If it is a small crack in the wood, a good quality filler putty that matches the color will work fine. If the blocks have separated at the seam/joint, you have to remove the butcher block, glue it back together and clamp it until the glue cures, then put it back on the counter. Finish sanding is required with either method.
Fix the tally in the counter
You can fix a zipper that has split open by clamping it with a pliers
How do you fix a split earlobe?
Longitudinal Split Tear on Shoulder
You can fix it with glue
It would depend on what is wrong with it.
You can use WINE.
You glue it with good wood adhesive.
You replace the engine.
Need to know what is wrong with it before we can help Joe fix it.
Take it to a shop. Cheap fix or call and ask if they have a deep socket!
does nanotechnology ( head gasket and block repair) fix blowen head gasket