I pulled apart a 010 SBC block and all the rod bearings look like this.I have never seen anything like this before.The bearings are 20 under but the engine was holding 40 pounds of oil pressure with the bearings like this.Any idea what would cause this??

 

Dirt and oil starvation.

That particular picture looks like oil starvation.

 

But why only where in one spot and not all the way around the bearing??

 

Hot spots...

 

though i've only built 2 motors, I'd say the tolerances weren't correct. Did you build the motor? Get it from someone? Build it yourself? The only reason i can think of is oil starvation also. But I'm thinking because the crank was turned, but wasnt turned the same all over.

 

Looks like dirt behind the bearings (that's what caused the funky spots where the bearing was pressed up against the crank); and dirt in the oil.

The first thing happened while the engine was being built. Somebody simply wasn't clean enough about how they did it.

Check about 1" below the main cap register surface of the block, where the rear main cap goes, on the side toward the oil filter. There's a vertical passage there, that goes all the way from the main cap surface, to the intake sealing surface where the oil pressure sender screws in. Is there a freeze plug there, about 1" or so below that surface? Lack of that freeze plug will allow the oil to go directly from the pump to the bearings, without passing through the filter to get there.

 

Im glad it's just that!!I was thinking the rods might've been screwed and outa shape somehow.I'll throw some bearings in it and see what poundage it holds because the crank looks fine--no nicks or grooves.The engine will basicly just be a temporary to move the car around a bit but will eventually be built into a 327.Thanks

 

So, is that freeze plug in there where it belongs?

Your new bearings may not last any longer than these, without it.

 

Yeah it was there.Maybe the idiot before me never changed the filter or was just dirty putting it together.I put bearings back in it and started it and still just holding 40 pounds.Shut it down a while and started it back and it started popping through the carb.Moved the timing around till it stopped but it seems to have no throttle response.I thought timing had jumped and pulled the front cover and nope marks lined up perfect and the gearset and chain looked new with no visable wear.Checked distributer setting and it was 180 out.Done the thumb trick to make sure.Flipped distributer around and now it still wont restart and cranked slow real slow so pulled out the timing light and got a base timing to see if it would start and still no go and still cranked slow no matter where i put the distributer.And when you crank it every revolution you hear a bleed off through the carb like a exhaust valve isnt opening or a intake valve is screwed.I'm going to pull the valve covers tommorow and see if all rrockers are moving and reset the lash and see if that helps.

How far should i turn them down after zero lash for a preset and how should they be set while running IF it starts back.I'd hate to pull the engine completely apart now as funds are a lil low for a full build.While im thinking about it what would be a good set of budget heads for a street 327 or 350??And has anyone used one of the new lunati voodoo cams??Thanks

 

Anyone??

 

Spark plug wires on wrong? Check firing order and retime with light. Could be a valve too tight if not that. With engine idling, loosen each rocker until you hear a click that keeps on clicking, tighten until it quits then 1/2 turn more.