I have a B7200d and replaced the dynamo (P/N- 15531-64013). All is working great. I disassembled the old Dynamo – P/N- 15531-64013. The housing had caked on dirt on the housing, The copper wiring looks good. Bearings all feel good. How can I test the winding to see if the winding is good. With the Dynamo off the tractor. Using a multimeter, what should the ohms be? Thanks