I was taking the bearings out of my block the other day so I could take it to the machine shop to be bored and honed. When I was taking the main bearings out I slipped and have marked on of the surfaces on the block. It's quite small, but I really don't know if it will be safe to use again, the marks stand proud a little from the surface and catch on a fingernail.



Oh, hi from a newbie in the UK too. This site is a damn sight better than anything UK based.

 

just take a small die grinder like a dremel with a sanding wheel on it and very lightly sand the area you messed up.. but only the parts that are sticking up and DON'T try and blend it out with the rest of the bore.

 

Will that be safe though? The last thing I want to do is spin a bearing or similar on my newly built block.

 

since you are taking it to the machine shop......have them look at the marks. im sure they can lightly scuff the high spots down without any issues.

 

A line hone will take care of it. When putting it back together just make sure that you plastigauge your bearings to make sure your bearings provide the correct clearance.

 

Carefully file the high peaks off with a fine toothed needle file. Use a file with a gentle radius /curve across the width of the blade. Try not to file any of the 'flat' area, but a few slight scratches won't be an issue. Finish off by lightly rubbing with a very fine abrasive paper (1200 grit with the initial 'sharpness' worn off).