Metal fillings in new rebuilt 69 350

[BLT gmc]

Well as you can imagine last night was not good. Original to truck 69 350 had a spun rod bearing and a thrust bearing failure at some time. Reputable local machine shop did all the machine work and assembled the long block. 30 over bore, stock date correct heads, roller rockers, Flat tappet hyrdualic cam.

I installed the motor and fired it up. No obvious problems. Drained the oil and changed filter. No obvious problems. Break in driving now and I notice an increasing noise valve train or lifter type. Last night I dropped the oil and filter. Lots of fine ground metal in top of filter and lots clumped to the magnetic drain. What are your thoughts? Where to start? Valve covers are off. Intake is off. No obvious source of metal yet. Ideas? Bruce