OK, I am rebuilding the bottom end of my b230. Kind of. I had open heart surgery about a month and a half ago, so I can't lift more than twenty pounds. Because of this, I decided not to drop the tranny and change/ grind the crankshaft. Instead I will collect parts, so when I'm better, I can swap them out. The new bearings will be at the loose end of spec (.050 clearance), but OK for a few thousand miles until I can swap out that old crank. The reason I am changing the bearings is because the exhuast manifold had a lot of soot in it, and I am putting a rebuilt head on it (sticking valve), and didn't want to ruin it prematurly with excessive blow-by. There for the rings had to go. And if I'm taking the pistons out, might as well do the con rod bearings, etc. etc.
Anyway, when I took the pistons out, the rod numbers are facing toward the wrong side of the engine (should be facing the oil filter), but the piston arrow is facing the right way (front of engine). The main bearings I took out were stamped 8/96, and the rod bearings were stamped 6/99, so someone put all new bearings in it recently. The rod bearings looked fine, but the main bearings were pretty torn up, although not that worn. My machine shop guy said it was probably from lots of dry starts. The crankshaft, even though the bearings were toast, is shiny and nice looking?!? The front main bearing and the middle main bearing were warped so they clung to the crankshaft like glue, and they don't fit into the holders anymore..... hmmmmmmm... the rods appear to be slightly out of balance (about 9%), although I am using a crappy food scale. Would this have toasted the main bearings? My machine shop said that was OK as well, as long as its not a performance engine - 10% is acceptable.
So, with that info, should I switch the rods around so the numbers point the right way (could the main bearing abuse have been from the rods being flipped?), or should I leave it. OR should I wait until I drop the new crank in, and do it then. I have torqued the rod bearings down once, which is the main thing that makes me leary of flipping the rods. I'm leaning toward waiting and doing it when I install the new crank, but???
Anybody have advice? I know this ain't exactly the right way to do things, but I feel alright about it as long as I can get the new crank in soon, with all new bearings of course. Waste of money, yes, but that's the way the cookie crumbled...