm just baffled