Well the debate begins anew (for me), Lycoming SB 505B...
The (certified) Machine shop reviewed the O-320 crankshaft that I sent, and cannot yellow tag per the SB. They pulled the front plug, machined the paint off, and stated that there is pitting beyond acceptance criteria.
In discussions with them
-I inquired as to whether they felt it was suitable for Experimental use. They replied that they thought that the SB was essentially over-cautious, and that it would be suitable for flight where certification to the SB, was not required
-They advised against machining the I.D., stating that even if machined, it would not clean up the pits. There would be .009" diametral available, to the max allowable O.D of 1.910", or .0045" radial that could be removed.
-They advised against repainting, stating that they felt the paint could be detrimental to further corrosion, or at lease didn't mitigate further corrosion, once evident.
So the question now becomes, what to do. The options seem to be:
1. Use the crankshaft as-is. Pull the Lycoming I.D. plate and build an engine with an uncertified crank. There are many opinions on this, I've read what I could find on this website, I'm open to a new discussion.
-The engine I have does not have logbooks, but the paperwork I did find showed 11K hours TT in 2001. It was an engine from a school plane, I don't know how much or if it flew after that before the builder purchased it. No bill of sale. Cylinders look OK, I think they'll be able to be overhauled. Cases look OK at Disassy, and I have the accessories. It came with the project I bought from another builder's estate, there was no more info about it,,,
2. Find a used yellow tag crank. Hard to do, very popular, what everyone else needs too. Every crank has a past.....
3. Buy a new crank. Expensive, and would you put one in an eleven thousand hour case?
4. Find another core engine. and hope its crank is certifiable....
5. Buy a new Lycoming engine from Van's. Money as always, is a factor.. I would assuredly have to check with the internal finance dept.
6. Find a used/mid-time engine deal.
The machine shop will finish NDT and dimensional inspections, polish the journals (all were serviceable at oem new dia's.), re-plug the front and return with inspection paperwork only. Cost was reasonable.
I'm evaluating what to do next.