Bearing analysis please!
Posted: Sun Sep 06, 2015 11:03 pm
Pulled apart a 7A of unknown mileage, engine sat for a long time and a little moisture got in one of the bores, cleaned it up with a scotchbrite pad and now can't feel any roughness in the bore, just some discoloring.
Main caps have interesting wear pattern, front looks brand new, rear most cap looks like it has substantial wear on one side, the farther back the bearing, the more wear it has, rod bearings look ok from what I can tell.
Inside of engine is pretty clean, head is really clean, either the owner changed the oil alot, or it has relatively few miles....
So I was gonna do a poor mans rebuild: have a machine shop hot tank and clean, measure and inspect everything, then reassemble with new rod bolts and possibly 034 coated rod bearings (do I need new mains?), I also have ARP head studs, head would be cleaned up with most likely a valve job. I was going to keep the original rings unless the shop finds something wrong.
Here's the basic intent of this engine (turbo build, E85, 300 crank hp): http://www.theprojectpad.com/viewtopic.php?f=10&t=1719






Main caps have interesting wear pattern, front looks brand new, rear most cap looks like it has substantial wear on one side, the farther back the bearing, the more wear it has, rod bearings look ok from what I can tell.
Inside of engine is pretty clean, head is really clean, either the owner changed the oil alot, or it has relatively few miles....
So I was gonna do a poor mans rebuild: have a machine shop hot tank and clean, measure and inspect everything, then reassemble with new rod bolts and possibly 034 coated rod bearings (do I need new mains?), I also have ARP head studs, head would be cleaned up with most likely a valve job. I was going to keep the original rings unless the shop finds something wrong.
Here's the basic intent of this engine (turbo build, E85, 300 crank hp): http://www.theprojectpad.com/viewtopic.php?f=10&t=1719





