How do I tell if my valves are still in good shape? They are pretty black on the bottom, but so are the tops of my pistons. I know my rings were shot. Is this just normal deposits or do my valves need to be replaced? Also, is it ok to just clean them up with a wire brush drill bit?

 

It is normal to have some carbon buildup on the valves (there will typically be more buildup on the intake valves than on the exhaust valves). I used a wire brush and varsol to clean the valves and seats up when I rebuilt my heads. The deposits weren't that hard to remove.

Don't be overly concerned with the bottom of the valves (clean the worse stuff off as best as you can). What you are concerned with is the sealing surface of the valves and seats. Remove the valves from the head (if they're not off already) so that you can clean the sealing surfaces well, replace the valve stem seals while you have the valves out, then re-install the clean valves in the heads.

You can check the sealing surface of the valves using a marking paint made specifically for that. You open the valve, paint the sealing surface on just the valve (not the seat) with the paint, close the valve, re-open the valve, then check that you have complete coverage of paint around the whole perimeter of the valve seat, with no gaps. That will tell you whether or not you have to lap your valves and seats.