Just finished a complete overhaul on a 261 its got 45 lbs oil pressure but developed a knock soon after cam break-in. It was magnafluxed, bored .080, reconditioned rods with ARP bolts, Clevite bearings,.010/.010 crank, balanced, block decked .030, 848 head milled .050, new milling oil pump, new valves, seats springs and keepers, Patrick's solid cam, Clifford water heated 4 barrel maniford with 500 cfm edlebrock, fenton headers, electric fan,PCV system, full flow spin on filter, custom power steering pump bracket and lots of chrome.
I changed the break-in oil yesterday and found shinny metal flakes in the filter and a small amount of residue on the magnetic drain plug. The engine was assembled with edlebrock assembly lube and the oil pump was primed prior to start-up. The engine has about 100 miles on it.
The knock gets worse as the engine heats and the oil pressure drops to about 25 lbs. The knock does not change as plugs are individually grounded, so I assume it is a main bearing or cam bearing problem. Idle vacuum is a steady 20". Bearings were set up at .003 by the crank grinder, I wanted .0015-.002 but settled for what they gave me. I advanced the cam timing 4 degrees. I'm pulling the engine this weekend. Any ideas what went wrong inside? Do you think I should totally disassemble and clean the engine if I find an isolated bearing failure?
