Hey to all you awesome engine building guys out there . I just took apart a 78,000mile 73 BBC 454 and was wondering what you think of these bearing wear marks? The motor has no oil crud of any sort in it and is spotlessly clean .The surfaces are DEAD smooth across the bearing and laterally, it's all just microscopic . The crank oil supply hole has virtually no chamfer to it , could this be wiping the oil away from the bearing or leaving this pattern ? .....What would be in your expert opinions the best way to chamfer this oil hole , im taking the crank out and will clean it 100% afterwards ....i've researched this on the net and have found a 100 different conflicting ways to do it and by how much !! Thanks in advance for any info / suggestions ! J
It's been awhile so I cannot remember, but have you checked other cranks to see if they have a chamfer from the factory? I do recall seeing cranks with chamfers, but not exactly what they looked.
I would suspect those marks might have been from a dry start, day one. Possibly even from rotating the crank with no lube during assembly or before initial start. If the scoring is microscopic, it could not have been starving for oil for any significant amount of time...
We used to lube every bearing with a white grease as it was assembled. Lubriplate No. 105 if memory serves me. Should have stuck around until it was flushed out by engine oil after start-up.
